draft-ietf-manet-olsrv2-09.txt   draft-ietf-manet-olsrv2-10.txt 
Mobile Ad hoc Networking (MANET) T. Clausen Mobile Ad hoc Networking (MANET) T. Clausen
Internet-Draft LIX, Ecole Polytechnique Internet-Draft LIX, Ecole Polytechnique
Intended status: Standards Track C. Dearlove Intended status: Standards Track C. Dearlove
Expires: January 14, 2010 BAE Systems ATC Expires: March 29, 2010 BAE Systems ATC
P. Jacquet P. Jacquet
Project Hipercom, INRIA Project Hipercom, INRIA
The OLSRv2 Design Team The OLSRv2 Design Team
MANET Working Group MANET Working Group
July 13, 2009 September 25, 2009
The Optimized Link State Routing Protocol version 2 The Optimized Link State Routing Protocol version 2
draft-ietf-manet-olsrv2-09 draft-ietf-manet-olsrv2-10
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Abstract Abstract
This document describes version 2 of the Optimized Link State Routing This document describes version 2 of the Optimized Link State Routing
(OLSRv2) protocol for Mobile Ad hoc NETworks (MANETs). (OLSRv2) protocol for Mobile Ad hoc NETworks (MANETs).
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 5 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 5
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 6 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 6
3. Applicability Statement . . . . . . . . . . . . . . . . . . . 7 3. Applicability Statement . . . . . . . . . . . . . . . . . . . 8
4. Protocol Overview and Functioning . . . . . . . . . . . . . . 8 4. Protocol Overview and Functioning . . . . . . . . . . . . . . 9
4.1. Routers and Interfaces . . . . . . . . . . . . . . . . . . 10 4.1. Overview . . . . . . . . . . . . . . . . . . . . . . . . . 9
4.2. Information Base Overview . . . . . . . . . . . . . . . . 11 4.2. Routers and Interfaces . . . . . . . . . . . . . . . . . . 11
4.2.1. Local Information Base . . . . . . . . . . . . . . . . 11 4.3. Information Base Overview . . . . . . . . . . . . . . . . 12
4.2.2. Interface Information Bases . . . . . . . . . . . . . 11 4.3.1. Local Information Base . . . . . . . . . . . . . . . . 12
4.2.3. Neighbor Information Base . . . . . . . . . . . . . . 11 4.3.2. Interface Information Bases . . . . . . . . . . . . . 12
4.2.4. Topology Information Base . . . . . . . . . . . . . . 12 4.3.3. Neighbor Information Base . . . . . . . . . . . . . . 13
4.2.5. Processing and Forwarding Information Base . . . . . . 13 4.3.4. Topology Information Base . . . . . . . . . . . . . . 13
4.3. Signaling Overview . . . . . . . . . . . . . . . . . . . . 13 4.3.5. Received Message Information Base . . . . . . . . . . 14
5. Protocol Parameters and Constants . . . . . . . . . . . . . . 14 4.4. Signaling Overview . . . . . . . . . . . . . . . . . . . . 15
5.1. Protocol and Port Numbers . . . . . . . . . . . . . . . . 14 4.5. Routing Set . . . . . . . . . . . . . . . . . . . . . . . 16
5.2. Multicast Address . . . . . . . . . . . . . . . . . . . . 15 5. Protocol Parameters and Constants . . . . . . . . . . . . . . 16
5.3. Local History Times . . . . . . . . . . . . . . . . . . . 15 5.1. Protocol and Port Numbers . . . . . . . . . . . . . . . . 17
5.4. Message Intervals . . . . . . . . . . . . . . . . . . . . 15 5.2. Multicast Address . . . . . . . . . . . . . . . . . . . . 17
5.5. Advertised Information Validity Times . . . . . . . . . . 16 5.3. Local History Times . . . . . . . . . . . . . . . . . . . 17
5.6. Received Message Validity Times . . . . . . . . . . . . . 17 5.4. Message Intervals . . . . . . . . . . . . . . . . . . . . 18
5.7. Jitter . . . . . . . . . . . . . . . . . . . . . . . . . . 17 5.5. Advertised Information Validity Times . . . . . . . . . . 18
5.8. Hop Limit Parameter . . . . . . . . . . . . . . . . . . . 18 5.6. Received Message Validity Times . . . . . . . . . . . . . 19
5.9. Willingness . . . . . . . . . . . . . . . . . . . . . . . 18 5.7. Jitter . . . . . . . . . . . . . . . . . . . . . . . . . . 20
5.10. Parameter Change Constraints . . . . . . . . . . . . . . . 19 5.8. Hop Limit Parameter . . . . . . . . . . . . . . . . . . . 20
6. Information Bases . . . . . . . . . . . . . . . . . . . . . . 20 5.9. Willingness . . . . . . . . . . . . . . . . . . . . . . . 21
6.1. Local Information Base . . . . . . . . . . . . . . . . . . 21 5.10. Parameter Change Constraints . . . . . . . . . . . . . . . 21
6.1.1. Originator Set . . . . . . . . . . . . . . . . . . . . 21 6. Information Bases . . . . . . . . . . . . . . . . . . . . . . 22
6.1.2. Local Attached Network Set . . . . . . . . . . . . . . 21 6.1. Local Information Base . . . . . . . . . . . . . . . . . . 23
6.2. Neighbor Information Base . . . . . . . . . . . . . . . . 22 6.1.1. Originator Set . . . . . . . . . . . . . . . . . . . . 23
6.3. Topology Information Base . . . . . . . . . . . . . . . . 22 6.1.2. Local Attached Network Set . . . . . . . . . . . . . . 24
6.3.1. Advertised Neighbor Set . . . . . . . . . . . . . . . 22 6.2. Neighbor Information Base . . . . . . . . . . . . . . . . 24
6.3.2. Advertising Remote Router Set . . . . . . . . . . . . 23 6.3. Topology Information Base . . . . . . . . . . . . . . . . 25
6.3.3. Topology Set . . . . . . . . . . . . . . . . . . . . . 23 6.3.1. Advertising Remote Router Set . . . . . . . . . . . . 26
6.3.4. Attached Network Set . . . . . . . . . . . . . . . . . 24 6.3.2. Router Topology Set . . . . . . . . . . . . . . . . . 26
6.3.5. Routing Set . . . . . . . . . . . . . . . . . . . . . 25 6.3.3. Routable Address Topology Set . . . . . . . . . . . . 27
6.4. Processing and Forwarding Information Base . . . . . . . . 25 6.3.4. Attached Network Set . . . . . . . . . . . . . . . . . 27
6.4.1. Received Set . . . . . . . . . . . . . . . . . . . . . 25 6.3.5. Routing Set . . . . . . . . . . . . . . . . . . . . . 28
6.4.2. Processed Set . . . . . . . . . . . . . . . . . . . . 26 6.4. Received Message Information Base . . . . . . . . . . . . 28
6.4.3. Forwarded Set . . . . . . . . . . . . . . . . . . . . 26 6.4.1. Received Set . . . . . . . . . . . . . . . . . . . . . 29
6.4.4. Relay Set . . . . . . . . . . . . . . . . . . . . . . 27 6.4.2. Processed Set . . . . . . . . . . . . . . . . . . . . 29
7. Message Processing and Forwarding . . . . . . . . . . . . . . 27 6.4.3. Forwarded Set . . . . . . . . . . . . . . . . . . . . 30
7.1. Actions when Receiving a Message . . . . . . . . . . . . . 28 6.5. Corresponding Protocol Tuples . . . . . . . . . . . . . . 30
7.2. Message Considered for Processing . . . . . . . . . . . . 28 7. Message Processing and Forwarding . . . . . . . . . . . . . . 31
7.3. Message Considered for Forwarding . . . . . . . . . . . . 29 7.1. Actions when Receiving a Message . . . . . . . . . . . . . 32
8. Packets and Messages . . . . . . . . . . . . . . . . . . . . . 31 7.2. Message Considered for Processing . . . . . . . . . . . . 32
8.1. HELLO Messages . . . . . . . . . . . . . . . . . . . . . . 32 7.3. Message Considered for Forwarding . . . . . . . . . . . . 33
8.1.1. HELLO Message TLVs . . . . . . . . . . . . . . . . . . 32 8. Packets and Messages . . . . . . . . . . . . . . . . . . . . . 35
8.1.2. HELLO Message Address Block TLVs . . . . . . . . . . . 33 8.1. HELLO Messages . . . . . . . . . . . . . . . . . . . . . . 36
8.2. TC Messages . . . . . . . . . . . . . . . . . . . . . . . 33 8.1.1. HELLO Message TLVs . . . . . . . . . . . . . . . . . . 37
8.2.1. TC Message TLVs . . . . . . . . . . . . . . . . . . . 34 8.1.2. HELLO Message Address Block TLVs . . . . . . . . . . . 37
8.2.2. TC Message Address Block TLVs . . . . . . . . . . . . 34 8.2. TC Messages . . . . . . . . . . . . . . . . . . . . . . . 37
9. HELLO Message Generation . . . . . . . . . . . . . . . . . . . 35 8.2.1. TC Message TLVs . . . . . . . . . . . . . . . . . . . 39
9.1. HELLO Message: Transmission . . . . . . . . . . . . . . . 35 8.2.2. TC Message Address Block TLVs . . . . . . . . . . . . 39
10. HELLO Message Processing . . . . . . . . . . . . . . . . . . . 36 9. HELLO Message Generation . . . . . . . . . . . . . . . . . . . 40
10.1. Updating Willingness . . . . . . . . . . . . . . . . . . . 36 9.1. HELLO Message: Transmission . . . . . . . . . . . . . . . 41
10.2. Updating MPR Selectors . . . . . . . . . . . . . . . . . . 36 10. HELLO Message Processing . . . . . . . . . . . . . . . . . . . 41
10.3. Symmetric 1-Hop and 2-Hop Neighborhood Changes . . . . . . 37 10.1. Updating Willingness . . . . . . . . . . . . . . . . . . . 42
11. TC Message Generation . . . . . . . . . . . . . . . . . . . . 38 10.2. Updating MPR Selectors . . . . . . . . . . . . . . . . . . 42
11.1. TC Message: Transmission . . . . . . . . . . . . . . . . . 39 11. TC Message Generation . . . . . . . . . . . . . . . . . . . . 43
12. TC Message Processing . . . . . . . . . . . . . . . . . . . . 40 11.1. TC Message Transmission . . . . . . . . . . . . . . . . . 44
12.1. Invalid Message . . . . . . . . . . . . . . . . . . . . . 40 12. TC Message Processing . . . . . . . . . . . . . . . . . . . . 45
12.2. Initial TC Message Processing . . . . . . . . . . . . . . 41 12.1. Invalid Message . . . . . . . . . . . . . . . . . . . . . 45
12.3. Initial TC Message Processing . . . . . . . . . . . . . . 42 12.2. TC Message Processing Definitions . . . . . . . . . . . . 47
12.3.1. Populating the Advertising Remote Router Set . . . . . 42 12.3. Initial TC Message Processing . . . . . . . . . . . . . . 47
12.3.2. Populating the Topology Set . . . . . . . . . . . . . 43 12.3.1. Populating the Advertising Remote Router Set . . . . . 48
12.3.3. Populating the Attached Network Set . . . . . . . . . 43 12.3.2. Populating the Router Topology Set . . . . . . . . . . 48
12.4. Completing TC Message Processing . . . . . . . . . . . . . 44 12.3.3. Populating the Routable Address Topology Set . . . . . 49
12.4.1. Purging the Topology Set . . . . . . . . . . . . . . . 44 12.3.4. Populating the Attached Network Set . . . . . . . . . 49
12.4.2. Purging the Attached Network Set . . . . . . . . . . . 44 12.4. Completing TC Message Processing . . . . . . . . . . . . . 50
13. Information Base Changes . . . . . . . . . . . . . . . . . . . 45 12.4.1. Purging the Router Topology Set . . . . . . . . . . . 50
14. Selecting MPRs . . . . . . . . . . . . . . . . . . . . . . . . 46 12.4.2. Purging the Routable Address Topology Set . . . . . . 50
15. Populating Derived Sets . . . . . . . . . . . . . . . . . . . 48 12.4.3. Purging the Attached Network Set . . . . . . . . . . . 51
15.1. Populating the Relay Set . . . . . . . . . . . . . . . . . 48 13. Information Base Changes . . . . . . . . . . . . . . . . . . . 51
15.2. Populating the Advertised Neighbor Set . . . . . . . . . . 48 13.1. Originator Address Changes . . . . . . . . . . . . . . . . 51
16. Routing Set Calculation . . . . . . . . . . . . . . . . . . . 49 13.2. Neighbor State Changes . . . . . . . . . . . . . . . . . . 51
16.1. Network Topology Graph . . . . . . . . . . . . . . . . . . 49 13.3. Advertised Neighbor Changes . . . . . . . . . . . . . . . 52
16.2. Populating the Routing Set . . . . . . . . . . . . . . . . 50 13.4. Advertising Remote Router Tuple Expires . . . . . . . . . 52
16.3. Routing Set Updates . . . . . . . . . . . . . . . . . . . 51 13.5. Neighborhood Changes and MPR Updates . . . . . . . . . . . 53
17. Proposed Values for Parameters and Constants . . . . . . . . . 51 13.6. Routing Set Updates . . . . . . . . . . . . . . . . . . . 54
17.1. Local History Time Parameters . . . . . . . . . . . . . . 51 14. Selecting MPRs . . . . . . . . . . . . . . . . . . . . . . . . 54
17.2. Message Interval Parameters . . . . . . . . . . . . . . . 51 15. Routing Set Calculation . . . . . . . . . . . . . . . . . . . 56
17.3. Advertised Information Validity Time Parameters . . . . . 52 15.1. Network Topology Graph . . . . . . . . . . . . . . . . . . 56
17.4. Received Message Validity Time Parameters . . . . . . . . 52 15.2. Populating the Routing Set . . . . . . . . . . . . . . . . 58
17.5. Jitter Time Parameters . . . . . . . . . . . . . . . . . . 52 16. Proposed Values for Parameters and Constants . . . . . . . . . 59
17.6. Hop Limit Parameter . . . . . . . . . . . . . . . . . . . 52 16.1. Local History Time Parameters . . . . . . . . . . . . . . 59
17.7. Willingness Parameter and Constants . . . . . . . . . . . 52 16.2. Message Interval Parameters . . . . . . . . . . . . . . . 59
18. Sequence Numbers . . . . . . . . . . . . . . . . . . . . . . . 52 16.3. Advertised Information Validity Time Parameters . . . . . 59
19. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 53 16.4. Received Message Validity Time Parameters . . . . . . . . 60
19.1. Message Types . . . . . . . . . . . . . . . . . . . . . . 53 16.5. Jitter Time Parameters . . . . . . . . . . . . . . . . . . 60
19.2. Message TLV Types . . . . . . . . . . . . . . . . . . . . 53 16.6. Hop Limit Parameter . . . . . . . . . . . . . . . . . . . 60
19.3. Address Block TLV Types . . . . . . . . . . . . . . . . . 54 16.7. Willingness Parameter and Constants . . . . . . . . . . . 60
20. Security Considerations . . . . . . . . . . . . . . . . . . . 55 17. Sequence Numbers . . . . . . . . . . . . . . . . . . . . . . . 60
20.1. Confidentiality . . . . . . . . . . . . . . . . . . . . . 55 18. Extensions . . . . . . . . . . . . . . . . . . . . . . . . . . 61
20.2. Integrity . . . . . . . . . . . . . . . . . . . . . . . . 56 19. Security Considerations . . . . . . . . . . . . . . . . . . . 62
20.3. Interaction with External Routing Domains . . . . . . . . 57 19.1. Confidentiality . . . . . . . . . . . . . . . . . . . . . 62
21. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 58 19.2. Integrity . . . . . . . . . . . . . . . . . . . . . . . . 62
22. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 58 19.3. Interaction with External Routing Domains . . . . . . . . 63
23. References . . . . . . . . . . . . . . . . . . . . . . . . . . 58 20. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 64
23.1. Normative References . . . . . . . . . . . . . . . . . . . 58 20.1. Expert Review: Evaluation Guidelines . . . . . . . . . . . 64
23.2. Informative References . . . . . . . . . . . . . . . . . . 59 20.2. Message Types . . . . . . . . . . . . . . . . . . . . . . 64
Appendix A. Router Configuration . . . . . . . . . . . . . . . . 60 20.3. Message-Type-specific TLV Type Registries . . . . . . . . 64
Appendix B. Example Algorithm for Calculating MPRs . . . . . . . 60 20.4. Message TLV Types . . . . . . . . . . . . . . . . . . . . 65
B.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 61 20.5. Address Block TLV Types . . . . . . . . . . . . . . . . . 66
B.2. MPR Selection Algorithm for each OLSRv2 Interface . . . . 61 21. Contributors . . . . . . . . . . . . . . . . . . . . . . . . . 67
Appendix C. Example Algorithm for Calculating the Routing Set . . 62 22. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 68
C.1. Add Local Symmetric Links . . . . . . . . . . . . . . . . 62 23. References . . . . . . . . . . . . . . . . . . . . . . . . . . 68
C.2. Add Remote Symmetric Links . . . . . . . . . . . . . . . . 63 23.1. Normative References . . . . . . . . . . . . . . . . . . . 68
C.3. Add Attached Networks . . . . . . . . . . . . . . . . . . 64 23.2. Informative References . . . . . . . . . . . . . . . . . . 69
Appendix D. Example Message Layout . . . . . . . . . . . . . . . 65 Appendix A. Example Algorithm for Calculating MPRs . . . . . . . 69
Appendix E. Constraints . . . . . . . . . . . . . . . . . . . . . 67 A.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 70
Appendix F. Flow and Congestion Control . . . . . . . . . . . . . 70 A.2. MPR Selection Algorithm for each OLSRv2 Interface . . . . 71
Appendix B. Example Algorithm for Calculating the Routing Set . . 71
B.1. Local Interfaces and Neighbors . . . . . . . . . . . . . . 72
B.2. Add Neighbor Routers . . . . . . . . . . . . . . . . . . . 72
B.3. Add Remote Routers . . . . . . . . . . . . . . . . . . . . 73
B.4. Add Neighbor Addresses . . . . . . . . . . . . . . . . . . 73
B.5. Add Remote Routable Addresses . . . . . . . . . . . . . . 74
B.6. Add Attached Networks . . . . . . . . . . . . . . . . . . 74
B.7. Add 2-Hop Neighbors . . . . . . . . . . . . . . . . . . . 75
Appendix C. Example Message Layout . . . . . . . . . . . . . . . 76
Appendix D. Constraints . . . . . . . . . . . . . . . . . . . . . 77
Appendix E. Flow and Congestion Control . . . . . . . . . . . . . 81
1. Introduction 1. Introduction
The Optimized Link State Routing protocol version 2 (OLSRv2) is an The Optimized Link State Routing protocol version 2 (OLSRv2) is an
update to OLSRv1 as published in [RFC3626]. Compared to [RFC3626], update to OLSRv1 as published in [RFC3626]. Compared to [RFC3626],
OLSRv2 retains the same basic mechanisms and algorithms, while using OLSRv2 retains the same basic mechanisms and algorithms, while using
a more flexible and efficient signaling framework, and includes some a more flexible and efficient signaling framework, and includes some
simplification of the messages being exchanged. simplification of the messages being exchanged.
OLSRv2 is developed for mobile ad hoc networks. It operates as a OLSRv2 is developed for mobile ad hoc networks. It operates as a
table driven, proactive protocol, i.e. it exchanges topology table driven, proactive protocol, i.e. it exchanges topology
information with other routers in the network regularly. It is an information with other routers in the network regularly. OLSRv2 is
optimization of the classical link state routing protocol. The key an optimization of the classical link state routing protocol. Its
concept used in the protocol is that of MultiPoint Relays (MPRs). key concept is that of MultiPoint Relays (MPRs). Each router selects
Each router selects a set of its neighbor routers (which "cover" all a set of its neighbor routers (which "cover" all of its symmetrically
of its symmetrically connected 2-hop neighbor routers) as MPRs. connected 2-hop neighbor routers) as MPRs. MPRs are then used to
Control traffic is flooded through the network using hop by hop achieve both flooding reduction and topology reduction.
forwarding, but where a router only needs to forward control traffic
directly received from its MPR selectors (routers which have selected
it as an MPR). This mechanism, denoted "MPR flooding", provides an
efficient mechanism for information distribution within the MANET by
reducing the number of transmissions required.
Routers selected as MPRs also have a special responsibility when Flooding reduction is achieved by control traffic being flooded
declaring link state information in the network. A sufficient through the network using hop by hop forwarding, but with a router
requirement for OLSRv2 to provide shortest (lowest hop count) path only needing to forward control traffic which is first received
routes to all destinations is that routers declare link state directly from one of the routers which have selected it as an MPR
information for their MPR selectors, if any. Additional available (its "MPR selectors"). This mechanism, denoted "MPR flooding",
link state information may be transmitted, e.g. for redundancy. provides an efficient mechanism for information distribution within
Thus, as well as being used to facilitate MPR flooding, use of MPRs the MANET by reducing the number of transmissions required.
allows the reduction of the number and size of link state messages,
and MPRs are used as intermediate routers in multi-hop routes. Topology redction is achieved by a mechanism where the routers
selected as MPRs have a special responsibility when declaring link
state information in the network. A sufficient requirement for
OLSRv2 to provide shortest (lowest hop count) routes to all
destinations is that routers declare link state information for their
MPR selectors, if any. Routers which are not selected as MPRs need
not send any link state information. Additional available link state
information may be transmitted, e.g. for redundancy. Thus the use of
MPRs allows reduction of the number and the size of link state
messages, and in the amount of link state information maintained in
each router. Based on this reduced link state information, MPRs are
used as intermediate routers in multi-hop routes.
A router selects MPRs from among its one hop neighbors connected by A router selects MPRs from among its one hop neighbors connected by
"symmetric", i.e. bidirectional, links. Therefore, selecting routes "symmetric", i.e. bidirectional, links. Therefore, selecting routes
through MPRs automatically avoids the problems associated with data through MPRs avoids the problems associated with data packet transfer
packet transfer over unidirectional links (such as the problem of not over unidirectional links (such as the problem of not getting link
getting link layer acknowledgments at each hop, for link layers layer acknowledgments at each hop, for link layers employing this
employing this technique). technique).
OLSRv2 uses and extends [NHDP] and uses [RFC5444], [RFC5497] and, OLSRv2 uses and extends [NHDP] and uses [RFC5444], [RFC5497] and,
optionally, [RFC5148]. (These other protocols and specifications optionally, [RFC5148]. These other protocols and specifications were
were all originally created as part of OLSRv2, but have been all originally created as part of OLSRv2, but have been specified
specified separately for wider use.) separately for wider use.
OLSRv2 makes no assumptions about the underlying link layer. OLSRv2 makes no assumptions about the underlying link layer. OLSRv2,
However, OLSRv2, through its use of [NHDP], may use link layer through its use of [NHDP], may use link layer information and
information and notifications when available and applicable. notifications when available and applicable.
OLSRv2, as OLSRv1, inherits its concept of forwarding and relaying OLSRv2, as OLSRv1, inherits its concept of forwarding and relaying
from HIPERLAN (a MAC layer protocol) which is standardized by ETSI from HIPERLAN (a MAC layer protocol) which is standardized by ETSI
[HIPERLAN], [HIPERLAN2]. [HIPERLAN], [HIPERLAN2].
2. Terminology 2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in "OPTIONAL" in this document are to be interpreted as described in
skipping to change at page 6, line 27 skipping to change at page 6, line 32
"Address Block", "TLV Block", and "TLV", are to be interpreted as "Address Block", "TLV Block", and "TLV", are to be interpreted as
described there. described there.
All terms introduced in [NHDP], including "interface", "MANET All terms introduced in [NHDP], including "interface", "MANET
interface", "address", "symmetric link", "symmetric 1-hop neighbor", interface", "address", "symmetric link", "symmetric 1-hop neighbor",
"symmetric 2-hop neighbor", "constant", "interface parameter", and "symmetric 2-hop neighbor", "constant", "interface parameter", and
"router parameter", are to be interpreted as described there. "router parameter", are to be interpreted as described there.
Additionally, this document uses the following terminology: Additionally, this document uses the following terminology:
Router - A MANET router which implements the Optimized Link State Router - A MANET router which implements the protocol specified in
Routing protocol version 2 as specified in this document. this document.
OLSRv2 interface - A MANET interface, running OLSRv2. Note that all OLSRv2 interface - A MANET interface running this protocol.
references to MANET interfaces in [NHDP] refer to OLSRv2
interfaces when using [NHDP] to support OLSRv2. Routable address - An address which may be used as the destination
of a packet. A router MUST be able to distinguish a routable
address from a non-routable address by direct inpsection of the
address, based on global scope address allocations by IANA and/or
administrative configuration. Broadcast, multicast and anycast
addresses, and addresses which are limited in scope to less than
the entire MANET, MUST NOT be considered as routable addresses.
Originator address - An address which is unique (within the MANET) Originator address - An address which is unique (within the MANET)
to the selecting router. A router MUST select an originator to a router. A router MUST select an originator address; it MAY
address; it MAY choose one of its interface addresses as its choose one of its interface addresses as its originator address.
originator address. An originator address MUST NOT have a prefix If it selects a routable address then this MUST be one which this
length. An originator address MUST be included in all messages router will accept as destination. An originator address MUST NOT
generated by this protocol, and as specified in [RFC5444]. have a prefix length.
Message originator address - The originator address of the router
which created a message, as deduced from that message by its
recipient. The message originator address will usually be
included in the message as its <msg-orig-addr> element as defined
in [RFC5444]. However an exceptional case in a HELLO message is
also allowed by this specification when a router only uses a
single address. All messages used in this specification,
including HELLO messages defined in [NHDP], MUST have a message
originator address.
Willingness - A numerical value between WILL_NEVER and WILL_ALWAYS Willingness - A numerical value between WILL_NEVER and WILL_ALWAYS
(both inclusive), which represents the router's willingness to be (both inclusive), which represents the router's willingness to be
selected as an MPR. selected as an MPR.
Willing symmetric 1-hop neighbor - A symmetric 1-hop neighbor of Willing symmetric 1-hop neighbor - A symmetric 1-hop neighbor of
this router which has willingness not equal to WILL_NEVER. this router which has willingness not equal to WILL_NEVER.
Symmetric 1-hop neighbor through OLSRv2 interface I - A symmetric
1-hop neighbor of the router via a symmetric link using OLSRv2
interface I of the router.
Symmetric strict 2-hop neighbor - A router, X, is a symmetric strict Symmetric strict 2-hop neighbor - A router, X, is a symmetric strict
2-hop neighbor of a router Y, if router X is a symmetric 2-hop 2-hop neighbor of a router Y, if router X is a symmetric 2-hop
neighbor of router Y and if router X is not also a willing neighbor of router Y and if router X is not also a willing
symmetric 1-hop neighbor of router Y. symmetric 1-hop neighbor of router Y.
Symmetric strict 2-hop neighbor through OLSRv2 interface I - A Symmetric strict 2-hop neighbor through OLSRv2 interface I - A
symmetric strict 2-hop neighbor of the router with OLSRv2 symmetric strict 2-hop neighbor of the router which is a symmetric
interface I which is a symmetric 1-hop neighbor of a willing 1-hop neighbor of a willing symmetric 1-hop neighbor through
symmetric 1-hop neighbor of that router via a symmetric link using
OLSRv2 interface I. The router MAY elect to consider only OLSRv2 interface I. The router MAY elect to consider only
information received over OLSRv2 interface I in making this information received over OLSRv2 interface I in making this
determination. determination.
Symmetric strict 2-hop neighborhood - The symmetric strict 2-hop Symmetric strict 2-hop neighborhood - The symmetric strict 2-hop
neighborhood of a router X is the set of symmetric strict 2-hop neighborhood of a router X is the set of symmetric strict 2-hop
neighbors of router X. neighbors of router X.
Multipoint relay (MPR) - A router, X, is an MPR for a router, Y, if Multipoint relay (MPR) - A router, X, is an MPR for a router, Y, if
router Y has selected router X to "re-transmit" all the broadcast router Y has selected router X to "re-transmit" all the broadcast
messages that it receives from router X, provided that the message messages that it receives from router X, provided that the message
is not a duplicate, and that the hop limit field of the message is is not a duplicate, and that the hop limit field of the message is
greater than one. greater than one.
MPR selector - A router, Y, is an MPR selector of router X if router MPR selector - A router, Y, is an MPR selector of router X if router
Y has selected router X as MPR. Y has selected router X as MPR.
MPR flooding - The optimized MANET-wide information distribution MPR flooding - The optimized MANET-wide information distribution
mechanism, employed by this protocol, in which a message is mechanism, employed by this protocol, in which a message is
relayed by only a reduced subset of the routers in the network. relayed by only a reduced subset of the routers in the network.
MPR flooding is the mechanism by which flooding reduction is
achieved.
This document employs the same notational conventions as in [RFC5444] This document employs the same notational conventions as in [RFC5444]
and [NHDP]. and [NHDP].
3. Applicability Statement 3. Applicability Statement
The Optimized Link State Routing protocol version 2 (OLSRv2): This protocol:
o Is a proactive routing protocol for mobile ad hoc networks o Is a proactive routing protocol for mobile ad hoc networks
(MANETs) [RFC2501]. (MANETs) [RFC2501].
o Is designed to work in networks with a dynamic topology, and in o Is designed to work in networks with a dynamic topology, and in
which messages may be lost, such as due to collisions in wireless which messages may be lost, such as due to collisions in wireless
networks. networks.
o Supports routers that each have one or more participating OLSRv2 o Supports routers that each have one or more participating OLSRv2
interfaces. The set of a router's interfaces may change over interfaces. The set of a router's interfaces may change over
time. Each OLSRv2 interface may have one or more addresses (which time. Each OLSRv2 interface may have one or more addresses (which
may have prefix lengths), and these may also be dynamically may have prefix lengths), and these may also be dynamically
changing. changing.
o Enables hop-by-hop routing, i.e., each router can use its local o Enables hop-by-hop routing, i.e., each router can use its local
information provided by OLSRv2 to route packets. information provided by this protocol to route packets.
o Continuously maintains routes to all destinations in the network, o Continuously maintains routes to all destinations in the network,
i.e., routes are instantly available and data traffic is subject i.e., routes are instantly available and data traffic is subject
to no delays due to route discovery. Consequently, no data to no delays due to route discovery. Consequently, no data
traffic buffering is required. traffic buffering is required.
o Supports routers which have non-OLSRv2 interfaces which may be o Supports routers which have non-OLSRv2 interfaces which may be
local to a router or which can serve as gateways towards other local to a router or which can serve as gateways towards other
networks. networks.
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dense a network, the more optimization can be achieved by using dense a network, the more optimization can be achieved by using
MPRs, compared to the classic link state algorithm. MPRs, compared to the classic link state algorithm.
o Uses the message format specified in [RFC5444]. This includes the o Uses the message format specified in [RFC5444]. This includes the
definition of a TC Message Type, used for MANET wide signaling of definition of a TC Message Type, used for MANET wide signaling of
network topology information. network topology information.
o Allows "external" and "internal" extensibility as enabled by o Allows "external" and "internal" extensibility as enabled by
[RFC5444]. [RFC5444].
o Uses [NHDP] for discovering each OLSRv2 router's 1-hop and o Uses [NHDP] for discovering each router's 1-hop and symmetric
symmetric 2-hop neighbors, and extends [NHDP] by addition of MPR 2-hop neighbors, and extends [NHDP] by addition of MPR and
and willingness information. willingness information.
o Is designed to work in a completely distributed manner, and does o Is designed to work in a completely distributed manner, and does
not depend on any central entity. not depend on any central entity.
4. Protocol Overview and Functioning 4. Protocol Overview and Functioning
The objective of OLSRv2 is, for each router to, independently: The objective of this protocol is for each router to, independently:
o Identify all destinations in the network. o Identify all destinations in the network.
o Identify a sufficient subset of links in the network, in order o Identify a sufficient subset of links in the network, in order
that shortest paths can be calculated to all available that shortest paths can be calculated to all available
destinations. destinations.
o Provide a Routing Set, containing these shortest paths from this o Provide a Routing Set, containing these shortest paths from this
router to all destinations. router to all destinations (routable addresses and local links).
These objectives are achieved for each router by: 4.1. Overview
These objectives are achieved, for each router, by:
o Using [NHDP] to identify symmetric 1-hop neighbors and symmetric o Using [NHDP] to identify symmetric 1-hop neighbors and symmetric
2-hop neighbors. 2-hop neighbors.
o Independently selecting MPRs from among its symmetric 1-hop o Independently selecting MPRs from among its symmetric 1-hop
neighbors such that all symmetric 2-hop neighbors are reachable neighbors such that all symmetric 2-hop neighbors are reachable
via at least one symmetric 1-hop neighbor. An analysis and via at least one symmetric 1-hop neighbor. An analysis and
examples of MPR selection algorithms is given in [MPR], a examples of MPR selection algorithms is given in [MPR], a
suggested algorithm is included in this specification. Note that suggested algorithm is included in this specification. Note that
it is not necessary for routers to use the same algorithm to it is not necessary for routers to use the same algorithm in order
interoperate. to interoperate in the same MANET.
o Signaling its MPR selection by extending [NHDP] to include this o Signaling its MPR selection by extending [NHDP] to include this
information in outgoing HELLO messages. information in outgoing HELLO messages, by the addition of MPR
Address Block TLV(s) associated with appropriate addresses.
o Extracting its MPR selectors from received HELLO messages. o Extracting its MPR selectors from received HELLO messages, using
the included MPR Address Block TLV(s).
o Reporting its willingness to be an MPR in HELLO messages. The o Reporting its willingness to be an MPR in HELLO messages, by the
router's willingness to be an MPR indicates how willing it is to addition on an MPR_WILLING Message TLV. The router's willingness
participate in MPR flooding and to be an intermediate node for to be an MPR indicates how willing it is to participate in MPR
routing. A node can absolutely decline to perform either role. flooding and to be an intermediate node for routing. A node can
absolutely decline to perform either role.
o Periodically signaling links between MPR selectors and itself o Periodically signaling links between MPR selectors and itself
throughout the MANET, by using TC (Topology Control) messages, throughout the MANET, by using TC (Topology Control) messages,
defined in this specification. defined in this specification.
o Diffusing TC messages by using flooding reduction mechanism, o Diffusing TC messages by using flooding reduction mechanism,
denoted "MPR flooding": only the MPRs of a router will retransmit denoted "MPR flooding": only the MPRs of a router will retransmit
messages received from (i.e., originated or last relayed by) that messages received from (i.e., originated or last relayed by) that
router. router.
Note that the indicated extensions to [NHDP] are of forms permitted
by that specification.
This specification defines, in turn: This specification defines, in turn:
o Parameters and constants used by OLSRv2, in addition to those o Parameters and constants used by this protocol, in addition to
specified in [NHDP]. Parameters used by OLSRv2 may be, where those specified in [NHDP]. Parameters used by this protocol may,
appropriate, specific to a given OLSRv2 interface, or to an OLSRv2 where appropriate, be specific to a given OLSRv2 interface, or to
router. OLSRv2 allows all parameters to be changed dynamically, a router. This protocol allows all parameters to be changed
and to be set independently for each OLSRv2 router or OLSRv2 dynamically, and to be set independently for each router or each
interface, as appropriate. OLSRv2 interface, as appropriate.
o Extensions to the Information Bases specified in [NHDP], and new o Extensions to the Information Bases specified in [NHDP].
Topology Information Base and Processing and Forwarding
Information Base.
o An Address Block TLV, to be included within the HELLO messages of o Two new Information Bases: the Topology Information Base and the
[NHDP], allowing a router to signal MPR selection. Received Message Information Base.
o A Message TLV, to be included within the HELLO messages of [NHDP], o A requirement for each router to have an originator address to be
included in the HELLO messages of [NHDP].
o A Message TLV, to be included in the HELLO messages of [NHDP],
allowing a router to indicate its willingness to be an MPR. allowing a router to indicate its willingness to be an MPR.
o The MPR flooding mechanism. o An Address Block TLV, to be included in the HELLO messages of
[NHDP], allowing a router to signal its MPR selection.
o The format of the TC message that is used for MANET wide o The MPR flooding mechanism, including the inclusion of message
signaling. originator address and sequence number to manage duplicate
messages.
o TC messages, which are used for MANET wide signaling (using MPR
flooding) of selected topology (link state) information.
o The specification of new Message TLVs and Address Block TLVs which
are used in TC messages.
o The generation of TC messages from the appropriate information in o The generation of TC messages from the appropriate information in
the Information Bases. the Information Bases.
o The updating of the Information Bases according to received TC o The updating of the Topology Information Base according to
messages. received TC messages.
o The response to other events, such as the expiration of o The response to other events, such as the expiration of
information in the Information Bases. information in the Information Bases.
OLSRv2 inherits the stability of a link state algorithm and has the This protocol inherits the stability of a link state algorithm and
advantage of having routes immediately available when needed due to has the advantage of having routes immediately available when needed,
its proactive nature. due to its proactive nature.
OLSRv2 only interacts with IP through routing table management, and This protocol only interacts with IP through routing table
the use of the sending IP address for IP datagrams containing OLSRv2 management, and the use of the sending IP address for IP datagrams
messages. containing OLSRv2 packets.
4.1. Routers and Interfaces 4.2. Routers and Interfaces
In order for a router to participate in a MANET, it MUST have at In order for a router to participate in a MANET, it MUST have at
least one, and possibly more, OLSRv2 interfaces. Each OLSRv2 least one, and possibly more, OLSRv2 interfaces. Each OLSRv2
interface: interface:
o Is configured with one or more addresses, as specified in [NHDP]. o Is configured with one or more addresses, as specified in [NHDP].
These addresses MUST be unique within the MANET. These addresses MUST each be unique within the MANET and MUST
include any address that will be used as the sending address of
any IP packet sent on this OLSRv2 interface.
o Has a number of interface parameters, adding to those specified in o Has a number of interface parameters, adding to those specified in
[NHDP]. [NHDP].
o Has an Interface Information Base, extending that specified in o Has an Interface Information Base, extending that specified in
[NHDP]. [NHDP].
o Generates and processes HELLO messages according to [NHDP], o Generates and processes HELLO messages according to [NHDP],
extended as specified in Section 9 and Section 10. extended as specified in Section 9 and Section 10.
In addition to a set of MANET interfaces as described above, each In addition to a set of OLSRv2 interfaces as described above, each
router: router:
o May have one or more non-OLSRv2 interfaces and/or local attached
networks which this router can accept packets destined for. All
routable addresses of the router for which it is to accept packets
as destination MUST be used as an (OLSRv2 or non-OLSRv2) interface
address or of a local attached network.
o Has a number of router parameters, adding to those specified in o Has a number of router parameters, adding to those specified in
[NHDP]. [NHDP].
o Has a Local Information Base, extending that specified in [NHDP]. o Has a Local Information Base, extending that specified in [NHDP],
including selection of an originator address and recording any
locally attached networks.
o Has a Neighbor Information Base, extending that specified in o Has a Neighbor Information Base, extending that specified in
[NHDP]. [NHDP] to record MPR selection and advertisement information.
o Has a Topology Information Base, recording information required o Has a Topology Information Base, recording information received in
for generation and processing of TC messages. TC messages and derived therefrom.
o Has a Processing and Forwarding Information Base, recording o Has a Received Message Information Base, recording information
information required for MPR flooding, and to ensure that each TC about received messages to ensure that each TC message is only
message is only processed once by a router. processed once, and forwarded at most once on each OLSRv2
interface, by a router.
o Generates and processes TC messages. o Generates and processes TC messages.
4.2. Information Base Overview 4.3. Information Base Overview
Each router maintains the Information Bases described in the Each router maintains the Information Bases described in the
following sections. These are used for describing the protocol in following sections. These are used for describing the protocol in
this document. An implementation of this protocol MAY maintain this this document. An implementation of this protocol MAY maintain this
information in the indicated form, or in any other organization which information in the indicated form, or in any other organization which
offers access to this information. In particular, note that it is offers access to this information. In particular, note that it is
not necessary to remove Tuples from Sets at the exact time indicated, not necessary to remove Tuples from Sets at the exact time indicated,
only to behave as if the Tuples were removed at that time. only to behave as if the Tuples were removed at that time.
4.2.1. Local Information Base 4.3.1. Local Information Base
The Local Information Base is specified in [NHDP] and contains a The Local Information Base is specified in [NHDP] and contains a
router's local configuration. It is extended in this specification router's local configuration. It is extended in this specification
to also contain a router's: to also record an originator address and to include a router's:
o Originator Set, containing addresses that were recently used as o Originator Set, containing addresses that were recently used as
this router's originator address. this router's originator address, and is used to enable a router
to recognize and discard control traffic which was originated by
the router itself.
o Local Attached Network Set, containing addresses of networks to o Local Attached Network Set, containing addresses of networks to
which this router can act as a gateway. which this router can act as a gateway, and advertises in its TC
messages.
The Originator Set is used to enable a router to recognize and
discard control traffic which was originated by the router itself.
The Local Attached Network Set is used to enable a router to include
advertisement of reachability to a network, for which the router can
act as a gateway, when generating TC messages.
4.2.2. Interface Information Bases 4.3.2. Interface Information Bases
The Interface Information Bases, one for each OLSRv2 interface, are The Interface Information Bases, one for each OLSRv2 interface, are
specified in [NHDP]. In addition to the uses in [NHDP], information specified in [NHDP]. In addition to the uses in [NHDP], information
recorded in the Interface Information Bases is used for completing recorded in the Interface Information Bases is used for completing
the Routing Set. the Routing Set.
4.2.3. Neighbor Information Base 4.3.3. Neighbor Information Base
The Neighbor Information Base is specified in [NHDP], and is extended The Neighbor Information Base is specified in [NHDP], and is extended
to also record the willingness of each neighbor to be an MPR, as well to also record each neighbor's originator address, the willingness of
as this router's MPR relationships with each neighbor. Specifically, each neighbor to be an MPR, as well as this router's MPR
each Neighbor Tuple is extended to record whether that neighbor is an relationships with each neighbor (whether an MPR and/or an MPR
MPR and/or MPR selector of this router, as well as the neighbor's selector of that neighbor) and whether that neighbor is to be
willingness to be an MPR. advertised in TC messages.
In addition to the uses in [NHDP], information recorded in the A router selects some of its symmetric 1-hop neighbors as MPRs (see
Neighbor Information Base is used to determine inclusion of the MPR Section 14). That selection is recorded in the Neighbor Set. This
Address Block TLV, defined in this document, as well as for selection is then reported in the router's HELLO messages, extending
populating the Advertised Neighbor Set and the Relay Sets of a the specification in [NHDP], by using an MPR Address Block TLV. In
router. making that selection a router MUST consider its 1-hop neighbors'
willingness to be an MPR, which (unless having default value) is
reported using an Address Block TLV in HELLO messages and recorded in
the receiving router's Neighbor Set.
4.2.4. Topology Information Base A router also records in the Neighbor Set which symmetric 1-hop
neighbors have selected it as an MPR (i.e. its MPR selectors). This
is determined from the MPR TLVs in received HELLO messages. It also
records which symmetric 1-hop neighbors that it is to advertise
connectivity to in its TC messages; this MUST include all of its MPR
selectors.
The Topology Information Base contains: The Neighbor Set finally records each 1-hop neighbor's originator
address, as included in its HELLO messages in an extension to [NHDP].
This, and other information in the Neighbor Set, including each 1-hop
neighbor's routable addresses, is used in advertising the selected
symmetric 1-hop neighbors in TC messages.
o An Advertised Neighbor Set, describing the symmetric 1-hop 4.3.4. Topology Information Base
neighbors of this router that are to be advertised in TC messages.
This set contains at least the MPR selectors of this router, and
is associated with an Advertised Neighbor Sequence Number (ANSN),
which is incremented for each change made to this Advertised
Neighbor Set.
o An Advertising Remote Router Set, describing each other router The purpose of the Topology Information Base is to record information
from which TC messages have been received. used, in addition to that in the Local Information Base, the
Interface Information Bases and the Neighbor Information Base, to
construct the Routing Set (which is also included in the Topology
Information Base).
o A Topology Set, recording links between routers in the MANET, as This specification describes the calculation of the Routing Set based
described by received TC messages. on a Topology Graph constructed in two phases. First, a "backbone"
graph representing the routers in the MANET, and the connectivity
between them, is constructed from the Local Information Base, the
Neighbor Information Base and the Router Topology Set in the Topology
Information Base. Second, this graph is "decorated" with additional
destination addresses using the Local Information Base, and the
Routable Address Topology Set and the Attached Network Set in the
Topology Information Base.
o An Attached Network Set, recording networks to which a remote The Topology Graph does not need to be recorded in the Topology
router has advertised that it may act as a gateway. Information Base, it can either be constructed as required when the
Routing Set is to be changed, or need not be explicitly constructed
(as illustrated in Appendix B. An implementation MAY construct and
retain the Topology Graph if preferred.
o A Routing Set, calculated based on the Interface Information The Topology Information Base in each router contains:
Bases, the Neighbor Information Base, and the Topology Information
Base to record routes from this router to all available
destinations, The routing table is to be updated from this Routing
Set. (A router MAY choose to use any or all destination addresses
in the Routing Set to update the routing table, this selection is
outside the scope of OLSRv2.)
The Advertised Neighbor Set is used for when generating TC messages; o An Advertising Remote Router Set, recording each other router from
the Advertised Neighbor Sequence Number is included in each TC which TC messages have been received. This is used in order to
message, thereby allowing a receiving router to identify if a TC determine if a received TC messages contains fresh or outdated
message contains fresh or outdated information. information; the TC message is ignored in the latter case.
The Advertising Remote Router Set, the Topology Set and the Attached o A Router Topology Set, recording links between routers in the
Network Set are all updated upon receipt of TC messages, and are used MANET, as described by received TC messages.
when determining the contents of the Routing Set.
4.2.5. Processing and Forwarding Information Base o A Routable Address Topology Set, recording routable addresses in
the MANET (available as packet destinations) and from which other
router these addresses can be directly reached (i.e. in a single
IP hop) as reported by received TC messages.
The Processing and Forwarding Information Base contains: o An Attached Network Set, recording networks to which a remote
router has advertised that it may act as a gateway. These
networks may be reached in one or more IP hops.
o A Received Set, describing TC messages received by this router. o A Routing Set, recording routes from this router to all available
destinations. The IP routing table is to be updated using this
Routing Set. (A router MAY choose to use any or all destination
addresses in the Routing Set to update the IP routing table, this
selection is outside the scope of this protocol.)
4.3.5. Received Message Information Base
The Received Message Information Base in each router contains:
o A Received Set for each OLSRv2 interface, describing TC messages
received by this router on that OLSRv2 interface.
o A Processed Set, describing TC messages processed by this router. o A Processed Set, describing TC messages processed by this router.
o A Forwarded Set, describing TC messages forwarded by this router. o A Forwarded Set, describing TC messages forwarded by this router.
o A Relay Set for each OLSRv2 interface, describing the set of The Received Message Information Base serves the MPR flooding
neighbor routers from which received traffic is to be relayed (if mechanism by ensuring that received messages are forwarded at most
otherwise appropriate). once by a router, and also ensures that received messages are
processed exactly once by a router.
The Processing and Forwarding Information Base serves the MPR
flooding mechanism by enabling that received messages are forwarded
at most once, by a router. and also ensures that received messages
are processed exactly once.
4.3. Signaling Overview 4.4. Signaling Overview
OLSRv2 uses the neighborhood discovery protocol [NHDP], and generates This protocol generates and processes HELLO messages according to
and processes HELLO messages according to [NHDP], extended according [NHDP], extended according to Section 9 and Section 10 of this
to Section 9 and Section 10. specification to include an originator address and MPR selection
information.
OLSRv2 specifies a single message type, the TC message. This protocol specifies a single message type, the TC message.
OLSRv2 does not require reliable transmission of TC messages; each This protocol is tolerant of unreliable transmissions of TC messages;
router sends TC messages periodically, and can therefore sustain a each router sends TC messages periodically, and can therefore sustain
reasonable loss of some such messages. Such losses may occur a reasonable loss of some such messages. Such losses may occur more
frequently in wireless networks due to collisions or other frequently in wireless networks due to collisions or other
transmission problems. OLSRv2 MAY use "jitter", randomized transmission problems. This protocol MAY use "jitter", randomized
adjustments to message transmission times, to reduce the incidence of adjustments to message transmission times, to reduce the incidence of
collisions as specified in [RFC5148]. collisions as specified in [RFC5148].
OLSRv2 does not require sequenced delivery of TC messages. Each TC This protocol is tolerant of out of sequence delivery of TC messages
message contains a sequence number which is incremented when the due to in transit message reordering (possibly due to message
message contents change. Thus the recipient of a TC message can, if alternative routing by flooding and message loss). Each router
required, easily identify which information is more recent, even if maintains an Advertised Neighbor Sequence Number (ANSN) which is
messages have been re-ordered while in transmission. incremented when its recorded neighbor information that is to be
included in its TC messages changes. This ANSN is included in the
router's TC messages. The recipient of a TC message can used this
included ANSN to identify which of the information it has received is
most recent, even if messages have been re-ordered while in transit.
Only the most recent information received is used, older information
received later is discarded.
TC messages may be "complete" or "incomplete". A complete TC message TC messages may be "complete" or "incomplete". A complete TC message
contains at least the set of addresses of the originating router's advertises all of the originating router's MPR selectors, it may also
MPR selectors. Complete TC messages are generated periodically (and advertise other symmetric 1-hop neighbors. Complete TC messages are
also, optionally, in response to neighborhood changes). Incomplete generated periodically (and also, optionally, in response to
TC messages may be used to report additions to advertised information neighborhood changes). Incomplete TC messages may be used to report
without repeating unchanged information. additions to advertised information without repeating unchanged
information.
TC messages, and HELLO messages as extended by this specification,
include an originator address for the router that created the
message. A TC message reports both the originator addresses and
routable addresses of its advertised neighbors, distinguishing the
two using a TLV for this purpose (an address may be both).
TC messages also report the originator's locally attached networks.
TC messages are MPR flooded throughout the MANET. A router TC messages are MPR flooded throughout the MANET. A router
retransmits a TC message only if it is received from (i.e., retransmits a TC message only if it is received from (i.e.,
originated from or was last relayed by) one of that router's MPR originated from or was last relayed by) one of that router's MPR
selectors. selectors.
Some TC messages may be MPR flooded over only part of the network, Some TC messages may be MPR flooded over only part of the network,
allowing a router to ensure that nearer routers are kept more up to e.g., allowing a router to ensure that nearer routers are kept more
date than distant routers, such as is used in Fisheye State Routing up to date than distant routers, such as is used in Fisheye State
[FSR] and Fuzzy Sighted Link State routing [FSLS]. This is enabled Routing [FSR] and Fuzzy Sighted Link State routing [FSLS]. This is
in OLSRv2 by using [RFC5497]. enabled using [RFC5497].
4.5. Routing Set
The purpose of the Routing Set is to determine and record routes
(local interface address and next hop interface address) to all
possible routable addresses and of all destinations that are local,
i.e. within one hop, to the router (whether using routable addresses
or not). Only symmetric links are used in such routes.
It is intended that the Routing Set can be used for packet routing,
by using its contents to update IP's routing tables. That update,
and whether any Routing Tuples are not used in IP's routing table, is
outside the scope of this specification.
The signaling in this specification has been designed so that a
"backbone" Topology Graph of routers, each identified by its
originator address, with at most one direct connection between any
pair of routers, can be constructed (from the Neighbor Set and the
Router Topology Set) using a suitable minimum path length algorithm,
and then this Topology Graph can have other addresses (routable, or
of symmetric 1-hop neighbors) added to it (using the Interface
Information Base, the Routable Address Topology Set and the Attached
Network Set).
5. Protocol Parameters and Constants 5. Protocol Parameters and Constants
The parameters and constants used in this specification are those The parameters and constants used in this specification are those
defined in [NHDP] plus those defined in this section. The separation defined in [NHDP] plus those defined in this section. The separation
in [NHDP] into interface parameters, router parameters and constants in [NHDP] into interface parameters, router parameters and constants
is also used in OLSRv2, however all but one (RX_HOLD_TIME) of the is also used in this specification, however all but one
parameters added by OLSRv2 are router parameters. Parameters may be (RX_HOLD_TIME) of the parameters added by this protocol are router
classified into the following categories: parameters. Parameters may be categorized as follows:
o Local history times o Local history times
o Message intervals o Message intervals
o Advertised information validity times o Advertised information validity times
o Received message validity times o Received message validity times
o Jitter times o Jitter times
o Hop limits o Hop limits
o Willingness o Willingness
In addition, constants for particular cases of a router's willingness In addition, constants for particular cases of a router's willingness
to be an MPR are defined. These parameters and constants are to be an MPR are defined. These parameters and constants are
detailed in the following sections. As for the parameters in [NHDP], detailed in the following sections. As for the parameters in [NHDP],
parameters defined in this document may be changed dynamically by a parameters defined in this document may be changed dynamically by a
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o Hop limits o Hop limits
o Willingness o Willingness
In addition, constants for particular cases of a router's willingness In addition, constants for particular cases of a router's willingness
to be an MPR are defined. These parameters and constants are to be an MPR are defined. These parameters and constants are
detailed in the following sections. As for the parameters in [NHDP], detailed in the following sections. As for the parameters in [NHDP],
parameters defined in this document may be changed dynamically by a parameters defined in this document may be changed dynamically by a
router, and need not be the same on different routers, even in the router, and need not be the same on different routers, even in the
same MANET, or on different interfaces of the same router (for same MANET, or, for interface parameters, on different interfaces of
interface parameters). the same router.
5.1. Protocol and Port Numbers 5.1. Protocol and Port Numbers
This protocol specifies TC messages, which are included in packets as This protocol specifies TC messages, which are included in packets as
defined by [RFC5444]. These packets may be sent either using the defined by [RFC5444]. These packets may be sent either using the
"manet" protocol number or the "manet" well-known UDP port number, as "manet" protocol number or the "manet" well-known UDP port number, as
specified in [RFC5498]. specified in [RFC5498].
TC messages and HELLO messages [NHDP] SHOULD, in a given deployment TC messages and HELLO messages [NHDP] SHOULD, in a given deployment
of OLSRv2, both be using the same of either of IP or UDP, in order of this protocol, both be using the same of either of IP or UDP, in
that it is possible to combine messages of both protocols into the order that it is possible to combine messages of both protocols into
same [RFC5444] packet. the same [RFC5444] packet for transmission.
5.2. Multicast Address 5.2. Multicast Address
This protocol specifies HELLO messages, which are included in packets This protocol specifies TC messages, which are included in packets as
as defined by [RFC5444]. These packets may be locally transmitted defined by [RFC5444]. These packets may be locally transmitted using
using the link local multicast address "LL-MANET-Routers", as the link local multicast address "LL-MANET-Routers", as specified in
specified in [RFC5498]. [RFC5498].
5.3. Local History Times 5.3. Local History Times
The following router parameter manages the time for which local The following router parameter manages the time for which local
information is retained: information is retained:
O_HOLD_TIME - is used to define the time for which a recently used O_HOLD_TIME - is used to define the time for which a recently used
and replaced originator address is used to recognize the router's and replaced originator address is used to recognize the router's
own messages. own messages.
The following constraint applies to this parameter: The following constraint applies to this parameter:
o O_HOLD_TIME >= 0 o O_HOLD_TIME >= 0
5.4. Message Intervals 5.4. Message Intervals
The following router parameters regulate TC message transmissions by The following router parameters regulate TC message transmissions by
a router. TC messages are usually sent periodically, but MAY also be a router. TC messages are usually sent periodically, but MAY also be
sent in response to changes in the router's Advertised Neighbor Set sent in response to changes in the router's Neighbor Set and/or Local
and Local Attached Network Set. With a larger value of the parameter Attached Network Set. With a larger value of the parameter
TC_INTERVAL, and a smaller value of the parameter TC_MIN_INTERVAL, TC TC_INTERVAL, and a smaller value of the parameter TC_MIN_INTERVAL, TC
messages may more often be transmitted in response to changes in a messages may more often be transmitted in response to changes in a
highly dynamic network. However because a router has no knowledge highly dynamic network. However because a router has no knowledge
of, for example, routers remote to it (i.e. beyond 2 hops away) of, for example, routers remote to it (i.e. beyond 2 hops away)
joining the network, TC messages MUST NOT be sent purely joining the network, TC messages MUST NOT be sent purely
responsively. responsively.
TC_INTERVAL - is the maximum time between the transmission of two TC_INTERVAL - is the maximum time between the transmission of two
successive TC messages by this router. When no TC messages are successive TC messages by this router. When no TC messages are
sent in response to local network changes (by design, or because sent in response to local network changes (by design, or because
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information is recorded, in order that the message is not information is recorded, in order that the message is not
forwarded again if received again. forwarded again if received again.
The following constraints apply to these parameters: The following constraints apply to these parameters:
o RX_HOLD_TIME > 0 o RX_HOLD_TIME > 0
o P_HOLD_TIME > 0 o P_HOLD_TIME > 0
o F_HOLD_TIME > 0 o F_HOLD_TIME > 0
o All of these parameters SHOULD be greater than the maximum o All of these parameters SHOULD be greater than the maximum
difference in time that a message may take to traverse the MANET, difference in time that a message may take to traverse the MANET,
taking into account any message forwarding jitter as well as taking into account any message forwarding jitter as well as
propagation, queuing, and processing delays. propagation, queuing, and processing delays.
5.7. Jitter 5.7. Jitter
If jitter, as defined in [RFC5148], is used then these parameters are If jitter, as defined in [RFC5148], is used then the governing jitter
as follows: parameters are as follows:
TP_MAXJITTER - represents the value of MAXJITTER used in [RFC5148] TP_MAXJITTER - represents the value of MAXJITTER used in [RFC5148]
for periodically generated TC messages sent by this router. for periodically generated TC messages sent by this router.
TT_MAXJITTER - represents the value of MAXJITTER used in [RFC5148] TT_MAXJITTER - represents the value of MAXJITTER used in [RFC5148]
for externally triggered TC messages sent by this router. for externally triggered TC messages sent by this router.
F_MAXJITTER - represents the default value of MAXJITTER used in F_MAXJITTER - represents the default value of MAXJITTER used in
[RFC5148] for messages forwarded by this router. However before [RFC5148] for messages forwarded by this router. However before
using F_MAXJITTER a router MAY attempt to deduce a more using F_MAXJITTER a router MAY attempt to deduce a more
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property. For example the repeating pattern (255 4 4) satisfies this property. For example the repeating pattern (255 4 4) satisfies this
property (having period TC_INTERVAL at hop counts up to 4, inclusive, property (having period TC_INTERVAL at hop counts up to 4, inclusive,
and 3 x TC_INTERVAL at hop counts greater than 4), but the repeating and 3 x TC_INTERVAL at hop counts greater than 4), but the repeating
pattern (255 255 4 4) does not satisfy this property because at hop pattern (255 255 4 4) does not satisfy this property because at hop
counts greater than 4, message intervals are alternately TC_INTERVAL counts greater than 4, message intervals are alternately TC_INTERVAL
and 3 x TC_INTERVAL. and 3 x TC_INTERVAL.
The following constraints apply to this parameter: The following constraints apply to this parameter:
o The maximum value of TC_HOP_LIMIT >= the network diameter in hops, o The maximum value of TC_HOP_LIMIT >= the network diameter in hops,
a value of 255 is RECOMMENDED. a value of 255 is RECOMMENDED. Note that if using a pattern of
different values of TC_HOP_LIMIT as described above, then only the
maximum value in the patttern is so constrained.
o All values of TC_HOP_LIMIT >= 2. o All values of TC_HOP_LIMIT >= 2.
5.9. Willingness 5.9. Willingness
Each router has a WILLINGNESS parameter, which MUST be in the range Each router has a WILLINGNESS parameter, which MUST be in the range
WILL_NEVER to WILL_ALWAYS, inclusive, and represents its willingness WILL_NEVER to WILL_ALWAYS, inclusive, and represents the router's
to be an MPR, and hence its willingness to forward messages and be an willingness to be an MPR, and hence its willingness to forward
intermediate router on routes. If a router has WILLINGNESS = messages and be an intermediate router on routes. If a router has
WILL_NEVER it does not perform these tasks. A MANET using OLSRv2 WILLINGNESS = WILL_NEVER it does not perform these tasks. A MANET
with too many routers with WILLINGNESS = WILL_NEVER will not using this protocol with too many routers having WILLINGNESS =
function; it MUST be ensured, by administrative or other means, that WILL_NEVER will not function; it MUST be ensured, by administrative
this does not happen. or other means, that this does not happen.
Routers MAY have different WILLINGNESS values; however the three Routers MAY have different WILLINGNESS values; however the three
constants WILL_NEVER, WILL_DEFAULT and WILL_ALWAYS MUST have the constants WILL_NEVER, WILL_DEFAULT and WILL_ALWAYS MUST have the
values defined in Section 17. (Use of WILLINGNESS = WILL_DEFAULT values defined in Section 16. (Use of WILLINGNESS = WILL_DEFAULT
allows a router to avoid including an MPR_WILLING TLV in its TC allows a router to avoid including an MPR_WILLING TLV in its TC
messages, use of WILLINGNESS = WILL_ALWAYS means that a router will messages, use of WILLINGNESS = WILL_ALWAYS means that a router will
always be selected as an MPR by all symmetric 1-hop neighbors.) always be selected as an MPR by all symmetric 1-hop neighbors.)
The following constraints apply to this parameter: The following constraints apply to this parameter:
o WILLINGNESS >= WILL_NEVER o WILLINGNESS >= WILL_NEVER
o WILLINGNESS <= WILL_ALWAYS o WILLINGNESS <= WILL_ALWAYS
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TC_HOP_LIMIT TC_HOP_LIMIT
* If TC_HOP_LIMIT changes, and the router uses multiple values * If TC_HOP_LIMIT changes, and the router uses multiple values
after the change, then message intervals and validity times after the change, then message intervals and validity times
included in TC messages MUST be respected. The simplest way to included in TC messages MUST be respected. The simplest way to
do this is to start any new repeating pattern of TC_HOP_LIMIT do this is to start any new repeating pattern of TC_HOP_LIMIT
values with its largest value. values with its largest value.
6. Information Bases 6. Information Bases
The purpose of OLSRv2 is to determine the Routing Set, which may be The purpose of this protocol is to determine the Routing Set, which
used to update IP's Routing Table, providing "next hop" routing may be used to update IP's Routing Table, providing "next hop"
information for IP datagrams. OLSRv2 maintains the following routing information for IP packets. This specification includes the
Information Bases: following Information Bases:
Local Information Base - as defined in [NHDP], extended by the Local Information Base - as defined in [NHDP], extended by the
addition of an Originator Set, defined in Section 6.1.1 and a inclusion of the router's originator address and the addition of
Local Attached Network Set, defined in Section 6.1.2. an Originator Set, defined in Section 6.1.1, and a Local Attached
Network Set, defined in Section 6.1.2.
Interface Information Bases - as defined in [NHDP], one Interface Interface Information Bases - as defined in [NHDP], an Interface
Information Base for each OLSRv2 interface. Information Base for each OLSRv2 interface.
Neighbor Information Base - as defined in [NHDP], extended by the Neighbor Information Base - as defined in [NHDP], extended by the
addition of three elements to each Neighbor Tuple, as defined in addition of five elements to each Neighbor Tuple, and the
Section 6.2. inclusion of an Advertised Neighbor Sequence Number (ANSN), both
as defined in Section 6.2.
Topology Information Base - this Information Base is specific to Topology Information Base - this Information Base is specific to
OLSRv2, and is defined in Section 6.3. this protocol, and is defined in Section 6.3.
Processing and Forwarding Information Base - this Information Base Received Message Information Base - this Information Base is
is specific to OLSRv2, and is defined in Section 6.4. specific to this protocol, and is defined in Section 6.4.
The ordering of sequence numbers, when considering which is the The ordering of sequence numbers, when considering which is the
greater, is as defined in Section 18. greater, is as defined in Section 17.
6.1. Local Information Base 6.1. Local Information Base
The Local Information Base as defined in [NHDP] is extended by the The Local Information Base as defined in [NHDP] is extended by:
addition of an Originator Set, defined in Section 6.1.1, and a Local
Attached Network Set, defined in Section 6.1.2. o Recording the router's originator address. Note that this MAY be
equal to any address in any I_local_iface_addr_list in a Local
Interface Tuple, but MUST NOT be equal to the AL_net_addr in a
Local Attached Network Tuple.
o The addition of an Originator Set, defined in Section 6.1.1, and a
Local Attached Network Set, defined in Section 6.1.2.
All routable addresses of the router for which it is to accept
packets as destination MUST be included in the Local Interface Set or
the Local Attached Network Set.
6.1.1. Originator Set 6.1.1. Originator Set
A router's Originator Set records addresses that were recently used A router's Originator Set records addresses that were recently used
as originator addresses by this router. If a router's originator as originator addresses by this router. If a router's originator
address is immutable then this set is always empty and MAY be address is immutable then this set is always empty and MAY be
omitted. It consists of Originator Tuples: omitted. It consists of Originator Tuples:
(O_orig_addr, O_time) (O_orig_addr, O_time)
where: where:
O_orig_addr is a recently used originator address; O_orig_addr is a recently used originator address, note that this
does not include a prefix length;
O_time specifies the time at which this Tuple expires and MUST be O_time specifies the time at which this Tuple expires and MUST be
removed. removed.
6.1.2. Local Attached Network Set 6.1.2. Local Attached Network Set
A router's Local Attached Network Set records its local non-OLSRv2 A router's Local Attached Network Set records its local non-OLSRv2
interfaces via which it can act as gateways to other networks. The interfaces via which it can act as gateways to other networks. The
Local Attached Network Set is not modified by this protocol. This Local Attached Network Set is not modified by this protocol. This
protocol MAY respond to changes to the Local Attached Network Set, protocol MAY respond to changes to the Local Attached Network Set,
which MUST reflect corresponding changes in the router's status. It which MUST reflect corresponding changes in the router's status. It
consists of Local Attached Network Tuples: consists of Local Attached Network Tuples:
(AL_net_addr, AL_dist) (AL_net_addr, AL_dist)
where: where:
AL_net_addr is the network address of an attached network which can AL_net_addr is the network address of an attached network which can
be reached via this router. be reached via this router. This SHOULD be a routable address,
and MUST NOT be an interface address, or the originator address,
of this router.
AL_dist is the number of hops to the network with address AL_dist is the number of hops to the network with address
AL_net_addr from this router. AL_net_addr from this router.
Attached networks local to this router SHOULD be treated as local Attached networks local to this router only (i.e. not reachable
non-MANET interfaces, and added to the Local Interface Set, as except via this router) SHOULD be treated as local non-MANET
specified in [NHDP], rather than being added to the Local Attached interfaces, and added to the Local Interface Set, as specified in
Network Set. [NHDP], rather than be added to the Local Attached Network Set.
An attached network MAY also be attached to other routers. Because an attached network is not specific to the router, and may be
outside the MANET, an attached network MAY also be attached to other
routers.
It is not the responsibility of OLSRv2 to maintain routes from this It is not the responsibility of this protocol to maintain routes from
router to networks recorded in the Local Attached Network Set. this router to networks recorded in the Local Attached Network Set.
Local Attached Neighbor Tuples are removed from the Local Attached Local Attached Neighbor Tuples are removed from the Local Attached
Network Set only when the routers' local attached network Network Set only when the routers' local attached network
configuration changes, i.e., they are not subject to timer-based configuration changes, i.e., they are not subject to timer-based
expiration or changes due to received messages. expiration or changes due to received messages.
6.2. Neighbor Information Base 6.2. Neighbor Information Base
Each Neighbor Tuple in the Neighbor Set, defined in [NHDP], has these Each Neighbor Tuple in the Neighbor Set, defined in [NHDP], has these
additional elements: additional elements:
N_willingness is the router's willingness to be selected as an MPR, N_orig_addr is the neighbor's originator address, which may be
in the range from WILL_NEVER to WILL_ALWAYS, both inclusive; unknown. Note that this originator address does not include a
prefix length;
N_willingness is the neighbor's willingness to be selected as an
MPR, in the range from WILL_NEVER to WILL_ALWAYS, both inclusive;
N_mpr is a boolean flag, describing if this neighbor is selected as N_mpr is a boolean flag, describing if this neighbor is selected as
an MPR by this router; an MPR by this router;
N_mpr_selector is a boolean flag, describing if this neighbor has N_mpr_selector is a boolean flag, describing if this neighbor has
selected this router as an MPR, i.e., is an MPR selector of this selected this router as an MPR, i.e., is an MPR selector of this
router. router.
6.3. Topology Information Base N_advertised is a boolean flag, describing if this router has
elected to advertise a link to this neighbor in its TC messages.
The Topology Information Base stores information required for the A Neighbor Tuple created (but not updated) by [NHDP] MUST set:
generation and processing of TC messages, and information received in
TC messages. The Advertised Neighbor Set contains addresses of
symmetric 1-hop neighbors which are to be reported in TC messages.
The Advertising Remote Router Set, the Topology Set and the Attached
Network Set record information received in TC messages.
Additionally, a Routing Set is maintained, derived from the N_orig_addr := unknown;
information recorded in the Neighborhood Information Base, Topology
Set, Attached Network Set and Advertising Remote Router Set.
6.3.1. Advertised Neighbor Set N_willingness := WILL_NEVER;
A router's Advertised Neighbor Set contains addresses of symmetric N_mpr := false;
1-hop neighbors which are to be advertised through TC messages. It
consists of Advertised Neighbor Tuples:
(A_neighbor_addr) N_mpr_selector := false;
In addition, an Advertised Neighbor Set Sequence Number (ANSN) is N_advertised := false.
maintained. Each time the Advertised Neighbor Set is updated, the
ANSN MUST be incremented. The ANSN MUST also be incremented if there
is a change to the set of Local Attached Network Tuples that are to
be advertised in the router's TC messages.
The Advertised Neighbor Set for a router is derived from the Neighbor The Neighbor Information Base also includes a variable, the
Set of that same router, specifically, each address in the Advertised Neighbor Sequence Number (ANSN), whose value is included
N_neighbor_addr_list of a Neighbor Tuple MUST be an A_neighbor_addr in TC messages to indicate the freshness of the information
if the corresponding N_mpr_selector = true, and MAY be an transmitted. The ANSN is incremented whenever advertised information
A_neighbor_addr if the corresponding N_mpr_selector = false. No (the originator and routable addresses included in Neighbor Tuples
other address may be an A_neighbor_addr. The Advertised Neighbor Set with N_advertised = true, and local attached networks recorded in the
MUST therefore be updated when the Neighbor Set changes, see Local Attached Network Set in the Local Information Base) changes.
Section 13. Advertised Neighbor Tuples are not subject to timer-
based expiration.
6.3.2. Advertising Remote Router Set 6.3. Topology Information Base
The Topology Information Base stores information received in TC
messages, in the Advertising Remote Router Set, the Router Topology
Set, the Routable Address Topology Set and the Attached Network Set.
Additionally, a Routing Set is maintained, derived from the
information recorded in the Local Information Base, the Interface
Information Bases, the Neighbor Information Base and the rest of the
Topology Information Base.
6.3.1. Advertising Remote Router Set
A router's Advertising Remote Router Set records information A router's Advertising Remote Router Set records information
describing each remote router in the network that transmits TC describing each remote router in the network that transmits TC
messages. It consists of Advertising Remote Router Tuples: messages, allowing outdated TC messages to be recognized and
discarded. It consists of Advertising Remote Router Tuples:
(AR_orig_addr, AR_seq_number, AR_addr_list, AR_time) (AR_orig_addr, AR_seq_number, AR_time)
where: where:
AR_orig_addr is the originator address of a received TC message, AR_orig_addr is the originator address of a received TC message,
note that this does not include a prefix length; note that this does not include a prefix length;
AR_seq_number is the greatest ANSN in any TC message received which AR_seq_number is the greatest ANSN in any TC message received which
originated from the router with originator address AR_orig_addr originated from the router with originator address AR_orig_addr
(i.e., which contributed to the information contained in this (i.e., which contributed to the information contained in this
Tuple); Tuple);
AR_addr_list is an unordered list of the addresses of the router
with originator address AR_orig_addr;
AR_time is the time at which this Tuple expires and MUST be removed. AR_time is the time at which this Tuple expires and MUST be removed.
6.3.3. Topology Set 6.3.2. Router Topology Set
A router's Topology Set records topology information about the A router's Topology Set records topology information about the links
network. It consists of Topology Tuples: between routers in the MANET, allowing a "backbone" graph of all
routers to be constructed using a minimum distance algorithm. It
consists of Router Topology Tuples:
(T_dest_addr, T_orig_addr, T_seq_number, T_time) (TR_from_orig_addr, TR_to_orig_addr, TR_seq_number, TR_time)
where: where:
T_dest_addr is an address of a destination router, which may be TR_from_orig_addr is the originator address of a router which can
reached in one hop from the router with originator address reach the router with originator address TR_to_orig_addr in one
T_orig_addr; hop, note that this does not include a prefix length;
T_orig_addr is the originator address of a router which is the last TR_to_orig_addr is the originator address of a router which can be
hop on a path towards the router with address T_dest_addr, note reached by the router with originator address TR_to_orig_addr in
that this does not include a prefix length; one hop, note that this does not include a prefix length;
T_seq_number is the greatest ANSN in any TC message received which TR_seq_number is the greatest ANSN in any TC message received which
originated from the router with originator address T_orig_addr originated from the router with originator address
(i.e., which contributed to the information contained in this TR_from_orig_addr (i.e., which contributed to the information
Tuple); contained in this Tuple);
T_time specifies the time at which this Tuple expires and MUST be TR_time specifies the time at which this Tuple expires and MUST be
removed.
6.3.3. Routable Address Topology Set
A router's Routable Address Topology Set records topology information
about the routable addresses within the MANET, and via which routers
they may be reached. It consists of Routable Address Topology
Tuples:
(TA_from_orig_addr, TA_dest_addr, TA_seq_number, TA_time)
where:
TA_from_orig_addr is the originator address of a router which can
reach the router with routable address TA_dest_addr in one hop,
note that this does not include a prefix length;
TA_dest_addr is a routable address of a router which can be reached
by the router with originator address TA_from_orig_addr in one
hop;
TA_seq_number is the greatest ANSN in any TC message received which
originated from the router with originator address
TA_from_orig_addr (i.e., which contributed to the information
contained in this Tuple);
TA_time specifies the time at which this Tuple expires and MUST be
removed. removed.
6.3.4. Attached Network Set 6.3.4. Attached Network Set
A router's Attached Network Set records information about networks A router's Attached Network Set records information about networks
attached to other routers. It consists of Attached Network Tuples: (which may be outside the MANET) attached to other routers and their
routable addresses. It consists of Attached Network Tuples:
(AN_net_addr, AN_orig_addr, AN_dist, AN_seq_number, AN_time) (AN_orig_addr, AN_net_addr, AN_dist, AN_seq_number, AN_time)
where: where:
AN_net_addr is the network address of an attached network, which may
be reached via the router with originator address AN_orig_addr;
AN_orig_addr is the originator address of a router which can act as AN_orig_addr is the originator address of a router which can act as
gateway to the network with address AN_net_addr, note that this gateway to the network with address AN_net_addr, note that this
does not include a prefix length; does not include a prefix length;
AN_net_addr is the network address of an attached network, which may
be reached via the router with originator address AN_orig_addr;
AN_dist is the number of hops to the network with address AN_dist is the number of hops to the network with address
AN_net_addr from the router with originator address AN_orig_addr; AN_net_addr from the router with originator address AN_orig_addr;
AN_seq_number is the greatest ANSN in any TC message received which AN_seq_number is the greatest ANSN in any TC message received which
originated from the router with originator address AN_orig_addr originated from the router with originator address AN_orig_addr
(i.e., which contributed to the information contained in this (i.e., which contributed to the information contained in this
Tuple); Tuple);
AN_time specifies the time at which this Tuple expires and MUST be AN_time specifies the time at which this Tuple expires and MUST be
removed. removed.
6.3.5. Routing Set 6.3.5. Routing Set
A router's Routing Set records the selected path to each destination A router's Routing Set records the first hop along a selected path to
for which a route is known. It consists of Routing Tuples: each destination for which any such path is known. It consists of
Routing Tuples:
(R_dest_addr, R_next_iface_addr, R_dist, R_local_iface_addr) (R_dest_addr, R_next_iface_addr, R_local_iface_addr, R_dist)
where: where:
R_dest_addr is the address of the destination, either the address of R_dest_addr is the address of the destination, either the address of
an interface of a destination router, or the network address of an an interface of a destination router, or the network address of an
attached network; attached network;
R_next_iface_addr is the address of the "next hop" on the selected R_next_iface_addr is the address of the "next hop" on the selected
path to the destination; path to the destination;
R_dist is the number of hops on the selected path to the
destination;
R_local_iface_addr is the address of the local OLSRv2 interface over R_local_iface_addr is the address of the local OLSRv2 interface over
which a packet MUST be sent to reach the destination by the which a packet MUST be sent to reach the destination by the
selected path. selected path.
The Routing Set for a router is derived from the contents of the R_dist is the number of hops on the selected path to the
other sets of the router, and is updated (Routing Tuples added or destination;
removed) when routing paths are calculated. Routing Tuples are not
subject to timer-based expiration.
6.4. Processing and Forwarding Information Base The Routing Set for a router is derived from the contents of other
protocol Sets of the router (the Link Sets, the Neighbor Set, the
Router Topology Set, the Routable Address Topology Set, the Attached
Network Set, and OPTIONALLY the Two Hop Sets). The Routing Set is
updated (Routing Tuples added or removed, or the complete Routing Set
recalculated) when routing paths are calculated, based on changes to
these other protocol Sets. Routing Tuples are not subject to timer-
based expiration.
The Processing and Forwarding Information Base records information 6.4. Received Message Information Base
required to ensure that a message is processed at most once and is
forwarded at most once per OLSRv2 interface of a router, using MPR The Received Message Information Base records information required to
flooding. ensure that a message is processed at most once and is forwarded at
most once per OLSRv2 interface of a router, using MPR flooding.
6.4.1. Received Set 6.4.1. Received Set
A router has a Received Set per local OLSRv2 interface. Each A router has a Received Set per OLSRv2 interface. Each Received Set
Received Set records the signatures of messages which have been records the signatures of messages which have been received over that
received over that OLSRv2 interface. Each consists of Received OLSRv2 interface. Each consists of Received Tuples:
Tuples:
(RX_type, RX_orig_addr, RX_seq_number, RX_time) (RX_type, RX_orig_addr, RX_seq_number, RX_time)
where: where:
RX_type is the received Message Type; RX_type is the received Message Type;
RX_orig_addr is the originator address of the received message; RX_orig_addr is the originator address of the received message, note
that this does not include a prefix length;
RX_seq_number is the message sequence number of the received RX_seq_number is the message sequence number of the received
message; message;
RX_time specifies the time at which this Tuple expires and MUST be RX_time specifies the time at which this Tuple expires and MUST be
removed. removed.
6.4.2. Processed Set 6.4.2. Processed Set
A router's Processed Set records signatures of messages which have A router has a single Processed Set which records signatures of
been processed by the router. It consists of Processed Tuples: messages which have been processed by the router. It consists of
Processed Tuples:
(P_type, P_orig_addr, P_seq_number, P_time) (P_type, P_orig_addr, P_seq_number, P_time)
where: where:
P_type is the processed Message Type; P_type is the processed Message Type;
P_orig_addr is the originator address of the processed message; P_orig_addr is the originator address of the processed message, note
that this does not include a prefix length;
P_seq_number is the message sequence number of the processed P_seq_number is the message sequence number of the processed
message; message;
P_time specifies the time at which this Tuple expires and MUST be P_time specifies the time at which this Tuple expires and MUST be
removed. removed.
6.4.3. Forwarded Set 6.4.3. Forwarded Set
A router's Forwarded Set records signatures of messages which have A router has a single Forwarded Set which records signatures of
been processed by the router. It consists of Forwarded Tuples: messages which have been forwarded by the router. It consists of
Forwarded Tuples:
(F_type, F_orig_addr, F_seq_number, F_time) (F_type, F_orig_addr, F_seq_number, F_time)
where: where:
F_type is the forwarded Message Type; F_type is the forwarded Message Type;
F_orig_addr is the originator address of the forwarded message; F_orig_addr is the originator address of the forwarded message, note
that this does not include a prefix length;
F_seq_number is the message sequence number of the forwarded F_seq_number is the message sequence number of the forwarded
message; message;
F_time specifies the time at which this Tuple expires and MUST be F_time specifies the time at which this Tuple expires and MUST be
removed. removed.
6.4.4. Relay Set 6.5. Corresponding Protocol Tuples
A router has a Relay Set per local OLSRv2 interface. Each Relay Set In a number of cases there is a natural correspondence from a
records the addresses of symmetric 1-hop neighbors, such that the Protocol Tuple in a Protocol Set to a single Protocol Tuple in
router is to forward messages received from those neighbors' OLSRv2 another Protocol Set. The latter Protocol Tuple is referred to as
interfaces, on that local OLSRv2 interface, if not otherwise excluded "corresponding" to the former.
from forwarding that message (e.g., by it having been previously
forwarded). It consists of Relay Tuples:
(RY_neighbor_iface_addr) Specific examples include:
The Relay Set for an interface is derived from the Link Set for the o There is a Local Interface Tuple corresponding to each Link Tuple,
same interface, and so Relay Tuples are removed when the where the Link Tuple is in the Link Set for an OLSRv2 interface,
corresponding Link Tuples in the Link Set of this interface are and the Local Interface Tuple represents that OLSRv2 interface.
removed, or when processing otherwise suggests their removal. Relay
Tuples are not subject to timer-based expiration. o There is a Neighbor Tuple corresponding to each Link Tuple which
has L_HEARD_time not expired, such that N_neighbor_addr_list
contains L_neighbor_iface_addr_list.
o There is a Link Tuple (in the Link Set in the same Interface
Information Base) corresponding to each 2-Hop Tuple such that
L_neighbor_iface_addr_list = N2_neighbor_iface_addr_list.
o There is a Neighbor Tuple corresponding to each 2-Hop Tuple, such
that N_neighbor_addr_list contains N2_neighbor_iface_addr_list.
o There is an Advertising Remote Router Tuple corresponding to each
Router Topology Tuple such that AR_orig_addr = TR_from_orig_addr.
o There is an Advertising Remote Router Tuple corresponding to each
Routable Address Topology Tuple such that AR_orig_addr =
TA_from_orig_addr.
o There is an Advertising Remote Router Tuple corresponding to each
Attached Network Tuple such that AR_orig_addr = AN_orig_addr.
o There is an Neighbor Tuple corresponding to each Routing Tuple
such that N_neighbor_addr_list contains R_next_iface_addr.
7. Message Processing and Forwarding 7. Message Processing and Forwarding
On receiving a packet, as defined in [RFC5444], a router divides the This protocol defines, and hence owns, the TC message type (see
packet into the Packet Header and messages. OLSRv2 defines, and Section 20). Thus, as specified in [RFC5444], this protocol receives
hence owns, the TC Message Type, and hence receives all TC messages. all TC messages and is responsible for determining whether and how
OLSRv2 is responsible for determining whether a TC message is to be each TC message is to be processed (updating Information Bases)
processed (updating Information Bases) and/or forwarded. and/or forwarded, according to this specification. OLSRv2 does not
require any part of the Packet Header.
OLSRv2 also receives HELLO messages, which are defined, and hence This protocol also receives HELLO messages, which are defined, and
owned, by [NHDP]. Received HELLO messages MUST be made available to hence owned, by [NHDP]. Such messages, when received on an OLSRv2
OLSRv2 when received on an OLSRv2 interface and after NHDP has interface, are made available to this protocol in two ways, both as
completed its processing thereof. OLSRv2 also processes HELLO permitted by [NHDP]. First, such received HELLO messages MUST be
messages, OLSRv2 does not forward HELLO messages. made available to this protocol on reception, which allows them to be
discarded before being processed by [NHDP], for example if the
information added to the HELLO message by this protocol is
inconsistent. Second, such received HELLO messages MUST be made
available to OLSRv2 after [NHDP] has completed its processing
thereof, unless discarded as malformed by [NHDP], for processing by
this protocol. HELLO messages are not forwarded by this protocol.
Extensions to OLSRv2 which define, and hence own, other Messages Extensions to this protocol which define, and hence own, other
Types, MAY manage the processing and/or forwarding of these messages Messages Types, MAY manage the processing and/or forwarding of these
using the same mechanism as for TC messages. These mechanisms messages using the same mechanism as for TC messages. These
contain elements (P_type, RX_type, F_type) required only for such mechanisms contain elements (P_type, RX_type, F_type) required only
usage. for such usage.
The processing selection and forwarding mechanisms are designed to The processing selection and forwarding mechanisms are designed to
only need to parse the Message Header in order to determine whether a only need to parse the Message Header in order to determine whether a
message is to be processed and/or forwarded, and not to have to parse message is to be processed and/or forwarded, and not to have to parse
the Message Body even if the message is forwarded (but not the Message Body even if the message is forwarded (but not
processed). An implementation MAY either only parse the Message Body processed). An implementation MAY either only parse the Message Body
if necessary, or MAY always parse the Message Body. An if necessary, or MAY always parse the Message Body.
implementation MUST discard the message silently if it is unable to
parse the Message Header or (if attempted) the Message Body.
OLSRv2 does not require any part of the Packet Header. An implementation MUST discard the message silently if it is unable
to parse the Message Header or (if attempted) the Message Body.
7.1. Actions when Receiving a Message 7.1. Actions when Receiving a Message
If the router receives a HELLO message from [NHDP], then the message If the router receives a HELLO message from [NHDP], then the message
is processed according to Section 10. may be rejected before processing by [NHDP] or processed after
processing by [NHDP], both according to Section 10.
A router MUST perform the following tasks for each received TC A router MUST perform the following tasks for each received TC
message or other Message Type defined by an extension to OLSRv2 and message (or other Message Type defined by an extension to this
specified to use this process: protocol and specified to use this process):
1. If the router recognizes from the originator address of the 1. If the router recognizes from the originator address of the
message that the message is one which the receiving router itself message that the message is one which the receiving router itself
originated (i.e. is the current originator address of the router, originated (i.e. is the originator address of this router, or is
or is an O_orig_addr in an Originator Tuple) then the message an O_orig_addr in an Originator Tuple) then the message MUST be
MUST be silently discarded. silently discarded.
2. Otherwise: 2. Otherwise:
1. Otherwise: 1. If the message is of a type which may be processed, including
being a TC message, then the message is considered for
1. If the message is of a type which may be processed, processing according to Section 7.2, AND;
including being a TC message, then the message is
considered for processing according to Section 7.2, AND;
2. If for the message is of a type which may be forwarded, 2. If the message is of a type which may be forwarded, including
including being a TC message, AND: being a TC message, AND:
- <msg-hop-limit> is present and <msg-hop-limit> > 1, + <msg-hop-limit> is present and <msg-hop-limit> > 1, AND;
AND;
- <msg-hop-count> is not present or <msg-hop-count> < + <msg-hop-count> is not present or <msg-hop-count> < 255
255
then the message is considered for forwarding according then the message is considered for forwarding according to
to Section 7.3. Section 7.3.
7.2. Message Considered for Processing 7.2. Message Considered for Processing
If a message (the "current message") is considered for processing, If a message (the "current message") is considered for processing,
then the following tasks MUST be performed: then the following tasks MUST be performed:
1. If a Processed Tuple exists with: 1. If a Processed Tuple exists with:
* P_type = the Message Type of the current message, AND; * P_type = the Message Type of the current message, AND;
skipping to change at page 30, line 35 skipping to change at page 34, line 31
- F_orig_addr = the originator address of the current - F_orig_addr = the originator address of the current
message, AND; message, AND;
- F_seq_number = the sequence number of the current - F_seq_number = the sequence number of the current
message. message.
then the current message MUST be silently discarded. then the current message MUST be silently discarded.
3. Otherwise if the sending address matches (taking account 3. Otherwise if the sending address matches (taking account
of any address prefix) an RY_neighbor_iface_addr in the of any address prefix) any address in an
Relay Set for the receiving interface, then: L_neighbor_iface_addr_list of a Link Tuple in the Link
Set for the receiving OLSRv2 interface which has L_status
= SYMMETRIC and whose corresponding Neighbor Tuple has
N_mpr_selector = true, then:
1. Create a Forwarded Tuple with: 1. Create a Forwarded Tuple with:
o F_type := the Message Type of the current message; o F_type := the Message Type of the current message;
o F_orig_addr := originator address of the current o F_orig_addr := originator address of the current
message; message;
o F_seq_number := sequence number of the current o F_seq_number := sequence number of the current
message; message;
skipping to change at page 31, line 29 skipping to change at page 35, line 29
be based on information in that message (in be based on information in that message (in
particular any INTERVAL_TIME or VALIDITY_TIME TLVs in particular any INTERVAL_TIME or VALIDITY_TIME TLVs in
that message) or otherwise SHOULD be with a maximum that message) or otherwise SHOULD be with a maximum
delay of F_MAXJITTER. A router MAY modify the jitter delay of F_MAXJITTER. A router MAY modify the jitter
applied to a message in order to more efficiently applied to a message in order to more efficiently
combine messages in packets, as long as the maximum combine messages in packets, as long as the maximum
jitter is not exceeded. jitter is not exceeded.
8. Packets and Messages 8. Packets and Messages
The packet and message format used by OLSRv2 is defined in [RFC5444]. The packet and message format used by this protocol is defined in
Except as otherwise noted, options defined in [RFC5444] may be freely [RFC5444]. Except as otherwise noted, options defined in [RFC5444]
used, in particular alternative formats defined by packet, message, may be freely used, in particular alternative formats defined by
Address Block and TLV flags. packet, message, Address Block and TLV flags.
OLSRv2 defines and owns the TC Message Type. OLSRv2 also modifies This protocol may extend HELLO messages (owned by [NHDP]) by adding a
HELLO messages (owned by [NHDP]) by adding TLVs to these messages message originator address and/or TLVs to these messages when sent
when sent over OLSRv2 interfaces, and processes these HELLO messages, over OLSRv2 interfaces, and processes these HELLO messages after
subsequent to their processing by NHDP. Extensions to OLSRv2 MAY their processing by NHDP, as permitted by [NHDP].
define additional Message Types to be handled similarly to TC
messages.
Routers using OLSRv2 exchange information through messages. One or This protocol defines and owns the TC Message Type. Extensions to
more messages sent by a router at the same time SHOULD be combined this protocol MAY define additions to TC messages. These MAY include
into a single packet. These messages may have originated at the new Message TLVs and/or Address Block TLVs. Extensions MAY also
sending router, or have originated at another router and are include new Messsage Types to be handled similarly to TC messages.
forwarded by the sending router. Messages with different originating See Section 18.
routers MAY be combined for transmission within the same packet.
Messages from other protocols defined using [RFC5444] MAY be combined Routers using this protocol exchange information through messages.
for transmission within the same packet. One or more messages sent by a router at the same time SHOULD be
combined into a single packet (size permitting). These messages may
have originated at the sending router, or have originated at another
router and are forwarded by the sending router. Messages with
different originating routers MAY be combined for transmission within
the same packet. Messages from other protocols defined using
[RFC5444] MAY be combined for transmission within the same packet.
The remainder of this section defines, within the framework of The remainder of this section defines, within the framework of
[RFC5444], Message Types and TLVs specific to OLSRv2. All references [RFC5444], Message Types and TLVs specific to this protocol. All
in this specification to TLVs that do not indicate a type extension, references in this specification to TLVs that do not indicate a type
assume Type Extension = 0. TLVs in processed messages with a type extension, assume Type Extension = 0. TLVs in processed messages
extension which is neither zero as so assumed, nor a specifically with a type extension which is neither zero as so assumed, nor a
indicated non-zero type extension, are ignored. specifically indicated non-zero type extension, are ignored.
8.1. HELLO Messages 8.1. HELLO Messages
A HELLO message in OLSRv2 is generated as specified in [NHDP]. In A HELLO message is generated as specified in [NHDP]. In addition, a
addition, an OLSRv2 router MUST be able to modify such messages, router using this protocol MUST be able to add information to such
prior to these being sent on an OLSRv2 interface, so that such HELLO messages, prior to these being sent on an OLSRv2 interface, as
messages: permitted by [NHDP], so that all HELLO messages sent on an OLSRv2
interface:
o MUST include TLV(s) with Type := MPR associated with all addresses o MUST allow a message originator address to be determined. This
that: will usually use the message's <msg-orig-addr> element as defined
in [RFC5444]. There are two permitted exceptions when the router
MAY omit a <msg-orig-addr> element, but an originator address of
the message is still correctly defined:
* are included in the HELLO message associated with a TLV with * If the message contains only a single local interface address,
Type = LINK_STATUS and Value = SYMMETRIC; AND and that address is equal to this router's originator address,
then that local interface address is the message originator
address.
* are included in a Neighbor Tuple with N_mpr = true. * If the message contains no local interface addresses, then, as
specified in [NHDP], the source address of the IP datagram
containing the message is recognised as the only interface
address of the router. In this case, that address is also the
message originator address.
o MUST, if it is including any addresses from an
N_neighbor_addr_list that has N_mpr = true and are associated with
a TLV with Type = LINK_STATUS and Value = SYMMETRIC, include
TLV(s) with Type := MPR associated with at least one such address
from each such N_neighbor_addr_list.
o MUST NOT include any TLVs with Type = MPR associated with any o MUST NOT include any TLVs with Type = MPR associated with any
other addresses. other addresses.
o MAY include a message TLV with Type := MPR_WILLING, indicating the o MAY include a message TLV with Type := MPR_WILLING, indicating the
router's willingness to be selected as an MPR. router's willingness to be selected as an MPR.
An OLSRv2 router MUST also be able to process any HELLO message An router using this protocol MUST also be able to access any
received on an OLSRv2 interface, subsequent to the processing incoming HELLO message received on an OLSRv2 interface, subsequent to
specified in [NHDP]. the processing specified in [NHDP], as permitted by [NHDP].
8.1.1. HELLO Message TLVs 8.1.1. HELLO Message TLVs
In a HELLO message, a router MUST include an MPR_WILLING Message TLV In a HELLO message, a router MUST include an MPR_WILLING Message TLV
as specified in Table 1, unless WILLINGNESS = WILL_DEFAULT (in which as specified in Table 1, unless WILLINGNESS = WILL_DEFAULT (in which
case it MAY be included). A router MUST NOT include more than one case it MAY be included). A router MUST NOT include more than one
MPR_WILLING Message TLV. MPR_WILLING Message TLV.
+-------------+--------------+--------------------------------------+ +-------------+--------------+--------------------------------------+
| Type | Value Length | Value | | Type | Value Length | Value |
+-------------+--------------+--------------------------------------+ +-------------+--------------+--------------------------------------+
| MPR_WILLING | 1 octet | Router parameter WILLINGNESS; unused | | MPR_WILLING | 1 octet | Router parameter WILLINGNESS; unused |
| | | bits (based on the maximum | | | | bits (based on the maximum |
| | | willingness value WILL_ALWAYS) are | | | | willingness value WILL_ALWAYS) are |
| | | RESERVED and SHOULD be set to zero. | | | | RESERVED and SHOULD be set to zero. |
+-------------+--------------+--------------------------------------+ +-------------+--------------+--------------------------------------+
Table 1 Table 1: MPR_WILLING TLV definition
If a router does not advertise an MPR_WILLING TLV in a HELLO message, If a router does not advertise an MPR_WILLING TLV in a HELLO message,
then the router MUST be assumed to have WILLINGNESS equal to then the router MUST be assumed to have WILLINGNESS equal to
WILL_DEFAULT. WILL_DEFAULT.
8.1.2. HELLO Message Address Block TLVs 8.1.2. HELLO Message Address Block TLVs
In a HELLO message, a router MAY include MPR Address Block TLV(s) as In a HELLO message, a router MAY include MPR Address Block TLV(s) as
specified in Table 2. specified in Table 2.
+------+--------------+-------+ +------+--------------+-------+
| Type | Value Length | Value | | Type | Value Length | Value |
+------+--------------+-------+ +------+--------------+-------+
| MPR | 0 octets | None. | | MPR | 0 octets | None. |
+------+--------------+-------+ +------+--------------+-------+
Table 2 Table 2: MPR TLV definition
8.2. TC Messages 8.2. TC Messages
A TC message MUST contain: A TC message MUST contain:
o <msg-orig-addr>, <msg-seq-num> and <msg-hop-limit> elements in its o A message originator address, using the message's <msg-orig-addr>
Message Header, as specified in [RFC5444]. element as defined in [RFC5444].
o <msg-seq-num> and <msg-hop-limit> elements, as specified in
[RFC5444].
o A <msg-hop-count> element in its Message Header if the message o A <msg-hop-count> element in its Message Header if the message
contains a TLV with either Type = VALIDITY_TIME or Type = contains a TLV with either Type = VALIDITY_TIME or Type =
INTERVAL_TIME indicating more than one time value according to INTERVAL_TIME indicating more than one time value according to
distance. (A TC message MAY contain <msg-hop-count> even if it distance. (A TC message MAY contain <msg-hop-count> even if it
does not need to.) does not need to.)
o A single Message TLV with Type := CONT_SEQ_NUM, and Type Extension o A single Message TLV with Type := CONT_SEQ_NUM, and Type Extension
:= COMPLETE or Type Extension := INCOMPLETE, as specified in := COMPLETE or Type Extension := INCOMPLETE, as specified in
Section 8.2.1 (for complete and incomplete TC messages, Section 8.2.1 (for complete and incomplete TC messages,
respectively). respectively) except that the latter MAY be omitted if the message
does not contain any addresses associated with a TLV with Type =
NBR_ADDR_TYPE or Type = GATEWAY.
o A Message TLV with Type := VALIDITY_TIME, as specified in o A Message TLV with Type := VALIDITY_TIME, as specified in
[RFC5497]. The options included in [RFC5497] for representing [RFC5497]. The options included in [RFC5497] for representing
zero and infinite times MUST NOT be used. zero and infinite times MUST NOT be used.
o All of the router's addresses. These MUST be included in the o If the TC message is complete, all addresses which are the
message's Address Blocks, unless: N_orig_addr of a Neighbor Tuple with N_advertised = true, each
associated with a TLV with Type = NBR_ADDR_TYPE, and Value =
* the router has a single interface, with a single address with ORIGINATOR, or with Value = ROUTABLE_ORIG if also to be associated
maximum prefix length; AND with Value = ROUTABLE, see Section 8.2.2. If the TC message is
incomplete then any such addresses MAY be included; if any such
* that address is the router's originator address. addresses are included then this MUST be with the appropriate
associated TLV(s).
In this exceptional case, the address will be included as the
message's originator address, and MAY be omitted from the
message's Address Blocks.
o TLV(s) with Type := LOCAL_IF and Value := UNSPEC_IF associated o If the TC message is complete, all routable addresses which are in
with all of the router's addresses. the N_neighbor_addr_list of a Neighbor Tuple with N_advertised =
true. Each such address MUST be associated with a TLV with Type =
NBR_ADDR_TYPE, and Value = ROUTABLE, or with Value = ROUTABLE_ORIG
if also to be associated with Value = ORIGINATOR, see
Section 8.2.2. If the TC message is incomplete then any such
addresses MAY be included; if any such addresses are included then
this MUST be with the appropriate associated TLV(s).
o If the TC message is complete, all addresses in the Advertised o If the TC message is complete, all addresses which are the
Address Set and all addresses in the Local Attached Network Set, AL_net_addr of a Local Attached Network Tuple. Each such address
the latter (only) with associated GATEWAY Address Block TLV(s), as MUST be associated with a TLV with Type = GATEWAY, and Value =
specified in Section 8.2.2. AN_dist as specified in Section 8.2.2. If the TC message is
incomplete then any such addresses MAY be included; if included
then this MUST be with the appropriate associated TLV.
A TC message MAY contain: A TC message MAY contain:
o If the TC message is incomplete, any addresses in the Advertised
Address Set and any addresses in the Local Attached Network Set,
the latter (only) with associated GATEWAY Address Block TLV(s), as
specified in Section 8.2.2.
o A Message TLV with Type := INTERVAL_TIME, as specified in o A Message TLV with Type := INTERVAL_TIME, as specified in
[RFC5497]. The options included in [RFC5497] for representing [RFC5497]. The options included in [RFC5497] for representing
zero and infinite times MUST NOT be used. zero and infinite times MUST NOT be used.
8.2.1. TC Message TLVs 8.2.1. TC Message TLVs
In a TC message, a router MUST include a single CONT_SEQ_NUM Message In each TC message which contains any addresses associated with a TLV
TLV, as specified in Table 3, and with Type Extension = COMPLETE or with Type = NBR_ADDR_TYPE or Type = GATEWAY, a router MUST include a
Type Extension = INCOMPLETE, according to whether the TC message is single CONT_SEQ_NUM Message TLV, as specified in Table 3, and with
complete or incomplete. Type Extension = COMPLETE or Type Extension = INCOMPLETE, according
to whether the TC message is complete or incomplete.
+--------------+--------------+-------------------------------------+ +--------------+--------------+-------------------------------------+
| Type | Value Length | Value | | Type | Value Length | Value |
+--------------+--------------+-------------------------------------+ +--------------+--------------+-------------------------------------+
| CONT_SEQ_NUM | 2 octets | The ANSN contained in the | | CONT_SEQ_NUM | 2 octets | The ANSN contained in the Neighbor |
| | | Advertised Neighbor Set. | | | | Information Base. |
+--------------+--------------+-------------------------------------+ +--------------+--------------+-------------------------------------+
Table 3 Table 3: CONT_SEQ_NUM TLV definition
8.2.2. TC Message Address Block TLVs 8.2.2. TC Message Address Block TLVs
In a TC message, a router MAY include NBR_ADDR_TYPE Address Block
TLV(s) as specified in Table 4.
+---------------+--------------+------------------------------------+
| Type | Value Length | Value |
+---------------+--------------+------------------------------------+
| NBR_ADDR_TYPE | 1 octet | ORIGINATOR indicates that the |
| | | address is an originator address, |
| | | ROUTABLE indicates that the |
| | | address is a routable address of |
| | | an interface, ROUTABLE_ORIG |
| | | indicates that the address is both |
+---------------+--------------+------------------------------------+
Table 4: NBR_ADDR_TYPE TLV definition
If an address is both a originator address and a routable interface
address, then it may be associated, using a TLV with Type =
NBR_ADDR_TYPE, with either a Value = ROUTABLE_ORIG, or (using two
separate TLVs) both with Value = ORIGINATOR and with Value =
ROUTABLE.
In a TC message, a router MAY include GATEWAY Address Block TLV(s) as In a TC message, a router MAY include GATEWAY Address Block TLV(s) as
specified in Table 4. specified in Table 5.
+---------+--------------+-------------------------------------+ +---------+--------------+-------------------------------------+
| Type | Value Length | Value | | Type | Value Length | Value |
+---------+--------------+-------------------------------------+ +---------+--------------+-------------------------------------+
| GATEWAY | 1 octet | Number of hops to attached network. | | GATEWAY | 1 octet | Number of hops to attached network. |
+---------+--------------+-------------------------------------+ +---------+--------------+-------------------------------------+
Table 4 Table 5
GATEWAY Address Block TLV(s) MUST be associated with all attached All addresses included in a TC message according to this
network addresses, and MUST NOT be associated with any other specification MUST be associated with either at least one TLV with
addresses. Type = NBR_ADDR_TYPE or a TLV with Type = GATEWAY, but not both.
Other addresses MAY be included in the TC message, but (other than
the message originator address) are ignored by this specification.
9. HELLO Message Generation 9. HELLO Message Generation
An OLSRv2 HELLO message is composed and generated as defined in An HELLO message is composed and generated as defined in [NHDP],
[NHDP], with the following additions: extended by the following being added to the HELLO message by this
protocol before being sent over an OLSRv2 interface, as permitted by
[NHDP]:
o A message originator address, using a <msg-orig-addr> element,
unless:
* The message contains only a single local interface address,
which is then interpreted as the message originator address,
OR;
* The message does not include any local interface addresses, as
permitted by the specification in [NHDP] when the router that
generated the HELLO message has only one interface address, and
will use that as the sending address of the IP datagram in
which the HELLO message is contained. In this case that
address MAY also be used as the message originator address.
o A Message TLV with Type := MPR_WILLING and Value := WILLINGNESS o A Message TLV with Type := MPR_WILLING and Value := WILLINGNESS
MUST be included, unless WILLINGNESS = WILL_DEFAULT (in which case MUST be included, unless WILLINGNESS = WILL_DEFAULT (in which case
it MAY be included). it MAY be included).
o For each address which is included in the message with an o For each Neighbor Tuple with N_mpr = true, and for which one or
associated TLV with Type = LINK_STATUS and Value = SYMMETRIC, and more addresses in its N_neighbor_addr_list are included with an
is of an MPR (i.e. the address is in the N_neighbor_addr_list of a associated TLV with Type = LINK_STATUS and Value = SYMMETRIC, at
Neighbor Tuple with N_mpr = true), that address (including a least one of these addresses (including a different copy of that
different copy of that address, in the same or a different Address address, in the same or a different Address Block) MUST be
Block) MUST be associated with an Address Block TLV with Type := associated with an Address Block TLV with Type := MPR. Note that
MPR. other addresses (which do not meet this specification) MUST NOT be
associated with an Address Block TLV with Type = MPR, but that
o For each address which is included in the message and is not more than one address from the same qualifying
associated with a TLV with Type = LINK_STATUS and Value = N_neighbor_addr_list MAY be associated with an Address Block TLV
SYMMETRIC, or is not of an MPR (i.e. the address is not in the with Type := MPR.
N_neighbor_addr_list of a Neighbor Tuple with N_mpr = true), that
address (including different copies of that address, in the same
or different Address Blocks) MUST NOT be associated with an
Address Block TLV with Type := MPR.
o An additional HELLO message MAY be sent when the router's set of o An additional HELLO message MAY be sent when the router's set of
MPRs changes, in addition to the cases specified in [NHDP], and MPRs changes, in addition to the cases specified in [NHDP], and
subject to the same constraints. subject to the same constraints.
9.1. HELLO Message: Transmission 9.1. HELLO Message: Transmission
HELLO messages are included in packets as specified in [RFC5444]. HELLO messages are included in packets as specified in [RFC5444].
These packets may contain other messages, including TC messages. These packets may contain other messages, including TC messages.
10. HELLO Message Processing 10. HELLO Message Processing
All HELLO message processing, including determination of whether a All HELLO message processing, including determination of whether a
message is invalid, considers only TLVs with Type Extension = 0. message is invalid, considers only TLVs with Type Extension = 0.
TLVs with any other type extension are ignored. All references to, TLVs with any other type extension are ignored. All references to,
for example, a TLV with Type = MPR_WILLING refer to a TLV with Type = for example, a TLV with Type = MPR_WILLING refer to a TLV with Type =
MPR_WILLING and Type Extension = 0. MPR_WILLING and Type Extension = 0.
In addition to the reasons specified in [NHDP], for discarding a In addition to the reasons specified in [NHDP] for discarding a HELLO
HELLO message on reception, a HELLO message MUST NOT: message on reception, a HELLO message MUST be discarded before
processing by [NHDP] or this specification if it:
o Have more than one TLV with Type = MPR_WILLING in its Message TLV o Has more than one TLV with Type = MPR_WILLING in its Message TLV
Block, where TLVs have different Values. Block.
o Contain any address associated with a TLV with Type = MPR, where o Has a message originator address, or any address associated with a
that address (including a different copy of that address, in the TLV with Type = LOCAL_IF, that the receiving router has recorded
same or a different Address Block) which is not also associated as:
with the single Value SYMMETRIC by a TLV with Type = LINK_STATUS
or Type = OTHER_NEIGHB.
Such a HELLO message MAY be discarded before processing. If it is * its originator address, OR;
not then all TLVs with the type(s) for which an error was indicated
MUST be ignored (treated as not present) in the following processing.
HELLO messages are first processed as specified in [NHDP]. The * as the O_orig_addr in an Originator Tuple, OR;
router MUST identify the Neighbor Tuple corresponding to the
originator of the HELLO message (the "current Neighbor Tuple") and
update its N_willingness as described in Section 10.1 and its
N_mpr_selector as described in Section 10.2. Following these, the
router MUST also perform the processing defined in Section 10.3.
10.1. Updating Willingness * in an I_local_iface_addr_list in a Local Interface Tuple, OR;
N_willingness in the current Neighbor Tuple is updated as follows: * as the IR_local_iface_addr in a Removed Interface Address
Tuple, OR;
1. If the HELLO message contains a Message TLV with Type = * as the AL_net_addr in a Local Attached Network Tuple.
MPR_WILLING then N_willingness := the Value of that TLV;
2. Otherwise, N_willingness := WILL_DEFAULT. Note that some of these cases are already excluded by [NHDP].
10.2. Updating MPR Selectors o Includes any address associated with a TLV with Type = LINK_STATUS
or Type = OTHER_NEIGHB that is also the message's originator
address.
N_mpr_selector is updated as follows: o Contains any address associated with a TLV with Type = MPR, where
that address (including a different copy of that address, in the
same or a different Address Block) is not also associated with a
TLV with Type = LINK_STATUS and Value = SYMMETRIC.
1. If a router finds any of its local addresses with an associated HELLO messages are first processed as specified in [NHDP]. That
TLV with Type = MPR in the HELLO message (indicating that the processing includes identifying (or creating) a Neighbor Tuple
originator router has selected the receiving router as an MPR) corresponding to the originator of the HELLO message (the "current
then, for the current Neighbor Tuple: Neighbor Tuple"). After this, the following MUST be performed:
* N_mpr_selector := true 1. If the HELLO message has a well-defined message originator
address, i.e., has an <msg-orig-addr> element or has zero or one
addresses associated with a TLV with Type = LOCAL_IF:
2. Otherwise, if a router finds any of its own addresses with an 1. Remove any other Neighbor Tuples with N_orig_addr = message
associated TLV with Type = LINK_STATUS and Value = SYMMETRIC in originator address, taking any consequent action (including
the HELLO message, then for the current Neighbor Tuple: removing one or more Link Tuples) as specified in [NHDP].
* N_mpr_selector := false 2. The current Neighbor Tuple is then updated according to:
10.3. Symmetric 1-Hop and 2-Hop Neighborhood Changes 1. N_orig_addr := message originator address;
A router MUST also perform the following: 2. Update N_willingness as described in Section 10.1;
1. If N_symmetric of a Neighbor Tuple changes from true to false, 3. Update N_mpr_selector as described in Section 10.2.
for that Neighbor Tuple:
* N_mpr_selector := false 2. If there are any changes to the router's Information Bases, then
perform the processing defined in Section 13.
2. The set of MPRs of a router MUST be recalculated if: 10.1. Updating Willingness
* a Link Tuple is added with L_status = SYMMETRIC, OR; N_willingness in the current Neighbor Tuple is updated as follows:
* a Link Tuple with L_status = SYMMETRIC is removed, OR; 1. If the HELLO message contains a Message TLV with Type =
MPR_WILLING then N_willingness := the Value of that TLV;
* a Link Tuple with L_status = SYMMETRIC changes to having 2. Otherwise, N_willingness := WILL_DEFAULT.
L_status = HEARD or L_status = LOST, OR;
* a Link Tuple with L_status = HEARD or L_status = LOST changes 10.2. Updating MPR Selectors
to having L_status = SYMMETRIC, OR;
* a 2-Hop Tuple is added or removed, OR; N_mpr_selector is updated as follows:
* the N_willingness of a Neighbor Tuple with N_symmetric = true 1. If a router finds any of its local interface addresses (i.e.,
changes from WILL_NEVER to any other value, OR; those contained in the I_local_iface_addr_list of an OLSRv2
interface) with an associated TLV with Type = MPR in the HELLO
message (indicating that the originating router has selected the
receiving router as an MPR) then, for the current Neighbor Tuple:
* the N_willingness of a Neighbor Tuple with N_symmetric = true * N_mpr_selector := true
and N_mpr = true changes to WILL_NEVER from any other value,
OR;
* the N_willingness of a Neighbor Tuple with N_symmetric = true 2. Otherwise (i.e., if no such address and TLV were found) if a
and N_mpr = false changes to WILL_ALWAYS from any other value. router finds any of its local interface addresses with an
associated TLV with Type = LINK_STATUS and Value = SYMMETRIC in
the HELLO message, then for the current Neighbor Tuple:
3. Otherwise the set of MPRs of a router MAY be recalculated if the * N_mpr_selector := false
N_willingness of a Neighbor Tuple with N_symmetric = true changes
in any other way; it SHOULD be recalculated if N_mpr = false and
this is an increase in N_willingness or if N_mpr = true and this
is a decrease in N_willingness.
If the set of MPRs of a router is recalculated, this MUST be as * N_advertised := false
described in Section 14. Before that calculation, the N_mpr of all
Neighbor Tuples are set false. After that calculation the N_mpr of
all Neighbor Tuples representing symmetric 1-hop neighbors which are
chosen as MPRs, are set true.
11. TC Message Generation 11. TC Message Generation
A router with one or more OLSRv2 interfaces, and with a non-empty A router with one or more OLSRv2 interfaces, and with any Neighbor
Advertised Neighbor Set or a non-empty Local Attached Network Set Tuples with N_advertised = true, or with a non-empty Local Attached
MUST generate TC messages. A router with an empty Advertised Network Set MUST generate TC messages. A router which does not have
Neighbor Set and empty Local Attached Network Set SHOULD also such information to advertise SHOULD also generate "empty" TC
generate "empty" TC messages for a period A_HOLD_TIME after it last messages for a period A_HOLD_TIME after it last generated a non-empty
generated a non-empty TC message. TC messages (non-empty and empty) TC message. TC messages (non-empty and empty) are generated
are generated according to the following: according to the following:
1. The message originator address MUST be set to the router's 1. The message originator address MUST be the router's originator
originator address. address.
2. The message hop count, if included, MUST be set to zero. 2. The message hop count, if included, MUST be set to zero.
3. The message hop limit MUST be set to a value greater than 1. A 3. The message hop limit MUST be set to a value greater than 1. A
router MAY use the same hop limit TC_HOP_LIMIT in all TC router MAY use the same hop limit TC_HOP_LIMIT in all TC
messages, or use different values of the hop limit TC_HOP_LIMIT messages, or use different values of the hop limit TC_HOP_LIMIT
in TC messages, see Section 5.8. in TC messages, see Section 5.8.
4. The message MUST contain a Message TLV with Type := CONT_SEQ_NUM 4. The message MUST contain a Message TLV with Type := CONT_SEQ_NUM
and Value := ANSN from the Advertised Neighbor Set. If the TC and Value := ANSN from the Neighbor Information Base. If the TC
message is complete then this Message TLV MUST have Type message is complete then this Message TLV MUST have Type
Extension := COMPLETE, otherwise it MUST have Type Extension := Extension := COMPLETE, otherwise it MUST have Type Extension :=
INCOMPLETE. INCOMPLETE. (Exception: a TC message MAY omit such a Message TLV
if the TC message is not reporting any addresses with associated
TLV with Type = NBR_ADDR_TYPE or Type = GATEWAY.)
5. The message MUST contain a Message TLV with Type := 5. The message MUST contain a Message TLV with Type :=
VALIDITY_TIME, as specified in [RFC5497]. If all TC messages are VALIDITY_TIME, as specified in [RFC5497]. If all TC messages are
sent with the same hop limit then this TLV MUST have Value := sent with the same hop limit then this TLV MUST have Value :=
T_HOLD_TIME. If TC messages are sent with different hop limits T_HOLD_TIME. If TC messages are sent with different hop limits
(more than one value of TC_HOP_LIMIT) then this TLV MUST specify (more than one value of TC_HOP_LIMIT) then this TLV MUST specify
times which vary with the number of hops distance appropriate to times which vary with the number of hops distance appropriate to
the chosen pattern of TC message hop limits, as specified in the chosen pattern of TC message hop limits, as specified in
[RFC5497], these times SHOULD be appropriate multiples of [RFC5497], these times SHOULD be appropriate multiples of
T_HOLD_TIME. T_HOLD_TIME.
6. The message MAY contain a Message TLV with Type := INTERVAL_TIME, 6. The message MAY contain a Message TLV with Type := INTERVAL_TIME,
as specified in [RFC5497]. If all TC messages are sent with the as specified in [RFC5497]. If all TC messages are sent with the
same hop limit then this TLV MUST have Value := TC_INTERVAL. If same hop limit then this TLV MUST have Value := TC_INTERVAL. If
TC messages are sent with different hop limits, then this TLV TC messages are sent with different hop limits, then this TLV
MUST specify times which vary with the number of hops distance MUST specify times which vary with the number of hops distance
appropriate to the chosen pattern of TC message hop limits, as appropriate to the chosen pattern of TC message hop limits, as
specified in [RFC5497], these times SHOULD be appropriate specified in [RFC5497], these times SHOULD be appropriate
multiples of TC_INTERVAL. multiples of TC_INTERVAL.
7. Unless the router has a single interface, with a single address 7. A complete message MUST include, and an incomplete message MAY
with maximum prefix length, and that address is the router's
originator address, the message MUST contain all of the router's
addresses (i.e. all addresses in an I_local_iface_addr_list) in
its Address Blocks.
8. All addresses of the router's interfaces that are included in an
Address Block MUST each be associated with a TLV with Type :=
LOCAL_IF and Value := UNSPEC_IF.
9. A complete message MUST include, and an incomplete message MAY
include, in its Address Blocks: include, in its Address Blocks:
1. Each A_neighbor_addr from the Advertised Neighbor Set; 1. N_orig_addr in each Neighbor Tuple with N_advertised = true,
associated with a TLV with Type := NBR_ADDR_TYPE and Value :=
ORIGINATOR (or Value := ROUTABLE_ORIG if also to be
associated with Value = ROUTABLE).
2. AL_net_addr from each Local Attached Neighbor Tuple, each 2. Each routable address in an N_neighbor_addr_list in each
Neighbor Tuple with N_advertised = true, associated with a
TLV with Type := NBR_ADDR_TYPE and Value := ROUTABLE (or
Value := ROUTABLE_ORIG if also to be associated with Value =
ORIGINATOR).
3. AL_net_addr in each Local Attached Neighbor Tuple, each
associated with a TLV with Type := GATEWAY and Value := associated with a TLV with Type := GATEWAY and Value :=
AL_dist. AL_dist.
11.1. TC Message: Transmission 11.1. TC Message Transmission
Complete TC messages are generated and transmitted periodically on Complete TC messages are generated and transmitted periodically on
all OLSRv2 interfaces, with a default interval between two all OLSRv2 interfaces, with a default interval between two
consecutive TC transmissions by the same router of TC_INTERVAL. consecutive TC transmissions by the same router of TC_INTERVAL.
TC messages MAY be generated in response to a change of contents, TC messages MAY be generated in response to a change in the
indicated by a change in ANSN. In this case a router MAY send a information which they are to advertise, indicated by a change in
complete TC message, and if so MAY re-start its TC message schedule. ANSN. In this case a router MAY send a complete TC message, and if
Alternatively a router MAY send an incomplete TC message with at so MAY re-start its TC message schedule. Alternatively a router MAY
least the new content in its Address Blocks. Note that a router send an incomplete TC message with at least the newly advertised
cannot report removal of advertised content using an incomplete TC addresses (i.e. not previously, but now, an N_orig_addr or an
message. N_neighbor_addr_list in a Neighbor Tuple with N_advertised = true, or
in an AL_net_addr) in its Address Blocks, with associated TLV(s).
Note that a router cannot report removal of advertised content using
an incomplete TC message.
When sending a TC message in response to a change of contents, a When sending a TC message in response to a change of advertised
router must respect a minimum interval of TC_MIN_INTERVAL between addresses, a router must respect a minimum interval of
generated TC messages. Sending an incomplete TC message MUST NOT TC_MIN_INTERVAL between generated TC messages. Sending an incomplete
cause the interval between complete TC messages to be increased, and TC message MUST NOT cause the interval between complete TC messages
thus a router MUST NOT send an incomplete TC message if within to be increased, and thus a router MUST NOT send an incomplete TC
TC_MIN_INTERVAL of the next scheduled complete TC message. message if within TC_MIN_INTERVAL of the next scheduled complete TC
message.
The generation of TC messages, whether scheduled or triggered by a The generation of TC messages, whether scheduled or triggered by a
change of contents MAY be jittered as described in [RFC5148]. The change of contents MAY be jittered as described in [RFC5148]. The
values of MAXJITTER used SHOULD be: values of MAXJITTER used SHOULD be:
o TP_MAXJITTER for periodic TC message generation; o TP_MAXJITTER for periodic TC message generation;
o TT_MAXJITTER for responsive TC message generation. o TT_MAXJITTER for responsive TC message generation.
TC messages are included in packets as specified in [RFC5444]. These TC messages are included in packets as specified in [RFC5444]. These
packets MAY contain other messages, including HELLO messages and TC packets MAY contain other messages, including HELLO messages and TC
messages with different originator addresses. TC messages are messages with different originator addresses. TC messages are
forwarded according to the specification in Section 7.3. forwarded according to the specification in Section 7.3.
12. TC Message Processing 12. TC Message Processing
On receiving a TC message, a router MUST first check if the message On receiving a TC message, a router MUST first check if the message
skipping to change at page 40, line 27 skipping to change at page 45, line 37
Section 12.2. Section 12.2.
All TC message processing, including determination of whether a All TC message processing, including determination of whether a
message is invalid, unless otherwise noted considers only TLVs with message is invalid, unless otherwise noted considers only TLVs with
Type Extension = 0. TLVs with any other type extension (or any Type Extension = 0. TLVs with any other type extension (or any
unmentioned type extension when other type extensions are considered) unmentioned type extension when other type extensions are considered)
are ignored. All references to, for example, a TLV with Type = are ignored. All references to, for example, a TLV with Type =
VALIDITY_TIME refer to a TLV with Type = VALIDITY_TIME and Type VALIDITY_TIME refer to a TLV with Type = VALIDITY_TIME and Type
Extension = 0. Extension = 0.
Following TC message processing, if there are any changes in the
router's Information Bases, then the processing in Section 13 MUST be
performed.
12.1. Invalid Message 12.1. Invalid Message
A received TC message is invalid for processing by this router if any A received TC message is invalid for processing by this router if the
of the following conditions are true. message:
o The Message Header does not include an originator address, a o Does not include a message originator address, a message sequence
message sequence number, and a hop limit. number, and a hop limit.
o The Message Header a hop count, and contains a multi-value TLV o Does not include a hop count, and contains a multi-value TLV with
with Type = VALIDITY_TIME or Type == INTERVAL_TIME, as defined in Type = VALIDITY_TIME or Type = INTERVAL_TIME, as defined in
[RFC5497]. [RFC5497].
o The message does not have a single TLV with Type = VALIDITY_TIME o Does not have exactly one TLV with Type = VALIDITY_TIME in its
in its Message TLV Block.
o The message has more than one TLV with Type = INTERVAL_TIME in its
Message TLV Block. Message TLV Block.
o The message does not have a TLV with Type = CONT_SEQ_NUM and Type o Has more than one TLV with Type = INTERVAL_TIME in its Message TLV
Extension = COMPLETE or Type Extension = INCOMPLETE in its Message Block.
TLV Block.
o The message has more than one TLV with Type = CONT_SEQ_NUM and o Does not have a TLV with Type = CONT_SEQ_NUM and Type Extension =
Type Extension = COMPLETE or Type Extension = INCOMPLETE in its COMPLETE or Type Extension = INCOMPLETE in its Message TLV Block,
Message TLV Block, and these do not have the same type extension and contains at least one address associated with a TLV with Type
and the same Value. = NBR_ADDR_TYPE or Type = GATEWAY.
o The message has any Address Block TLV(s) with Type = LOCAL_IF and o Has more than one TLV with Type = CONT_SEQ_NUM and Type Extension
any single Value(s) which are not equal to UNSPEC_IF. = COMPLETE or Type Extension = INCOMPLETE in its Message TLV
Block.
o Any address associated with a TLV with Type = LOCAL_IF is one of o Has a message originator address, or any address associated with a
the receiving router's current or recently used addresses (i.e. is TLV with Type = NBR_ADDR_TYPE or Type = GATEWAY, that the
in any I_local_iface_addr_list in the Local Interface Set or is receiving router has recorded as:
equal to any IR_local_iface_addr in the Removed Interface Address
Set).
o Any address (including different copies of an address, in the same * its originator address, OR;
or different Address Blocks) is associated with more than one
single Value by one or more TLV(s) with Type = GATEWAY. * as the O_orig_addr in an Originator Tuple, OR;
* in an I_local_iface_addr_list in a Local Interface Tuple, OR;
* the IR_local_iface_addr in a Removed Interface Address Tuple.
o Has a message originator address, or any address associated with a
TLV with Type = NBR_ADDR_TYPE, that the receiving router has
recorded as the AL_net_addr in a Local Attached Network Tuple.
o Includes any address with a prefix length which is not maximal
(equal to the address length, in bits) associated with a TLV with
Type = NBR_ADDR_TYPE and Value = ORIGINATOR or Value =
ROUTABLE_ORIG.
o Includes any non-routable address associated with a TLV with Type
= NBR_ADDR_TYPE and Value = ROUTABLE or Value = ROUTABLE_ORIG.
o Includes any address associated with a TLV with Type =
NBR_ADDR_TYPE or Type = GATEWAY that is also the message's
originator address.
o Associates any address (including different copies of an address,
in the same or different Address Blocks) with more than one single
Value using one or more TLV(s) with Type = GATEWAY.
o Associates any address (including different copies of an address,
in the same or different Address Blocks) with TLVs with Type =
NBR_ADDR_TYPE and Type = GATEWAY.
A router MAY recognize additional reasons for identifying that a A router MAY recognize additional reasons for identifying that a
message is invalid. An invalid message MUST be silently discarded, message is invalid. An invalid message MUST be silently discarded,
without updating the router's Information Bases. without updating the router's Information Bases.
12.2. Initial TC Message Processing 12.2. TC Message Processing Definitions
When, according to Section 7.2, a TC message is to be "processed When, according to Section 7.2, a TC message is to be "processed
according to its type", this means that: according to its type", this means that:
o If the TC message contains a Message TLV with Type = CONT_SEQ_NUM o If the TC message contains a Message TLV with Type = CONT_SEQ_NUM
and Type Extension = COMPLETE, then processing according to and Type Extension = COMPLETE, then processing according to
Section 12.3 and then according to Section 12.4 is carried out. Section 12.3 and then according to Section 12.4 is carried out.
o If the TC message contains a Message TLV with Type = CONT_SEQ_NUM o If the TC message contains a Message TLV with Type = CONT_SEQ_NUM
and Type Extension = INCOMPLETE, then only processing according to and Type Extension = INCOMPLETE, then only processing according to
Section 12.3 is carried out. Section 12.3 is carried out.
For the purposes of this section: For the purposes of this section:
o "originator address" refers to the originator address in the TC
Message Header.
o "validity time" is calculated from a VALIDITY_TIME Message TLV in o "validity time" is calculated from a VALIDITY_TIME Message TLV in
the TC message according to the specification in [RFC5497]. All the TC message according to the specification in [RFC5497]. All
information in the TC message has the same validity time. information in the TC message has the same validity time.
o "ANSN" is defined as being the Value of a Message TLV with Type = o "received ANSN" is defined as being the Value of a Message TLV
CONT_SEQ_NUM. with Type = CONT_SEQ_NUM.
o "sending address list" refers to the list of addresses in all
Address Blocks which have associated TLV(s) with Type = LOCAL_IF
and Value = UNSPEC_IF. If the sending address list is otherwise
empty, then the message's originator address is added to the
sending address list, with maximum prefix length.
o Comparisons of sequence numbers are carried out as specified in o Comparisons of sequence numbers are carried out as specified in
Section 18. Section 17.
12.3. Initial TC Message Processing 12.3. Initial TC Message Processing
The TC message is processed as follows: The TC message is processed as follows:
1. The Advertising Remote Router Set is updated according to 1. The Advertising Remote Router Set is updated according to
Section 12.3.1; if the TC message is indicated as discarded in Section 12.3.1. If the TC message is indicated as discarded in
that processing then the following steps are not carried out. that processing then the following steps are not carried out.
2. The Topology Set is updated according to Section 12.3.2. 2. The Router Topology Set is updated according to Section 12.3.2.
3. The Attached Network Set is updated according to Section 12.3.3. 3. The Routable Address Topology Set is updated according to
Section 12.3.3.
4. The Attached Network Set is updated according to Section 12.3.4.
12.3.1. Populating the Advertising Remote Router Set 12.3.1. Populating the Advertising Remote Router Set
The router MUST update its Advertising Remote Router Set as follows: The router MUST update its Advertising Remote Router Set as follows:
1. If there is an Advertising Remote Router Tuple with: 1. If there is an Advertising Remote Router Tuple with:
* AR_orig_addr = originator address; AND * AR_orig_addr = message originator address; AND
* AR_seq_number > ANSN * AR_seq_number > received ANSN
then the TC message MUST be discarded. then the TC message MUST be discarded.
2. Otherwise: 2. Otherwise:
1. If there is no Advertising Remote Router Tuple such that: 1. If there is no Advertising Remote Router Tuple such that:
+ AR_orig_addr = originator address; + AR_orig_addr = message originator address;
then create an Advertising Remote Router Tuple with: then create an Advertising Remote Router Tuple with:
+ AR_orig_addr := originator address. + AR_orig_addr := message originator address.
2. This Advertising Remote Router Tuple (existing or new, the 2. This Advertising Remote Router Tuple (existing or new) is
"current tuple") is then modified as follows: then modified as follows:
+ AR_seq_number := ANSN; + AR_seq_number := received ANSN;
+ AR_time := current time + validity time. + AR_time := current time + validity time.
+ AR_addr_list := sending address list 12.3.2. Populating the Router Topology Set
3. For each other Advertising Remote Router Tuple (with a The router MUST update its Router Topology Set as follows:
different AR_orig_addr, the "other tuple") whose AR_addr_list
contains any address in the AR_addr_list of the current
tuple:
1. remove all Topology Tuples with T_orig_addr = 1. For each address (henceforth advertised address) in an Address
AR_orig_addr of the other tuple; Block that has an associated TLV with Type = NBR_ADDR_TYPE and
Value = ORIGINATOR or Value = ROUTABLE_ORIG, perform the
following processing:
2. remove all Attached Network Tuples with AN_orig_addr = 1. If there is no Router Topology Tuple such that:
AR_orig_addr of the other tuple;
3. remove the other tuple. + TR_from_orig_addr = message originator address; AND
12.3.2. Populating the Topology Set + TR_to_orig_addr = advertised address
The router MUST update its Topology Set as follows: then create a new Router Topology Tuple with:
+ TR_from_orig_addr := message originator address
+ TR_to_orig_addr := advertised address.
2. This Router Topology Tuple (existing or new) is then modified
as follows:
+ TR_seq_number := received ANSN;
+ TR_time := current time + validity time.
12.3.3. Populating the Routable Address Topology Set
The router MUST update its Routable Address Topology Set as follows:
1. For each address (henceforth advertised address) in an Address 1. For each address (henceforth advertised address) in an Address
Block that does not have an associated TLV with Type = LOCAL_IF, Block that has an associated TLV with Type = NBR_ADDR_TYPE and
or an associated TLV with Type = GATEWAY: Value = ROUTABLE or Value = ROUTABLE_ORIG, perform the following
processing:
1. If there is no Topology Tuple such that: 1. If there is no Routable Address Topology Tuple such that:
+ T_dest_addr = advertised address; AND + TA_from_orig_addr = message originator address; AND
+ T_orig_addr = originator address + TA_dest_addr = advertised address
then create a new Topology Tuple with: then create a new Routable Address Topology Tuple with:
+ T_dest_addr := advertised address; + TA_from_orig_addr := message originator address;
+ T_orig_addr := originator address. + TA_dest_addr := advertised address.
2. This Topology Tuple (existing or new) is then modified as 2. This Routable Address Topology Tuple (existing or new) is
follows: then modified as follows:
+ T_seq_number := ANSN; + TA_seq_number := received ANSN;
+ T_time := current time + validity time. + TA_time := current time + validity time.
12.3.3. Populating the Attached Network Set 12.3.4. Populating the Attached Network Set
The router MUST update its Attached Network Set as follows: The router MUST update its Attached Network Set as follows:
1. For each address (henceforth network address) in an Address Block 1. For each address (henceforth advertised address) in an Address
that does not have an associated TLV with Type = LOCAL_IF, and Block that has an associated TLV with Type = GATEWAY, and is not
does have an associated TLV with Type = GATEWAY: an AL_net_addr in a Local Attached Network Tuple, perform the
following processing:
1. If there is no Attached Network Tuple such that: 1. If there is no Attached Network Tuple such that:
+ AN_net_addr = network address; AND + AN_net_addr = network address; AND
+ AN_orig_addr = originator address + AN_orig_addr = message originator address
then create a new Attached Network Tuple with: then create a new Attached Network Tuple with:
+ AN_net_addr := network address; + AN_net_addr := network address;
+ AN_orig_addr := originator address + AN_orig_addr := message originator address.
2. This Attached Network Tuple (existing or new) is then 2. This Attached Network Tuple (existing or new) is then
modified as follows: modified as follows:
+ AN_dist := the Value of the associated GATEWAY TLV; + AN_dist := the Value of the associated GATEWAY TLV;
+ AN_seq_number := ANSN; + AN_seq_number := received ANSN;
+ AN_time := current time + validity time. + AN_time := current time + validity time.
12.4. Completing TC Message Processing 12.4. Completing TC Message Processing
The TC message is processed as follows: The TC message is processed as follows:
1. The Topology Set is updated according to Section 12.4.1. 1. The Router Topology Set is updated according to Section 12.4.1.
2. The Attached Network Set is updated according to Section 12.4.2. 2. The Routable Address Topology Set is updated according to
Section 12.4.2.
12.4.1. Purging the Topology Set 3. The Attached Network Set is updated according to Section 12.4.3.
The Topology Set MUST be updated as follows: 12.4.1. Purging the Router Topology Set
1. Any Topology Tuples with: The Router Topology Set MUST be updated as follows:
* T_orig_addr = originator address; AND 1. Any Router Topology Tuples with:
* T_seq_number < ANSN * TR_from_orig_addr = message originator address; AND
* TR_seq_number < received ANSN
MUST be removed. MUST be removed.
12.4.2. Purging the Attached Network Set 12.4.2. Purging the Routable Address Topology Set
The Routable Address Topology Set MUST be updated as follows:
1. Any Routable Address Topology Tuples with:
* TA_from_orig_addr = message originator address; AND
* TA_seq_number < received ANSN
MUST be removed.
12.4.3. Purging the Attached Network Set
The Attached Network Set MUST be updated as follows: The Attached Network Set MUST be updated as follows:
1. Any Attached Network Tuples with: 1. Any Attached Network Tuples with:
* AN_orig_addr = originator address; AND * AN_orig_addr = message originator address; AND
* AN_seq_number < ANSN * AN_seq_number < received ANSN
MUST be removed. MUST be removed.
13. Information Base Changes 13. Information Base Changes
1. The Originator Set in the Local Information Base MUST be updated The changes described in the following sections MUST be carried out
when the router changes originator address. If there is no when any Information Base changes as indicated.
Originator Tuple with:
13.1. Originator Address Changes
If the router changes originator address, then:
1. If there is no Originator Tuple with:
* O_orig_addr = old originator address * O_orig_addr = old originator address
then create an Originator Tuple with: then create an Originator Tuple with:
* O_orig_addr := old originator address * O_orig_addr := old originator address
This Originator Tuple (existing or new) is then modified as The Originator Tuple (existing or new) with:
follows:
* O_orig_addr = new originator address
is then modified as follows:
* O_time := current time + O_HOLD_TIME * O_time := current time + O_HOLD_TIME
2. The Advertised Neighbor Set in the Topology Information Base MUST 13.2. Neighbor State Changes
be changed when the Neighbor Set changes. The following changes
are required:
1. If an address in an N_neighbor_addr_list in a Neighbor Tuple The N_mpr_selector and N_advertised flags in Neighbor Tuples MUST be
is removed (including when that Neighbor Tuple is removed) maintained according to the following rules:
and that address is also an A_neighbor_addr in an Advertised
Neighbor Tuple, then that Advertised Neighbor Tuple MUST be
removed.
2. If an address is added to an N_neighbor_addr_list in a 1. If N_symmetric = false, then N_mpr_selector = false and
Neighbor Tuple with N_mpr_selector = true (including when N_advertised = false.
such a Neighbor Tuple is added) or for each address in an
N_neighbor_addr_list in a Neighbor Tuple whose N_mpr_selector
has changed from false to true, and that address is not
already an A_neighbor_addr in an Advertised Neighbor Tuple,
then an Advertised Neighbor Tuple MUST be added to the
Advertised Neighbor Set with A_neighbor_addr equal to that
address.
Other changes to the Advertised Neighbor Set MAY be made when the 2. If N_mpr_selector = true, then N_advertised = true.
Neighbor Set changes, in particular if the N_mpr_selector of a
Neighbor Tuple changes from true to false, then the Advertised
Neighbor Tuples whose A_neighbor_addr are addresses in the
N_neighbor_addr_list of that Neighbor Tuple MAY be removed.
3. The Topology Set and the Attached Network Set in the Topology 3. In other cases (i.e. N_symmetric = true and N_mpr_selector =
Information Base MUST be changed when an Advertising Remote false) a router MAY select N_advertised = true or N_advertised =
Router Tuple expires (AR_time is reached). The following changes false. The more neighbors that are advertised, the larger TC
are required before the Advertising Remote Router Tuple is messages become, but the more redundancy is available for
removed: routing. A router SHOULD consider the nature of its network in
making such a decision, and SHOULD avoid unnecessary changes in
advertising status, which may result both in additional TC
messages having to be sent by its neighbors, and in unnecessary
changes to routing, which will have similar effects to other
forms of topology changes in the MANET.
1. All Topology Tuples with: 13.3. Advertised Neighbor Changes
+ T_orig_addr = AR_orig_addr of the Advertising Remote The router MUST increment the ANSN in the Neighbor Information Base
Router Tuple whenever:
are removed. 1. Any Neighbor Tuple changes its N_advertised value.
2. All Attached Network Tuples with: 2. N_orig_addr is changed, or any routable address is added to or
removed from any Neighbor Tuple with N_advertised = true.
+ AN_orig_addr = AR_orig_addr of the Advertising Remote 3. There is any change to the Local Attached Network Set.
Router Tuple
are removed. 13.4. Advertising Remote Router Tuple Expires
The Router Topology Set, the Routable Address Topology Set and the
Attached Network Set MUST be changed when an Advertising Remote
Router Tuple expires (AR_time is reached). The following changes are
required before the Advertising Remote Router Tuple is removed:
1. All Router Topology Tuples with:
* TR_from_orig_addr = AR_orig_addr of the Advertising Remote
Router Tuple
are removed.
2. All Routable Address Topology Tuples with:
* TA_from_orig_addr = AR_orig_addr of the Advertising Remote
Router Tuple
are removed.
3. All Attached Network Tuples with:
* AN_orig_addr = AR_orig_addr of the Advertising Remote Router
Tuple
are removed.
13.5. Neighborhood Changes and MPR Updates
The set of symmetric 1-hop neighbors selected as MPRs MUST satisfy
the conditions defined in Section 14. To ensure this:
1. The set of MPRs of a router MUST be recalculated if:
* a Link Tuple is added with L_status = SYMMETRIC, OR;
* a Link Tuple with L_status = SYMMETRIC is removed, OR;
* a Link Tuple with L_status = SYMMETRIC changes to having
L_status = HEARD or L_status = LOST, OR;
* a Link Tuple with L_status = HEARD or L_status = LOST changes
to having L_status = SYMMETRIC, OR;
* a 2-Hop Tuple is added or removed, OR;
* the N_willingness of a Neighbor Tuple with N_symmetric = true
changes from WILL_NEVER to any other value, OR;
* the N_willingness of a Neighbor Tuple with N_symmetric = true
and N_mpr = true changes to WILL_NEVER from any other value,
OR;
* the N_willingness of a Neighbor Tuple with N_symmetric = true
and N_mpr = false changes to WILL_ALWAYS from any other value.
2. Otherwise, the set of MPRs of a router MAY be recalculated if the
N_willingness of a Neighbor Tuple with N_symmetric = true changes
in any other way; it SHOULD be recalculated if N_mpr = false and
this is an increase in N_willingness or if N_mpr = true and this
is a decrease in N_willingness.
If the set of MPRs of a router is recalculated, this MUST be as
described in Section 14. Before that calculation, the N_mpr of all
Neighbor Tuples are set false (although the previous values of N_mpr
MAY be used by an algorithm that minimises changes to the set of
MPRs). After that calculation the N_mpr of all Neighbor Tuples
representing symmetric 1-hop neighbors which are chosen as MPRs, are
set true.
13.6. Routing Set Updates
The Routing Set MUST be updated, as described in Section 15 when
changes in the Local Information Base, the Neighborhood Information
Base or the Topology Information Base indicate a change of the known
symmetric links and/or attached networks in the MANET, hence changing
the Topology Graph. It is sufficient to consider only changes which
affect at least one of:
o The Local Interface Set, if the change removes any address in an
I_local_iface_addr_list. In this case, unless the OLSRv2
interface is removed, it may not be necessary to do more than
replace such addresses, if used, by an alternative address from
the same I_local_iface_addr_list.
o The Local Attached Set, if the change removes any AL_net_addr
which is also an AN_net_addr. In this case it may not be
necessary to do more than add and remove Routing Tuples with
R_dest_addr equal to that AN_net_addr.
o The Link Set of any OLSRv2 interface, and to consider only Link
Tuples which have, or just had, L_status = SYMMETRIC (including
removal of such Link Tuples).
o The Neighbor Set of the router, and to consider only Neighbor
Tuples that have, or just had, N_symmetric = true, and do not have
N_orig_addr = unknown.
o The 2-Hop Set of any OLSRv2 interface, if used in the creation of
the Routing Set.
o The Router Topology Set of the router.
o The Routable Address Topology Set of the router.
o The Attached Network Set of the router.
14. Selecting MPRs 14. Selecting MPRs
Each router MUST select, from among its willing symmetric 1-hop Each router MUST select, from among its willing symmetric 1-hop
neighbors, a subset of routers as MPRs. MPRs are used to flood neighbors, a subset of these routers as MPRs. Only MPRs forward
control messages from a router into the network, while reducing the control messages flooded through the MANET, thus effecting a flooding
number of retransmissions that will occur in a region. Thus, the reduction, an optimization of the classical flooding mechanism, known
concept of MPR flooding is an optimization of a classical flooding as MPR flooding. MPRs MAY also be used to effect a topology
mechanism. MPRs MAY also be used to reduce the shared topology reduction in the MANET. Consequently, while it is not essential that
information in the network. Consequently, while it is not essential the set of MPRs is minimal, keeping the number of MPRs small ensures
that the set of MPRs is minimal, keeping the number of MPRs small that the overhead is kept at a minimum.
ensures that the overhead of OLSRv2 is kept at a minimum.
A router MUST select MPRs for each of its OLSRv2 interfaces, but then A router MUST select MPRs for each of its OLSRv2 interfaces, but then
forms the union of those sets as its single set of MPRs. This union forms the union of those sets as its single set of MPRs. This union
MUST include all symmetric 1-hop neighbors with willingness MUST include all symmetric 1-hop neighbors with willingness
WILL_ALWAYS. Only this overall set of MPRs is relevant, the recorded WILL_ALWAYS. Only this overall set of MPRs is relevant, the recorded
and used MPR relationship is one of routers, not interfaces. Routers and used MPR relationship is one of routers, not interfaces. Routers
MAY select their MPRs by any process which satisfies the conditions MAY select their MPRs by any process which satisfies the conditions
which follow. Routers can freely interoperate whether they use the which follow. Routers can freely interoperate whether they use the
same or different MPR selection algorithms. same or different MPR selection algorithms.
For each OLSRv2 interface a router MUST select a set of MPRs. This For each OLSRv2 interface a router MUST select a set of MPRs. This
set MUST have the properties that: set MUST have the properties that:
o All of the selected MPRs are willing symmetric 1-hop neighbors, o All of the selected MPRs are willing symmetric 1-hop neighbors,
AND; AND;
o If the selecting router sends a message on that OLSRv2 interface, o If the selecting router sends a message on that OLSRv2 interface,
and that message is successfully forwarded by all of the selected and that message is successfully forwarded by all of the selected
MPRs for that interface, then all symmetric strict 2-hop neighbors MPRs for that interface, then all symmetric strict 2-hop neighbors
of the selecting router through that OLSRv2 interface will receive of the selecting router through that OLSRv2 interface will receive
that message on a symmetric link. that message over a symmetric link.
Note that it is always possible to select a valid set of MPRs. The Note that it is always possible to select a valid set of MPRs. The
set of all willing symmetric 1-hop neighbors of a router is a set of all willing symmetric 1-hop neighbors of a router is a
(maximal) valid set of MPRs for that router. However a router SHOULD (maximal) valid set of MPRs for that router. However a router SHOULD
NOT select a symmetric 1-hop neighbor with Willingness != WILL_ALWAYS NOT select a symmetric 1-hop neighbor with Willingness != WILL_ALWAYS
as an MPR if there are no symmetric strict 2-hop neighbors with a as an MPR if there are no symmetric strict 2-hop neighbors with a
symmetric link to that symmetric 1-hop neighbor. Thus a router with symmetric link to that symmetric 1-hop neighbor. Thus a router with
no symmetric 1-hop neighbors with willingness WILL_ALWAYS and with no no symmetric 1-hop neighbors with willingness WILL_ALWAYS and with no
symmetric strict 2-hop neighbors SHOULD NOT select any MPRs. symmetric strict 2-hop neighbors SHOULD NOT select any MPRs.
A router MAY select its MPRs for each OLSRv2 interface independently, A router MAY select its MPRs for each OLSRv2 interface independently,
or it MAY coordinate its MPR selections across its OLSRv2 interfaces, or it MAY coordinate its MPR selections across its OLSRv2 interfaces,
as long as the required condition is satisfied for each OLSRv2 as long as the required condition is satisfied for each OLSRv2
interface. Each router MAY select its MPRs independently from the interface. Each router MAY select its MPRs independently from the
MPR selection by other routers, or it MAY, for example, give MPR selection by other routers, or it MAY, for example, give
preference to routers that either are, or are not, already selected preference to routers that either are, or are not, already selected
as MPRs by other routers. as MPRs by other routers.
When selecting MPRs for each OLSRv2 interface independently, this MAY When selecting MPRs for each OLSRv2 interface independently, this MAY
be done using information from the Link Set and 2-Hop Set of that be done using information from the Link Set and 2-Hop Set of that
OLSRv2 interface, and the Neighbor Set of the router (specifically OLSRv2 interface only, and the Neighbor Set of the router
the N_willingness elements). (specifically the N_willingness elements).
The selection of MPRs (overall, not per OLSRv2 interface) is recorded The selection of MPRs (overall, not per OLSRv2 interface) is recorded
in the Neighbor Set of the router (using the N_mpr elements). A in the Neighbor Set of the router (using the N_mpr elements). A
selected MPR MUST be a willing symmetric 1-hop neighbor (i.e. the selected MPR MUST be a willing symmetric 1-hop neighbor (i.e. the
corresponding N_symmetric = true, and the corresponding N_willingness corresponding N_symmetric = true, and the corresponding N_willingness
!= WILL_NEVER). != WILL_NEVER).
A router MUST recalculate its MPRs whenever the currently selected A router MUST recalculate its MPRs whenever the currently selected
set of MPRs does not still satisfy the required conditions. It MAY set of MPRs does not still satisfy the required conditions. It MAY
recalculate its MPRs if the current set of MPRs is still valid, but recalculate its MPRs if the current set of MPRs is still valid, but
could be more efficient. It is sufficient to recalculate a router's could be more efficient. Sufficient conditions to recalculate a
MPRs when there is a change to any of the router's Link Sets router's set of MPRs are given in Section 13.5.
affecting the symmetry of any link (addition or removal of a Link
Tuple with L_status = SYMMETRIC, or change of any L_status to or from
SYMMETRIC), any change to any of the router's 2-Hop Sets, or a change
of the N_willingness (to or from WILL_NEVER or to WILL_ALWAYS is
sufficient) of any Neighbor Tuple with N_symmetric = true.
An algorithm that creates a set of MPRs that satisfies the required
conditions is given in Appendix B.
15. Populating Derived Sets
The Relay Sets and the Advertised Neighbor Set of a router are
denoted derived sets, since updates to these sets are not directly a
function of message exchanges, but rather are derived from updates to
other sets, in particular to the MPR selector status of other routers
recorded in the Neighbor Set.
15.1. Populating the Relay Set
The Relay Set for an OLSRv2 interface contains the set of OLSRv2 An example algorithm that creates a set of MPRs that satisfies the
interface addresses of those symmetric 1-hop neighbors for which this required conditions is given in Appendix A.
OLSRv2 interface is to relay broadcast traffic. This set MUST
contain only addresses of OLSRv2 interfaces with which this OLSRv2
interface has a symmetric link. This set MUST include all such
addresses of all such OLSRv2 interfaces of routers which are MPR
selectors of this router.
The Relay Set for an OLSRv2 interface of this router is thus created 15. Routing Set Calculation
by:
1. For each Link Tuple in the Link Set for this OLSRv2 interface The Routing Set of a router is populated with Routing Tuples that
with L_status = SYMMETRIC, and the corresponding Neighbor Tuple represent paths from that router to all destinations in the network.
with N_neighbor_addr_list containing L_neighbor_iface_addr_list: These paths are calculated based on the Network Topology Graph, which
is constructed from information in the Information Bases, obtained
via HELLO and TC message exchange.
1. All addresses from L_neighbor_iface_addr_list MUST be Changes to the Routing Set do not require any messages to be
included in the Relay Set of this OLSRv2 interface if transmitted. The state of the Routing Set SHOULD, however, be
N_mpr_selector = true, and otherwise MAY be so included. reflected in IP's routing table by adding and removing entries from
IP's routing table as appropriate. Only appropriate Routing Tuples
(in particular only those that represent local links or paths to
routable addresses) need be reflected in IP's routing table.
15.2. Populating the Advertised Neighbor Set 15.1. Network Topology Graph
The Advertised Neighbor Set of a router contains all addresses of The Network Topology Graph is formed from information from the
those symmetric 1-hop neighbors to which the router advertises a link router's Local Interface Set, Link Sets, Neighbor Set, Router
in its TC messages. This set MUST include all addresses in all MPR Topology Set, Routable Address Topology Set and Attached Network Set.
selector of this router. The Network Topology Graph MAY also use information from the router's
2-Hop Sets. The Network Topology Graph forms the router's
topological view of the network in form of a directed graph. The
Network Topology Graph has a "backbone" (within which minimum
distance routes will be constructed) containing the following edges:
The Advertised Neighbor Set for this router is thus created by: o Edges X -> Y for all possible Y, and one X per Y, such that:
1. For each Neighbor Tuple with N_symmetric = true: * Y is the N_orig_addr of a Neighbor Tuple, AND;
1. All addresses from N_neighbor_addr_list MUST be included in * N_orig_addr is not unknown;
the Advertised Neighbor Set if N_mpr_selector = true, and
otherwise MAY be so included.
Whenever address(es) are added to or removed from the Advertised * X is in the I_local_iface_addr_list of a Local Interface Tuple,
Neighbor Set, its ANSN MUST be incremented. AND;
16. Routing Set Calculation * There is a Link Tuple with L_status = SYMMETRIC such that this
Neighbor Tuple and this Local Interface Tuple correspond to it.
An address from L_neighbor_iface_addr_list will be denoted R in
this case.
The Routing Set of a router is populated with Routing Tuples that It SHOULD be preferred, where possible, to select R = S and X from
represent paths from that router to all destinations in the network. the Local Interface Tuple corresponding to the Link Tuple from
These paths are calculated based on the Network Topology Graph, which which R was selected.
is constructed from information in the Information Bases, obtained
via HELLO and TC message exchange.
16.1. Network Topology Graph o All edges W -> U such that:
The Network Topology Graph is formed from information from the * W is the TR_from_orig_addr of a Router Topology Tuple, AND;
router's Link Sets, Neighbor Set, Topology Set and Attached Network
Set. The Network Topology Graph SHOULD also use information from the
router's 2-Hop Sets. The Network Topology Graph forms that router's
topological view of the network in form of a directed graph,
containing the following arcs:
o Local symmetric links - all arcs X -> Y such that: * U is the TR_to_orig_addr of the same Router Topology Tuple.
* X is an address in the I_local_iface_addr_list of a Local The Network Topology Graph is further "decorated" with the following
Interface Tuple of this router, AND; edges. If an address S, V, Z or T equals an address Y or W, then the
edge terminating in the address S, V, Z or T MUST NOT be used in any
path.
* Y is an address in the L_neighbor_iface_addr_list of a Link o Edges X -> S for all possible S, and one X per S, such that:
Tuple in the corresponding (to the OLSRv2 interface of that
I_local_iface_addr_list) Link Set which has L_status =
SYMMETRIC.
o 2-hop symmetric links - all arcs Y -> Z such that: * S is in the N_neighbor_addr_list of a Neighbor Tuple, AND;
* Y is an address in the L_neighbor_iface_addr_list of a Link * X is in the I_local_iface_addr_list of a Local Interface Tuple,
Tuple, in any of the router's Link Sets, which has L_status = AND;
SYMMETRIC, AND;
* the Neighbor Tuple with Y in its N_neighbor_addr_list has * There is a Link Tuple with L_status = SYMMETRIC such that this
N_willingness not equal to WILL_NEVER, AND; Neighbor Tuple and this Local Interface Tuple correspond to it.
An address from L_neighbor_iface_addr_list will be denoted R in
this case.
* Z is the N2_2hop_addr of a 2-Hop Tuple in the 2-Hop Set It SHOULD be preferred, where possible, to select R = S and X from
corresponding to the OLSRv2 interface of the chosen Link Set. the Local Interface Tuple corresponding to the Link Tuple from
which R was selected.
o Advertised symmetric links - all arcs U -> V such that there o All edges W -> V such that:
exists a Topology Tuple and a corresponding Advertising Remote
Router Tuple (i.e. with AR_orig_addr = T_orig_addr) with:
* U is in the AR_addr_list of the Advertising Remote Router * W is the TA_from_orig_addr of a Routable Address Topology
Tuple, AND; Tuple, AND;
* V is the T_dest_addr of the Topology Tuple. * V is the TA_dest_addr of the same Routable Address Topology
Tuple.
o Symmetric 1-hop neighbor addresses - all arcs Y -> W such that:
* Y is, and W is not, an address in the o All edges W -> T such that:
L_neighbor_iface_addr_list of a Link Tuple, in any of the
router's Link Sets, which has L_status = SYMMETRIC, AND;
* W and Y are included in the same N_neighbor_addr_list (i.e. the * W is the AN_orig_addr of an Attached Network Tuple, AND;
one in the Neighbor Tuple whose N_neighbor_addr_list contains * T is the AN_net_addr of the same Attached Network Tuple.
the L_neighbor_iface_addr_list that includes Y).
o Attached network addresses - all arcs U -> T such that there o OPTIONALLY, all edges Y -> Z such that:
exists an Attached Network Tuple and a corresponding Advertising
Remote Router Tuple (i.e. with AR_orig_addr = AN_orig_addr) with:
* U is in the AR_addr_list of the Advertising Remote Router * Z is a routable address and is the N2_2hop_addr of a 2-Hop
Tuple, AND; Tuple, AND;
* T is the AN_net_addr of the Attached Network Tuple. * Y is the N_orig_addr of the corresponding Neighbor Tuple, AND;
All links in the first three cases above have a hop count of one, the * This Neighbor Tuple has N_willingness not equal to WILL_NEVER.
symmetric 1-hop neighbor addresses have a hop count of zero, and the
attached network addresses have a hop count given by the appropriate
value of AN_dist.
16.2. Populating the Routing Set A path terminating with such an edge SHOULD NOT be used in
preference to any other path.
Any part of the Topology Graph which is not connected to an address X
is not used. Only one selection X need be made from each
I_local_iface_addr_list, and only one selection R need be made from
any L_neighbor_iface_addr_list. All edges have a cost (hop count) of
one, except edges W -> T which each have a cost (hop count) equal to
the appropriate value of AN_dist.
15.2. Populating the Routing Set
The Routing Set MUST contain the shortest paths for all destinations The Routing Set MUST contain the shortest paths for all destinations
from all local OLSRv2 interfaces using the Network Topology Graph. from all local OLSRv2 interfaces using the Network Topology Graph.
This calculation MAY use any algorithm, including any means of This calculation MAY use any algorithm, including any means of
choosing between paths of equal length. choosing between paths of equal length.
Using the notation of Section 16.1, each path will have as its first Using the notation of Section 15.1, initially "backbone" paths using
arc a local symmetric link X -> Y. There will be a path for each only edges X -> Y and W -> U need be constructed (using a minimum
terminating Y, Z, V, W and T which can be connected to local OLSRv2 distance algorithm). Then paths using only a final edge of the other
address X using the indicated arcs. The corresponding Routing Tuple types may be added. These MUST NOT replace backbone paths with the
for this path will have: same destination (and paths terminating in an edge Y -> Z SHOULD NOT
replace paths with any other form of terminating edge).
o R_dest_addr := the terminating Y, Z, V, W or T;
o R_next_iface_addr := the first arc's Y; Each path will correspond to a Routing Tuple. These will be of two
types. The first type will represent single edge paths, of type X ->
S or X -> Y, by:
o R_dist := the total hop count of the path; o R_local_iface_addr := X;
o R_local_iface_addr := the first arc's X. o R_next_iface_addr := R;
An example algorithm for calculating the Routing Set of a router is o R_dest_addr := S or Y;
given in Appendix C.
16.3. Routing Set Updates o R_dist := 1,
The Routing Set MUST be updated when changes in the Neighborhood where R is as defined in Section 15.1 for these types of edges.
Information Base or the Topology Information Base indicate a change
of the known symmetric links and/or attached networks in the MANET.
It is sufficient to consider only changes which affect at least one
of:
o The Link Set of any OLSRv2 interface, and to consider only Link The second type will represent a multiple edge path, which will
Tuples which have, or just had, L_status = SYMMETRIC (including always have first edge of type X -> Y, and will have final edge of
removal of such Link Tuples). type W -> U, W -> V, W -> T or Y -> Z. The Routing Tuple will be:
o The Neighbor Set of the router, and to consider only Neighbor o R_local_iface_addr := X;
Tuples that have, or just had, N_symmetric = true.
o The 2-Hop Set of any OLSRv2 interface. o R_next_iface_addr := Y;
o The Advertising Remote Router Set of the router. o R_dest_addr := U, V, T or Z;
o The Topology Set of the router. o R_dist := the total hop count of the path.
o The Attached Network Set of the router. Finally, Routing Tuples of the second type whose R_dest_addr is not
routable MAY be discarded.
Updates to the Routing Set do not generate or trigger any messages to An example algorithm for calculating the Routing Set of a router is
be transmitted. The state of the Routing Set SHOULD, however, be given in Appendix B.
reflected in the IP routing table by adding and removing entries from
the IP routing table as appropriate.
17. Proposed Values for Parameters and Constants 16. Proposed Values for Parameters and Constants
OLSRv2 uses all parameters and constants defined in [NHDP] and This protocol uses all parameters and constants defined in [NHDP] and
additional parameters and constants defined in this document. All additional parameters and constants defined in this document. All
but one (RX_HOLD_TIME) of these additional parameters are router but one (RX_HOLD_TIME) of these additional parameters are router
parameters as defined in [NHDP]. These proposed values of the parameters as defined in [NHDP]. These proposed values of the
additional parameters are appropriate to the case where all additional parameters are appropriate to the case where all
parameters (including those defined in [NHDP]) have a single value. parameters (including those defined in [NHDP]) have a single value.
Proposed values for parameters defined in [NHDP] are given in that Proposed values for parameters defined in [NHDP] are given in that
document. document.
17.1. Local History Time Parameters 16.1. Local History Time Parameters
o O_HOLD_TIME := 30 seconds o O_HOLD_TIME := 30 seconds
17.2. Message Interval Parameters 16.2. Message Interval Parameters
o TC_INTERVAL := 5 seconds o TC_INTERVAL := 5 seconds
o TC_MIN_INTERVAL := TC_INTERVAL/4 o TC_MIN_INTERVAL := TC_INTERVAL/4
17.3. Advertised Information Validity Time Parameters 16.3. Advertised Information Validity Time Parameters
o T_HOLD_TIME := 3 x TC_INTERVAL o T_HOLD_TIME := 3 x TC_INTERVAL
o A_HOLD_TIME := T_HOLD_TIME o A_HOLD_TIME := T_HOLD_TIME
17.4. Received Message Validity Time Parameters 16.4. Received Message Validity Time Parameters
o RX_HOLD_TIME := 30 seconds o RX_HOLD_TIME := 30 seconds
o P_HOLD_TIME := 30 seconds o P_HOLD_TIME := 30 seconds
o F_HOLD_TIME := 30 seconds o F_HOLD_TIME := 30 seconds
17.5. Jitter Time Parameters 16.5. Jitter Time Parameters
o TP_MAXJITTER := HP_MAXJITTER o TP_MAXJITTER := HP_MAXJITTER
o TT_MAXJITTER := HT_MAXJITTER o TT_MAXJITTER := HT_MAXJITTER
o F_MAXJITTER := TT_MAXJITTER o F_MAXJITTER := TT_MAXJITTER
17.6. Hop Limit Parameter 16.6. Hop Limit Parameter
o TC_HOP_LIMIT := 255 o TC_HOP_LIMIT := 255
17.7. Willingness Parameter and Constants 16.7. Willingness Parameter and Constants
o WILLINGNESS := WILL_DEFAULT o WILLINGNESS := WILL_DEFAULT
o WILL_NEVER := 0 o WILL_NEVER := 0
o WILL_DEFAULT := 3 o WILL_DEFAULT := 3
o WILL_ALWAYS := 7 o WILL_ALWAYS := 7
18. Sequence Numbers 17. Sequence Numbers
Sequence numbers are used in OLSRv2 with the purpose of discarding Sequence numbers are used in this specification for the purpose of
"old" information, i.e. messages received out of order. However with discarding "old" information, i.e. messages received out of order.
a limited number of bits for representing sequence numbers, wrap- However with a limited number of bits for representing sequence
around (that the sequence number is incremented from the maximum numbers, wrap-around (that the sequence number is incremented from
possible value to zero) will occur. To prevent this from interfering the maximum possible value to zero) will occur. To prevent this from
with the operation of OLSRv2, the following MUST be observed when interfering with the operation of this protocol, the following MUST
determining the ordering of sequence numbers. be observed when determining the ordering of sequence numbers.
The term MAXVALUE designates in the following one more than the The term MAXVALUE designates in the following one more than the
largest possible value for a sequence number. For a 16 bit sequence largest possible value for a sequence number. For a 16 bit sequence
number (as are those defined in this specification) MAXVALUE is number (as are those defined in this specification) MAXVALUE is
65536. 65536.
The sequence number S1 is said to be "greater than" the sequence The sequence number S1 is said to be "greater than" the sequence
number S2 if: number S2 if:
o S1 > S2 AND S1 - S2 < MAXVALUE/2 OR o S1 > S2 AND S1 - S2 < MAXVALUE/2 OR
skipping to change at page 53, line 25 skipping to change at page 61, line 17
o S2 > S1 AND S2 - S1 > MAXVALUE/2 o S2 > S1 AND S2 - S1 > MAXVALUE/2
When sequence numbers S1 and S2 differ by MAXVALUE/2 their ordering When sequence numbers S1 and S2 differ by MAXVALUE/2 their ordering
cannot be determined. In this case, which should not occur, either cannot be determined. In this case, which should not occur, either
ordering may be assumed. ordering may be assumed.
Thus when comparing two messages, it is possible - even in the Thus when comparing two messages, it is possible - even in the
presence of wrap-around - to determine which message contains the presence of wrap-around - to determine which message contains the
most recent information. most recent information.
19. IANA Considerations 18. Extensions
19.1. Message Types
This specification defines one Message Type, to be allocated from the
0-223 range of the "Message Types" namespace defined in [RFC5444], as
specified in Table 5.
+------+------+-----------------------------------------+
| Name | Type | Description |
+------+------+-----------------------------------------+
| TC | TBD1 | Topology Control (MANET-wide signaling) |
+------+------+-----------------------------------------+
Table 5
19.2. Message TLV Types
This specification defines two Message TLV Types, which must be
allocated from the "Message TLV Types" namespace defined in
[RFC5444]. IANA are requested to make allocations in the 8-127 range
for these types. This will create two new type extension registries
with assignments as specified in Table 6 and Table 7. Specifications
of these TLVs are in Section 8.1.1 and Section 8.2.1.
+-------------+------+-----------+----------------------------------+
| Name | Type | Type | Description |
| | | extension | |
+-------------+------+-----------+----------------------------------+
| MPR_WILLING | TBD2 | 0 | Specifies the originating |
| | | | router's willingness to act as a |
| | | | relay and to partake in network |
| | | | formation |
| Unassigned | TBD2 | 1-255 | Expert Review |
+-------------+------+-----------+----------------------------------+
Table 6
+--------------+------+----------------+----------------------------+
| Name | Type | Type extension | Description |
+--------------+------+----------------+----------------------------+
| CONT_SEQ_NUM | TBD3 | 0 (COMPLETE) | Specifies a content |
| | | | sequence number for this |
| | | | complete message |
| CONT_SEQ_NUM | TBD3 | 1 (INCOMPLETE) | Specifies a content |
| | | | sequence number for this |
| | | | incomplete message |
| Unassigned | TBD3 | 2-255 | Expert Review |
+--------------+------+----------------+----------------------------+
Table 7
Type extensions indicated as Expert Review SHOULD be allocated as
described in [RFC5444], based on Expert Review as defined in
[RFC5226].
19.3. Address Block TLV Types
This specification defines two Address Block TLV Types, which must be
allocated from the "Address Block TLV Types" namespace defined in
[RFC5444]. IANA are requested to make allocations in the 8-127 range
for these types. This will create two new type extension registries
with assignments as specified in Table 8 and Table 9. Specifications
of these TLVs are in Section 8.1.2 and Section 8.2.2.
+------------+------+-----------+-----------------------------------+ An extension to this protocol will need to interact with this
| Name | Type | Type | Description | specification, and possibly also with [NHDP]. This protocol is
| | | extension | | designed to permit such interactions, in particular:
+------------+------+-----------+-----------------------------------+
| MPR | TBD4 | 0 | Specifies that a given address is |
| | | | of a router selected as an MPR |
| Unassigned | TBD4 | 1-255 | Expert Review |
+------------+------+-----------+-----------------------------------+
Table 8 o Through accessing, and possibly extending, the information in the
Information Bases. All updates to the elements specified in this
document are subject to the constraints specified in [NHDP] and
Appendix D.
+------------+------+-----------+-----------------------------------+ o Through accessing an outgoing message prior to it being
| Name | Type | Type | Description | transmitted over any OLSRv2 interface, and to add information to
| | | extension | | it as specified in [RFC5444]. This MAY include Message TLVs
+------------+------+-----------+-----------------------------------+ and/or addresses with associated Address Block TLVs. (Addresses
| GATEWAY | TBD5 | 0 | Specifies that a given address is | without new associated TLVs SHOULD NOT be added to messages.)
| | | | reached via a gateway on the | This may, for example, be to allow a security protocol, as
| | | | originating router | suggested in Section 19, to add a TLV containing a cryptographic
| Unassigned | TBD5 | 1-255 | Expert Review | signature to the message.
+------------+------+-----------+-----------------------------------+
Table 9 o Through accessing an incoming message, and potentially discarding
it prior to processing by this protocol. This may, for example,
allow a security protocol as suggested in Section 19 to perform
verification of message signatures and prevent processing and/or
forwarding of unverifiable messages by this protocol.
Type extensions indicated as Expert Review SHOULD be allocated as o Through accessing an incoming message after it has been completely
described in [RFC5444], based on Expert Review as defined in processed by this protocol. This may, in particular, allow a
[RFC5226]. protocol which has added information, by way of inclusion of
appropriate TLVs, or of addresses associated with new TLVs, access
to such information after appropriate updates have been recorded
in the Information Bases in this protocol.
The Address Block TLV with Type = LOCAL_IF defined in [NHDP] is o Through requesting that a message be generated at a specific time.
extended to also permit inclusion of the Value UNSPEC_IF = 2, In that case, message generation MUST still respect the
representing a local address which may or may not be that of the constraints in [NHDP] and Section 5.4.
interface on which this message is transmitted.
20. Security Considerations 19. Security Considerations
Currently, OLSRv2 does not specify any special security measures. As Currently, this protocol does not specify any special security
a proactive routing protocol, OLSRv2 makes a target for various measures. As a proactive routing protocol, this protocol is a
attacks. The various possible vulnerabilities are discussed in this potential target for various attacks. Various possible
section. vulnerabilities are discussed in this section.
20.1. Confidentiality 19.1. Confidentiality
Being a proactive protocol, OLSRv2 periodically MPR floods This protocol periodically MPR floods topological information to all
topological information to all routers in the network. Hence, if routers in the network. Hence, if used in an unprotected wireless
used in an unprotected wireless network, the network topology is network, the network topology is revealed to anyone who listens to
revealed to anyone who listens to OLSRv2 control messages. the control messages.
In situations where the confidentiality of the network topology is of In situations where the confidentiality of the network topology is of
importance, regular cryptographic techniques, such as exchange of importance, regular cryptographic techniques, such as exchange of
OLSRv2 control traffic messages encrypted by PGP [RFC4880] or OLSRv2 control traffic messages encrypted by PGP [RFC4880] or
encrypted by some shared secret key, can be applied to ensure that encrypted by some shared secret key, can be applied to ensure that
control traffic can be read and interpreted by only those authorized control traffic can be read and interpreted by only those authorized
to do so. to do so.
20.2. Integrity 19.2. Integrity
In OLSRv2, each router is injecting topological information into the Each router is injecting topological information into the network
network through transmitting HELLO messages and, for some routers, TC through transmitting HELLO messages and, for some routers, TC
messages. If some routers for some reason, malicious or malfunction, messages. If some routers for some reason, malicious or malfunction,
inject invalid control traffic, network integrity may be compromised. inject invalid control traffic, network integrity may be compromised.
Therefore, message authentication is recommended. Therefore, message authentication is recommended.
Different such situations may occur, for instance: Different such situations may occur, for instance:
1. a router generates TC messages, advertising links to non-neighbor 1. a router generates TC messages, advertising links to non-neighbor
routers; routers;
2. a router generates TC messages, pretending to be another router; 2. a router generates TC messages, pretending to be another router;
skipping to change at page 56, line 51 skipping to change at page 63, line 19
Authentication of the originator router for control messages (for Authentication of the originator router for control messages (for
situations 2, 4 and 5) and on the individual links announced in the situations 2, 4 and 5) and on the individual links announced in the
control messages (for situations 1 and 3) may be used as a control messages (for situations 1 and 3) may be used as a
countermeasure. However to prevent routers from repeating old (and countermeasure. However to prevent routers from repeating old (and
correctly authenticated) information (situation 9) temporal correctly authenticated) information (situation 9) temporal
information is required, allowing a router to positively identify information is required, allowing a router to positively identify
such delayed messages. such delayed messages.
In general, digital signatures and other required security In general, digital signatures and other required security
information may be transmitted as a separate OLSRv2 Message Type, or information may be transmitted as a separate Message Type, or
signatures and security information may be transmitted within the signatures and security information may be transmitted within the
OLSRv2 HELLO and TC messages, using the TLV mechanism. Either option HELLO and TC messages, using the TLV mechanism. Either option
permits that "secured" and "unsecured" routers can coexist in the permits that "secured" and "unsecured" routers can coexist in the
same network, if desired, same network, if desired,
Specifically, the authenticity of entire OLSRv2 control packets can Specifically, the authenticity of entire control packets can be
be established through employing IPsec authentication headers, established through employing IPsec authentication headers, whereas
whereas authenticity of individual links (situations 1 and 3) require authenticity of individual links (situations 1 and 3) require
additional security information to be distributed. additional security information to be distributed.
An important consideration is that all control messages in OLSRv2 are An important consideration is that all control messages are
transmitted either to all routers in the neighborhood (HELLO transmitted either to all routers in the neighborhood (HELLO
messages) or broadcast to all routers in the network (TC messages). messages) or broadcast to all routers in the network (TC messages).
For example, a control message in OLSRv2 is always a point-to- For example, a control message in this protocol is always a point-to-
multipoint transmission. It is therefore important that the multipoint transmission. It is therefore important that the
authentication mechanism employed permits that any receiving router authentication mechanism employed permits that any receiving router
can validate the authenticity of a message. As an analogy, given a can validate the authenticity of a message. As an analogy, given a
block of text, signed by a PGP private key, then anyone with the block of text, signed by a PGP private key, then anyone with the
corresponding public key can verify the authenticity of the text. corresponding public key can verify the authenticity of the text.
20.3. Interaction with External Routing Domains 19.3. Interaction with External Routing Domains
OLSRv2 does, through the use of TC messages, provide a basic This protocol does, through the use of TC messages, provide a basic
mechanism for injecting external routing information to the OLSRv2 mechanism for injecting external routing information to this
domain. Appendix A also specifies that routing information can be protocol's domain. Routing information can be extracted from the
extracted from the topology table or the routing table of OLSRv2 and, protocol's Information Bases, in particular the Routing Set, of this
potentially, injected into an external domain if the routing protocol protocol and, potentially, injected into an external domain, if the
governing that domain permits. routing protocol governing that domain permits this.
Other than as described in Appendix A, when operating routers When operating routers connecting a MANET using this protocol to an
connecting OLSRv2 to an external routing domain, care MUST be taken external routing domain, care MUST be taken not to allow potentially
not to allow potentially insecure and untrustworthy information to be insecure and untrustworthy information to be injected from this
injected from the OLSRv2 domain to external routing domains. Care domain to external routing domains. Care MUST also be taken to
MUST be taken to validate the correctness of information prior to it validate the correctness of information prior to it being injected as
being injected as to avoid polluting routing tables with invalid to avoid polluting routing tables with invalid information.
information.
A recommended way of extending connectivity from an existing routing A recommended way of extending connectivity from an existing routing
domain to an OLSRv2 routed MANET is to assign an IP prefix (under the domain to a MANET routed using this protocol is to assign an IP
authority of the routers/gateways connecting the MANET with the prefix (under the authority of the routers/gateways connecting the
exiting routing domain) exclusively to the OLSRv2 MANET area, and to MANET with the exiting routing domain) exclusively to that MANET
configure the gateways statically to advertise routes to that IP area, and to statically configure the gateways to advertise routes
sequence to routers in the existing routing domain. for that IP sequence to routers in the existing routing domain.
20. IANA Considerations
This specification defines one Message Type, which must be allocated
from the "Message Types" repository of [RFC5444], two Message TLV
Types, which must be allocated from the "Message TLV Types"
repository of [RFC5444], and three Address Block TLV Types, which
must be allocated from the "Address Block TLV Types" repository of
[RFC5444].
20.1. Expert Review: Evaluation Guidelines
For the registries where an Expert Review is required, the designated
expert SHOULD take the same general recommendations into
consideration as are specified by [RFC5444].
20.2. Message Types
This specification defines one Message Type, to be allocated from the
0-223 range of the "Message Types" namespace defined in [RFC5444], as
specified in Table 6.
+------+------+-----------------------------------------+
| Name | Type | Description |
+------+------+-----------------------------------------+
| TC | TBD1 | Topology Control (MANET-wide signaling) |
+------+------+-----------------------------------------+
Table 6: Message Type assignment
20.3. Message-Type-specific TLV Type Registries
IANA is requested to create a registry for Message-Type-specific
Message TLVs for TC messages, in accordance with Section 6.2.1 of
[RFC5444], and with initial assignments and allocation policies as
specified in Table 7.
+---------+-------------+-------------------+
| Type | Description | Allocation Policy |
+---------+-------------+-------------------+
| 128-223 | Unassigned | Expert Review |
+---------+-------------+-------------------+
Table 7: TC Message-Type-specific Message TLV Types
IANA is requested to create a registry for Message-Type-specific
Address Block TLVs for TC messages, in accordance with Section 6.2.1
of [RFC5444], and with initial assignments and allocation policies as
specified in Table 8.
+---------+-------------+-------------------+
| Type | Description | Allocation Policy |
+---------+-------------+-------------------+
| 128-223 | Unassigned | Expert Review |
+---------+-------------+-------------------+
Table 8: TC Message-Type-specific Address Block TLV Types
20.4. Message TLV Types
This specification defines two Message TLV Types, which must be
allocated from the "Message TLV Types" namespace defined in
[RFC5444]. IANA are requested to make allocations in the 8-127 range
for these types. This will create two new Type Extension registries
with assignments as specified in Table 9 and Table 10.
Specifications of these TLVs are in Section 8.1.1 and Section 8.2.1,
respectively. Each of these TLVs MUST NOT be included more than once
in a Message TLV Block.
+-------------+------+-----------+----------------------------------+
| Name | Type | Type | Description |
| | | Extension | |
+-------------+------+-----------+----------------------------------+
| MPR_WILLING | TBD2 | 0 | Specifies the originating |
| | | | router's willingness to act as a |
| | | | relay and to partake in network |
| | | | formation |
| Unassigned | TBD2 | 1-255 | Expert Review |
+-------------+------+-----------+----------------------------------+
Table 9: Message TLV Type assignment: MPR_WILLING
+--------------+------+----------------+----------------------------+
| Name | Type | Type Extension | Description |
+--------------+------+----------------+----------------------------+
| CONT_SEQ_NUM | TBD3 | 0 (COMPLETE) | Specifies a content |
| | | | sequence number for this |
| | | | complete message |
| CONT_SEQ_NUM | TBD3 | 1 (INCOMPLETE) | Specifies a content |
| | | | sequence number for this |
| | | | incomplete message |
| Unassigned | TBD3 | 2-255 | Expert Review |
+--------------+------+----------------+----------------------------+
Table 10: Message TLV Type assignment: CONT_SEQ_NUM
Type extensions indicated as Expert Review SHOULD be allocated as
described in [RFC5444], based on Expert Review as defined in
[RFC5226].
20.5. Address Block TLV Types
This specification defines three Address Block TLV Types, which must
be allocated from the "Address Block TLV Types" namespace defined in
[RFC5444]. IANA are requested to make allocations in the 8-127 range
for these types. This will create three new Type Extension
registries with assignments as specified in Table 11, Table 12 and
Table 13, respectively. Specifications of these TLVs are in
Section 8.1.2 and Section 8.2.2.
+------------+------+-----------+-----------------------------------+
| Name | Type | Type | Description |
| | | Extension | |
+------------+------+-----------+-----------------------------------+
| MPR | TBD4 | 0 | Specifies that a given address is |
| | | | of a router selected as an MPR |
| Unassigned | TBD4 | 1-255 | Expert Review |
+------------+------+-----------+-----------------------------------+
Table 11: Address Block TLV Type assignment: MPR
+---------------+------+-----------+--------------------------------+
| Name | Type | Type | Description |
| | | Extension | |
+---------------+------+-----------+--------------------------------+
| NBR_ADDR_TYPE | TBD5 | 0 | Specifies that a given address |
| | | | is of a neighbor reached via |
| | | | the originating router |
| Unassigned | TBD5 | 1-255 | Expert Review |
+---------------+------+-----------+--------------------------------+
Table 12: Address Block TLV Type assignment: NBR_ADDR_TYPE
The Values which the NBR_ADDR_TYPE Address Block TLV can use are the
following:
o ORIGINATOR := 1;
o ROUTABLE := 2;
o ROUTABLE_ORIG := 3.
+------------+------+-----------+-----------------------------------+
| Name | Type | Type | Description |
| | | extension | |
+------------+------+-----------+-----------------------------------+
| GATEWAY | TBD6 | 0 | Specifies that a given address is |
| | | | reached via a gateway on the |
| | | | originating router |
| Unassigned | TBD6 | 1-255 | Expert Review |
+------------+------+-----------+-----------------------------------+
Table 13: Address Block TLV Type assignment: GATEWAY
Type extensions indicated as Expert Review SHOULD be allocated as
described in [RFC5444], based on Expert Review as defined in
[RFC5226].
21. Contributors 21. Contributors
This specification is the result of the joint efforts of the This specification is the result of the joint efforts of the
following contributors -- listed alphabetically. following contributors -- listed alphabetically.
o Cedric Adjih, INRIA, France, <Cedric.Adjih@inria.fr> o Cedric Adjih, INRIA, France, <Cedric.Adjih@inria.fr>
o Emmanuel Baccelli, INRIA , France, <Emmanuel.Baccelli@inria.fr> o Emmanuel Baccelli, INRIA , France, <Emmanuel.Baccelli@inria.fr>
skipping to change at page 58, line 29 skipping to change at page 68, line 17
<chris.dearlove@baesystems.com> <chris.dearlove@baesystems.com>
o Satoh Hiroki, Hitachi SDL, Japan, <hiroki.satoh.yj@hitachi.com> o Satoh Hiroki, Hitachi SDL, Japan, <hiroki.satoh.yj@hitachi.com>
o Philippe Jacquet, INRIA, France, <Philippe.Jacquet@inria.fr> o Philippe Jacquet, INRIA, France, <Philippe.Jacquet@inria.fr>
o Monden Kazuya, Hitachi SDL, Japan, <kazuya.monden.vw@hitachi.com> o Monden Kazuya, Hitachi SDL, Japan, <kazuya.monden.vw@hitachi.com>
o Kenichi Mase, Niigata University, Japan, <mase@ie.niigata-u.ac.jp> o Kenichi Mase, Niigata University, Japan, <mase@ie.niigata-u.ac.jp>
o Ryuji Wakikawa, KEIO University, Japan, <ryuji@sfc.wide.ad.jp> o Ryuji Wakikawa, Toyota, Japan, <ryuji@sfc.wide.ad.jp>
22. Acknowledgments 22. Acknowledgments
The authors would like to acknowledge the team behind OLSRv1, The authors would like to acknowledge the team behind OLSRv1,
specified in RFC3626, including Anis Laouiti (INT, Paris), Pascale specified in RFC3626, including Anis Laouiti (INT, Paris), Pascale
Minet (INRIA, France), Laurent Viennot (INRIA, France), and Amir Minet (INRIA, France), Laurent Viennot (INRIA, France), and Amir
Qayyum (M.A. Jinnah University, Islamabad) for their contributions. Qayyum (M.A. Jinnah University, Islamabad) for their contributions.
The authors would like to gratefully acknowledge the following people The authors would like to gratefully acknowledge the following people
for intense technical discussions, early reviews and comments on the for intense technical discussions, early reviews and comments on the
specification and its components (listed alphabetically): Khaldoun Al specification and its components (listed alphabetically): Khaldoun Al
Agha (LRI), Song-Yean Cho (LIX), Alan Cullen (BAE Systems), Louise Agha (LRI), Teco Boot (Infinity Networks), Song-Yean Cho (LIX), Alan
Lamont (CRC), Li Li (CRC), Joe Macker (NRL), Richard Ogier (SRI), Cullen (BAE Systems), Louise Lamont (CRC), Li Li (CRC), Joe Macker
Charles E. Perkins (WiChorus), Shubhranshu Singh (Samsung AIT), and (NRL), Richard Ogier (SRI), Charles E. Perkins (WiChorus), Henning
the entire IETF MANET working group. Rogge (FGAN), and the entire IETF MANET working group.
23. References 23. References
23.1. Normative References 23.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", RFC 2119, BCP 14, March 1997. Requirement Levels", RFC 2119, BCP 14, March 1997.
[RFC5148] Clausen, T., Dearlove, C., and B. Adamson, "Jitter [RFC5148] Clausen, T., Dearlove, C., and B. Adamson, "Jitter
considerations in MANETs", RFC 5148, February 2008. considerations in MANETs", RFC 5148, February 2008.
skipping to change at page 60, line 9 skipping to change at page 69, line 46
relaying: An efficient technique for flooding in mobile relaying: An efficient technique for flooding in mobile
wireless networks.", 2001. wireless networks.", 2001.
[FSR] Pei, G., Gerla, M., and T. Chen, "Fisheye state routing [FSR] Pei, G., Gerla, M., and T. Chen, "Fisheye state routing
in mobile ad hoc networks", 2000. in mobile ad hoc networks", 2000.
[FSLS] Santivanez, C., Ramanathan, R., and I. Stavrakakis, [FSLS] Santivanez, C., Ramanathan, R., and I. Stavrakakis,
"Making link-state routing scale for ad hoc networks", "Making link-state routing scale for ad hoc networks",
2000. 2000.
Appendix A. Router Configuration Appendix A. Example Algorithm for Calculating MPRs
OLSRv2 does not make any assumption about router addresses, other
than that each router is assumed to have at least one unique and
routable IP address for each interface that it has which participates
in the MANET.
When applicable, a recommended way of connecting an OLSRv2 network to
an existing IP routing domain is to assign an IP prefix (under the
authority of the routers/gateways connecting the MANET with the
routing domain) exclusively to the OLSRv2 area, and to configure the
gateways statically to advertise routes to that IP sequence to
routers in the existing routing domain.
Appendix B. Example Algorithm for Calculating MPRs
The following specifies an algorithm which MAY be used to select The following specifies an algorithm which MAY be used to select
MPRs. MPRs are calculated per OLSRv2 interface, but then a single MPRs. MPRs are calculated per OLSRv2 interface, but then a single
set of MPRs is formed from the union of the MPRs for all OLSRv2 set of MPRs is formed from the union of the MPRs for all OLSRv2
interfaces. (As noted in Section 14 a router MAY improve on this, by interfaces. (As noted in Section 14 a router MAY improve on this, by
coordination between OLSRv2 interfaces.) A router's MPRs are coordination between OLSRv2 interfaces.) A router's MPRs are
recorded using the element N_mpr in Neighbor Tuples. recorded using the element N_mpr in Neighbor Tuples.
If using this algorithm then the following steps MUST be executed in If using this example algorithm then the following steps MUST be
order for a router to select its MPRs: executed in order for a router to select its MPRs:
1. Set N_mpr := false in all Neighbor Tuples; 1. Set N_mpr := false in all Neighbor Tuples;
2. For each Neighbor Tuple with N_symmetric = true and N_willingness 2. For each Neighbor Tuple with N_symmetric = true and N_willingness
= WILL_ALWAYS, set N_mpr := true; = WILL_ALWAYS, set N_mpr := true;
3. For each OLSRv2 interface of the router, use the algorithm in 3. For each OLSRv2 interface of the router, use the algorithm in
Appendix B.2. Note that this sets N_mpr := true for some Appendix A.2. Note that this sets N_mpr := true for some
Neighbor Tuples, these routers are already selected as MPRs when Neighbor Tuples, these routers are already selected as MPRs when
using the algorithm for following OLSRv2 interfaces. using the algorithm for following OLSRv2 interfaces.
4. OPTIONALLY, consider each selected MPR in turn, and if the set of 4. OPTIONALLY, consider each selected MPR in turn, and if the set of
selected MPRs without that router still satisfies the necessary selected MPRs without that router still satisfies the necessary
conditions, for all OLSRv2 interfaces, then that router MAY be conditions, for all OLSRv2 interfaces, then that router MAY be
removed from the set of MPRs. This process MAY be repeated until removed from the set of MPRs. This process MAY be repeated until
no MPRs are removed. Routers MAY be considered in order of no MPRs are removed. Routers MAY be considered in order of
increasing N_willingness. increasing N_willingness.
Symmetric 1-hop neighbor routers with N_willingness = WILL_NEVER MUST Note that only symmetric strict 2-hop neighbors are considered, thus:
NOT be selected as MPRs, and MUST be ignored in the following
algorithm, as MUST be symmetric 2-hop neighbor routers which are also
symmetric 1-hop neighbor routers (i.e. when considering 2-Hop Tuples,
ignore any 2-Hop Tuples whose N2_2hop_addr is in the
N_neighbor_addr_list of any Neighbor Tuple, or whose
N2_neighbor_iface_addr_list is included in the N_neighbor_addr_list
of any Neighbor Tuple with N_willingness = WILL_NEVER).
B.1. Terminology o Symmetric 1-hop neighbor routers with N_willingness = WILL_NEVER
MUST NOT be selected as MPRs, and MUST be ignored in the following
algorithm (and hence also ignore any 2-Hop Tuples whose
N2_neighbor_iface_addr_list is included in the
N_neighbor_addr_list of any such Neighbor Tuple).
o Symmetric 2-hop neighbor routers which are also symmetric 1-hop
neighbor routers MUST be ignored in the following algorithm (i.e.
ignore any 2-Hop Tuples whose N2_2hop_addr is in the
N_neighbor_addr_list of any Neighbor Tuple).
A.1. Terminology
The following terminology will be used when selecting MPRs for the The following terminology will be used when selecting MPRs for the
OLSRv2 interface I: OLSRv2 interface I:
N(I) - The set of symmetric 1-hop neighbors which have a symmetric N(I) - The set of symmetric 1-hop neighbors which have a symmetric
link to I. link to I.
N2(I) - The set of addresses of interfaces of a router with a N2(I) - The set of addresses of interfaces of a router with a
symmetric link to a router in N(I); this MAY be restricted to symmetric link to a router in N(I); this MAY be restricted to
considering only information received over I (in which case N2(I) considering only information received over I (in which case N2(I)
skipping to change at page 61, line 40 skipping to change at page 71, line 19
N2_neighbor_iface_addr_list is contained in the set of interface N2_neighbor_iface_addr_list is contained in the set of interface
addresses of Y). addresses of Y).
D(Y, I) - For a router Y in N(I), the number of addresses in N2(I) D(Y, I) - For a router Y in N(I), the number of addresses in N2(I)
which are connected to I via Y. which are connected to I via Y.
R(Y, I): - For a router Y in N(I), the number of addresses in N2(I) R(Y, I): - For a router Y in N(I), the number of addresses in N2(I)
which are connected to I via Y, but are not connected to I via any which are connected to I via Y, but are not connected to I via any
router which has already been selected as an MPR. router which has already been selected as an MPR.
B.2. MPR Selection Algorithm for each OLSRv2 Interface A.2. MPR Selection Algorithm for each OLSRv2 Interface
When selecting MPRs for the OLSRv2 interface I: When selecting MPRs for the OLSRv2 interface I:
1. For each address A in N2(I) for which there is only one router Y 1. For each address A in N2(I) for which there is only one router Y
in N(I) such that A is connected to I via Y, select that router Y in N(I) such that A is connected to I via Y, select that router Y
as an MPR (i.e. set N_mpr := true in the Neighbor Tuple as an MPR (i.e. set N_mpr := true in the Neighbor Tuple
corresponding to Y). corresponding to Y).
2. While there exists any router Y in N(I) with R(Y, I) > 0: 2. While there exists any router Y in N(I) with R(Y, I) > 0:
skipping to change at page 62, line 22 skipping to change at page 71, line 47
+ greatest D(Y, I), THEN; + greatest D(Y, I), THEN;
+ N_mpr_selector is equal to true, if possible, THEN; + N_mpr_selector is equal to true, if possible, THEN;
+ any choice. + any choice.
2. Select Y as an MPR (i.e. set N_mpr := true in the Neighbor 2. Select Y as an MPR (i.e. set N_mpr := true in the Neighbor
Tuple corresponding to Y). Tuple corresponding to Y).
Appendix C. Example Algorithm for Calculating the Routing Set Appendix B. Example Algorithm for Calculating the Routing Set
The following procedure is given as an example for calculating the The following procedure is given as an example for calculating the
Routing Set using a variation of Dijkstra's algorithm. First all Routing Set using a variation of Dijkstra's algorithm. First all
Routing Tuples are removed, and then the procedures in the following Routing Tuples are removed, and then, using the selections and
sections are applied in turn. definitions in Appendix B.1, the procedures in the following sections
(each considered a "stage" of the processing) are applied in turn.
C.1. Add Local Symmetric Links B.1. Local Interfaces and Neighbors
1. For each Local Interface Tuple: The following selections and definitions are made:
1. Select an address (the "local address") in 1. For each Local Interface Tuple, select an address from its
I_local_iface_addr_list. I_local_iface_addr_list, this is defined as the selected address
for this Local Interface Tuple.
2. For each Link Tuple for this local interface with L_status = 2. For each Link Tuple, the selected address of its corresponding
SYMMETRIC: Local Interface Tuple is defined as the selected local address
for this Local Interface Tuple.
1. For each address (the "current address") in 3. For each Neighbor Tuple with N_symmetric = true, the selected
L_neighbor_iface_addr_list, if there is no Routing Tuple local address is defined as the selected local address of the
with R_dest_addr = current address, then add a Routing selected Link Tuple for that Neighbor Tuple.
Tuple with:
- R_dest_addr := current address; 4. For each address (N_orig_addr or in N_neighbor_addr_list, the
"neighbor address") from a Neighbor Tuple with N_symmetric =
true, select a Link Tuple with L_status = SYMMETRIC whose
corresponding Neighbor Tuple is this Neighbor Tuple and where, if
possible, L_neighbor_iface_addr_list contains the neighbor
address. This is defined as the selected Link Tuple for that
neighbor address.
- R_next_iface_addr := current address; 5. For each address (N_orig_addr or in N_neighbor_addr_list, the
"neighbor address") from a Neighbor Tuple with N_symmetric =
true, a selected address from the L_neighbor_iface_addr_list of
the selected Link Tuple for the neighbor address, if possible
equal to the neighbor address, is defined as the selected link
address for that neighbor address.
- R_dist := 1; 6. Routing Tuple preference is decided by preference for
corresponding Neighbor Tuples in this order:
- R_local_iface_addr := local address. * For greater N_willingness.
2. For each Neighbor Tuple whose N_neighbor_addr_list contains the * For N_mpr_selector = true over N_mpr_selector = false.
R_dest_addr of a Routing Tuple (the "previous Tuple"):
1. For each address (the "current address") in B.2. Add Neighbor Routers
N_neighbor_addr_list, if there is no Routing Tuple with
R_dest_addr = current address, then add a Routing Tuple with:
+ R_dest_addr := current address; The following procedure is executed once.
+ R_next_iface_addr := R_dest_addr of the previous Tuple; 1. For each Neighbor Tuple with N_symmetric = true, add a Routing
Tuple with:
+ R_dist := 1; * R_dest_addr := N_orig_addr;
+ R_local_iface_addr := R_local_iface_addr of the previous * R_next_iface_addr := selected link address;
Tuple.
C.2. Add Remote Symmetric Links * R_local_iface_addr := selected local address;
The following procedure, which adds Routing Tuples for destination * R_dist := 1.
routers h+1 hops away, MUST be executed for each value of h, starting
B.3. Add Remote Routers
The following procedure is executed for each value of h, starting
with h := 1 and incrementing by 1 for each iteration. The execution with h := 1 and incrementing by 1 for each iteration. The execution
MUST stop if no new Routing Tuples are added in an iteration. MUST stop if no new Routing Tuples are added in an iteration.
1. For each Topology Tuple, if: 1. For each Router Topology Tuple, if:
* T_dest_addr is not equal to R_dest_addr of any Routing Tuple, * TR_to_orig_addr is not equal to the R_dest_addr of any Routing
AND; Tuple added in an earlier stage, AND;
* for the Advertising Remote Router Tuple with AR_orig_addr = * TR_from_orig_addr is equal to the R_dest_addr of a Routing
T_orig_addr, there is an address in the AR_addr_list which is Tuple with R_dist = h (the "previous Routing Tuple"),
equal to the R_dest_addr of a Routing Tuple (the "previous
Routing Tuple") whose R_dist = h
then add a new Routing Tuple, with: then add a new Routing Tuple, with:
* R_dest_addr := T_dest_addr; * R_dest_addr := TR_to_orig_addr;
* R_next_iface_addr := R_next_iface_addr of the previous Routing * R_next_iface_addr := R_next_iface_addr of the previous Routing
Tuple; Tuple;
* R_dist := h+1;
* R_local_iface_addr := R_local_iface_addr of the previous * R_local_iface_addr := R_local_iface_addr of the previous
Routing Tuple. Routing Tuple;
More than one Topology Tuple may be usable to select the next hop * R_dist := h+1.
R_next_iface_addr for reaching the address R_dest_addr. Ties
should be broken such that routers with greater willingness are
preferred, and between routers of equal willingness, MPR
selectors are preferred over non-MPR selectors.
2. After the above iteration has completed, if h = 1, for each 2-Hop There may be more than one possible Routing Tuple that may be
Neighbor Tuple where: added for an R_dest_addr in this stage. If so, then, for each
such R_dest_addr, a Routing Tuple which is preferred SHOULD be
added.
* N2_2hop_addr is not equal to R_dest_addr of any Routing Tuple, B.4. Add Neighbor Addresses
AND;
* The Neighbor Tuple whose N_neighbor_addr_list contains The following procedure is executed once.
N2_neighbor_iface_addr_list has N_willingness not equal to
WILL_NEVER
select a Routing Tuple (the "previous Routing Tuple") whose 1. For each Neighbor Tuple with N_symmetric = true:
R_dest_addr is contained in N2_neighbor_iface_addr_list, and add
a new Routing Tuple with:
* R_dest_addr := N2_2hop_addr; 1. For each address (the "current address") in
N_neighbor_addr_list, if the current address is not equal to
the R_dest_addr of any Routing Tuple, then add a new Routing
Tuple, with:
+ R_dest_addr := current address;
+ R_next_iface_addr := selected link address;
+ R_local_iface_addr := selected local address;
+ R_dist := 1.
B.5. Add Remote Routable Addresses
The following procedure is executed once.
1. For each Routable Address Topology Tuple, if:
* TA_dest_addr is not equal to the R_dest_addr of any Routing
Tuple added in an earlier stage, AND;
* TR_from_orig_addr is equal to the R_dest_addr of a Routing
Tuple (the "previous Routing Tuple"),
then add a new Routing Tuple, with:
* R_dest_addr := TA_dest_addr;
* R_next_iface_addr := R_next_iface_addr of the previous Routing * R_next_iface_addr := R_next_iface_addr of the previous Routing
Tuple; Tuple;
* R_dist := 2; * R_local_iface_addr := R_local_iface_addr of the previous
Routing Tuple;
* R_dist := R_dist of the previous Routing Tuple + 1.
There may be more than one possible Routing Tuple that may be
added for an R_dest_addr in this stage. If so, then, for each
such R_dest_addr, a Routing Tuple which is preferred SHOULD be
added.
B.6. Add Attached Networks
The following procedure is executed once.
1. For each Attached Network Tuple, if:
* AN_orig_addr is not equal to the R_dest_addr of any Routing
Tuple added in an earlier stage, AND;
* AN_orig_addr is equal to the R_dest_addr of a Routing Tuple
(the "previous Routing Tuple),
then add a new Routing Tuple, with:
* R_dest_addr := AN_net_addr;
* R_next_iface_addr := R_next_iface_addr of the previous Routing
Tuple;
* R_local_iface_addr := R_local_iface_addr of the previous * R_local_iface_addr := R_local_iface_addr of the previous
Routing Tuple. Routing Tuple;
More than one 2-Hop Neighbor Tuple may be usable to select the * R_dist := R_dist of the previous Routing Tuple + AN_dist.
next hop R_next_iface_addr for reaching the address R_dest_addr.
Ties should be broken such that routers with greater willingness
are preferred, and between routers of equal willingness, MPR
selectors are preferred over non-MPR selectors.
C.3. Add Attached Networks There may be more than one possible Routing Tuple that may be
added for an R_dest_addr in this stage. If so, then, for each
such R_dest_addr, a Routing Tuple with minimum R_dist MUST be
selected, otherwise a Routing Tuple which is preferred SHOULD be
added.
1. For each Attached Network Tuple, if for the Advertising Remote B.7. Add 2-Hop Neighbors
Router Tuple with AR_orig_addr = AN_orig_addr, there is an
address in the AR_addr_list which is equal to the R_dest_addr of
a Routing Tuple (the "previous Routing Tuple"), then:
1. If there is no Routing Tuple with R_dest_addr = AN_net_addr, The following procedure is executed once.
then add a new Routing Tuple with:
+ R_dest_addr := AN_net_addr; 1. For each 2-Hop Tuple, if:
+ R_next_iface_addr := R_next_iface_addr of the previous * N2_2hop_addr is a routable address, AND;
Routing Tuple;
+ R_dist := (R_dist of the previous Routing Tuple) + * N2_2hop_addr is not equal to the R_dest_addr of any Routing
AN_dist; Tuple added in an earlier stage,
+ R_local_iface_addr := R_local_iface_addr of the previous then define the "previous Routing Tuple" as that with R_dest_addr
Routing Tuple. = N_orig_addr of the corresponding Neighbor Tuple, and add a new
Routing Tuple, with:
2. Otherwise if the Routing Tuple with R_dest_addr = AN_net_addr * R_dest_addr := N2_2hop_addr;
(the "current Routing Tuple") has R_dist > (R_dist of the
previous Routing Tuple) + AN_dist, then modify the current
Routing Tuple by:
+ R_next_iface_addr := R_next_iface_addr of the previous * R_next_iface_addr := R_next_iface_addr of the previous Routing
Routing Tuple; Tuple;
+ R_dist := (R_dist of the previous Routing Tuple) + * R_local_iface_addr := R_local_iface_addr of the previous
AN_dist; Routing Tuple;
+ R_local_iface_addr := R_local_iface_addr of the previous * R_dist := 2.
Routing Tuple.
Appendix D. Example Message Layout There may be more than one possible Routing Tuple that may be
added for an R_dest_addr in this stage. If so, then, for each
such R_dest_addr, a Routing Tuple which is preferred SHOULD be
added.
Appendix C. Example Message Layout
An example TC message is as follows. The message has full Message An example TC message is as follows. The message has full Message
Header (four bit Flags field value is 15). Its four bit Message Header (four bit Flags field value is 15). Its four bit Message
Address Length field has value 3 and hence addresses in the message Address Length field has value 3 and hence addresses in the message
have length four octets, here being IPv4 addresses. The overall have length four octets, here being IPv4 addresses. The overall
message length is 65 octets. message length is 57 octets.
The message has a Message TLV Block with content length 13 octets The message has a Message TLV Block with content length 13 octets
containing three TLVs. The first two TLVs are interval and validity containing three TLVs. The first two TLVs are interval and validity
times for the message. The third TLV is the content sequence number times for the message. The third TLV is the content sequence number
TLV used to carry the 2 octet ANSN, and (with default type extension TLV used to carry the 2 octet ANSN, and (with default type extension
zero, i.e. COMPLETE) indicating that the TC message is complete. zero, i.e. COMPLETE) indicating that the TC message is complete.
Each TLV uses a TLV with Flags octet value 16, indicating that it has Each TLV uses a TLV with Flags octet value 16, indicating that it has
a Value, but no type extension or start and stop indexes. The first a Value, but no type extension or start and stop indexes. The first
two TLVs have a Value Length of 1 octet, the last has a Value Length two TLVs have a Value Length of 1 octet, the last has a Value Length
of 2 octets. of 2 octets.
The message has two Address Blocks. The first Address Block contains The message has two Address Blocks. (This is not necessary, the
6 addresses, with Flags octet value 128, hence with a Head section, information could be conveyed using a single Address Block, the use
(with length 2 octets) but no Tail section, and hence Mid sections of two Address Blocks, which is also allowed, is illustrative only.)
with length two octets. The following TLV Block (content length 6 The first Address Block contains 3 addresses, with Flags octet value
octets) contains a single LOCAL_IF TLV (Flags octet value 48) 128, hence with a Head section, (with length 2 octets) but no Tail
indicating that the first three addresses (indexes 0 to 2) are section, and hence Mid sections with length two octets. The
associated with the Value (with Value Length 1 octet) UNSPEC_IF, i.e. following TLV Block (content length 6 octets) contains a single
they are the originating router's local addresses. The remaining NBR_ADDR_TYPE TLV (Flags octet value 16, includes a Value but no
three addresses have no associated TLV, they are the addresses of indexes) indicating that these addresses are associated with the
advertised neighbors. Value (with Value Length 1 octet) ROUTABLE_ORIG, i.e. they are
originator addresses of advertised neighbors that are also routable
addresses.
The second Address Block contains 1 address, with Flags octet 176 The second Address Block contains 1 address, with Flags octet 176
indicating that there is a Head section (with length 2 octets), that indicating that there is a Head section (with length 2 octets), that
the Tail section (length 2 octets) consists of zero valued octets the Tail section (length 2 octets) consists of zero valued octets
(not included), and that there is a single prefix length, which is (not included), and that there is a single prefix length, which is
16. The network address is thus Head.0.0/16. The following TLV 16. The network address is thus Head.0.0/16. The following TLV
Block (content length 8 octets) includes one TLV that indicates that Block (content length 8 octets) includes one TLV that indicates that
the originating router is a gateway to this network, at a given the originating router is a gateway to this network, at a given
number of hops distance (Value Length 1 octet). The TLV Flags octet number of hops distance (Value Length 1 octet). The TLV Flags octet
value of 16 indicates that no indexes are needed. value of 16 again indicates that a Value, but no indexes are needed.
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TC |1 1 1 1 0 0 1 1|0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1| | TC |1 1 1 1 0 0 1 1|0 0 0 0 0 0 0 0 0 0 1 1 1 0 0 1|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Originator Address | | Originator Address |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Hop Limit | Hop Count | Message Sequence Number | | Hop Limit | Hop Count | Message Sequence Number |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 1| INTERVAL_TIME |0 0 0 1 0 0 0 0| |0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 1| INTERVAL_TIME |0 0 0 1 0 0 0 0|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0 0 0 0 0 1| Value | VALIDITY_TIME |0 0 0 1 0 0 0 0| |0 0 0 0 0 0 0 1| Value | VALIDITY_TIME |0 0 0 1 0 0 0 0|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0 0 0 0 0 1| Value | CONT_SEQ_NUM |0 0 0 1 0 0 0 0| |0 0 0 0 0 0 0 1| Value | CONT_SEQ_NUM |0 0 0 1 0 0 0 0|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0 0 0 0 1 0| Value (ANSN) |0 0 0 0 0 1 1 0| |0 0 0 0 0 0 1 0| Value (ANSN) |0 0 0 0 0 0 1 1|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|1 0 0 0 0 0 0 0|0 0 0 0 0 0 1 0| Head | |1 0 0 0 0 0 0 0|0 0 0 0 0 0 1 0| Head |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Mid | Mid | | Mid | Mid |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Mid | Mid | | Mid |0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Mid | Mid |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0| LOCAL_IF |0 0 1 1 0 0 0 0|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0 0 0 0 0 0|0 0 0 0 0 0 1 0|0 0 0 0 0 0 0 1| UNSPEC_IF | | NBR_ADDR_TYPE |0 0 0 1 0 0 0 0|0 0 0 0 0 0 0 1| ROUTABLE_ORIG |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0 0 0 0 0 1|1 0 1 1 0 0 0 0|0 0 0 0 0 0 1 0| Head | |0 0 0 0 0 0 0 1|1 0 1 1 0 0 0 0|0 0 0 0 0 0 1 0| Head |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Head (cont) |0 0 0 0 0 0 1 0|0 0 0 1 0 0 0 0|0 0 0 0 0 0 0 0| | Head (cont) |0 0 0 0 0 0 1 0|0 0 0 1 0 0 0 0|0 0 0 0 0 0 0 0|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0 0 0 0 0 1 0 0| GATEWAY |0 0 0 1 0 0 0 0|0 0 0 0 0 0 0 1| |0 0 0 0 0 1 0 0| GATEWAY |0 0 0 1 0 0 0 0|0 0 0 0 0 0 0 1|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Number Hops | | Number Hops |
+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+
Appendix E. Constraints Appendix D. Constraints
Any process which updates the Local Information Base, the Any process which updates the Local Information Base, the
Neighborhood Information Base or the Topology Information Base MUST Neighborhood Information Base or the Topology Information Base MUST
ensure that all constraints specified in this appendix are ensure that all constraints specified in this appendix are
maintained, as well as those specified in [NHDP]. maintained, as well as those specified in [NHDP].
In each Originator Tuple: In each Originator Tuple:
o O_orig_addr MUST NOT equal any other O_orig_addr. o O_orig_addr MUST NOT equal any other O_orig_addr.
o O_orig_addr MUST NOT equal this router's originator address. o O_orig_addr MUST NOT equal this router's originator address.
In each Local Attached Network Tuple: In each Local Attached Network Tuple:
o AL_net_addr MUST NOT equal any other AL_net_addr. o AL_net_addr MUST NOT equal any other AL_net_addr.
o AL_net_addr MUST NOT be in the I_local_iface_addr_list of any o AL_net_addr MUST NOT be in the I_local_iface_addr_list of any
Local Interface Tuple or be equal to the IR_local_iface_addr of Local Interface Tuple or equal the IR_local_iface_addr of any
any Removed Interface Address Tuple. Removed Interface Address Tuple.
o AL_net_addr MUST not equal this router's originator address, or
equal the O_orig_addr in any Originator Tuple.
o AL_dist MUST NOT be less than zero. o AL_dist MUST NOT be less than zero.
In each Link Tuple: In each Link Tuple:
o L_neighbor_iface_addr_list MUST NOT contain the AL_net_addr of any o L_neighbor_iface_addr_list MUST NOT contain the AL_net_addr of any
Local Attached Network Tuple. Local Attached Network Tuple.
o If L_status = SYMMETRIC and the Neighbor Tuple whose
N_neighbor_addr_list contains L_neighbor_iface_addr_list has
N_mpr_selector = true, then, for each address in this
L_neighbor_iface_addr_list, there MUST be an equal
RY_neighbor_iface_addr in the Relay Set associated with the same
OLSRv2 interface.
In each Neighbor Tuple: In each Neighbor Tuple:
o N_neighbor_addr_list MUST NOT contain the AL_net_addr of any Local o N_orig_addr MUST NOT be changed to unknown.
Attached Network Tuple.
o N_orig_addr MUST NOT equal this router's originator address, or
equal O_orig_addr in any Originator Tuple.
o N_orig_addr MUST NOT equal the AL_net_addr in any Local Attached
Network Tuple.
o N_neighbor_addr_list MUST NOT contain this router's originator
address, the O_orig_addr in any Originator Tuple, or the
AL_net_addr in any Local Attached Network Tuple.
o If N_orig_addr = unknown, then N_willingness = WILL_NEVER, N_mpr =
false, N_mpr_selector = false, and N_advertised = false.
o If N_willingness MUST be in the range from WILL_NEVER to o If N_willingness MUST be in the range from WILL_NEVER to
WILL_ALWAYS, inclusive. WILL_ALWAYS, inclusive.
o If N_mpr = true, then N_symmetric MUST be true and N_willingness o If N_mpr = true, then N_symmetric MUST be true and N_willingness
MUST NOT equal WILL_NEVER. MUST NOT equal WILL_NEVER.
o If N_symmetric = true and N_mpr = false, then N_willingness MUST o If N_symmetric = true and N_mpr = false, then N_willingness MUST
NOT equal WILL_ALWAYS. NOT equal WILL_ALWAYS.
o If N_mpr_selector = true, then N_symmetric MUST be true. o If N_mpr_selector = true, then N_symmetric MUST be true and
N_advertised MUST be true.
o If N_mpr_selector = true, then, for each address in this o If N_advertised = true, then N_symmetric MUST be true.
N_neighbor_addr_list, there MUST be an equal A_neighbor_addr in
the Advertised Neighbor Set.
In each Lost Neighbor Tuple: In each Lost Neighbor Tuple:
o NL_neighbor_addr MUST NOT equal the AL_net_addr of any Local o NL_neighbor_addr MUST NOT equal this router's originator address,
Attached Network Tuple. equal the O_orig_addr in any Originator Tuple, or equal the
AL_net_addr in any Local Attached Network Tuple.
In each 2-Hop Tuple: In each 2-Hop Tuple:
o N2_2hop_addr MUST NOT equal the AL_net_addr of any Local Attached o N2_2hop_addr MUST NOT equal this router's originator address,
Network Tuple. equal the O_orig_addr in any Originator Tuple, or equal the
AL_net_addr in any Local Attached Network Tuple.
In each Received Tuple: In each Advertising Remote Router Tuple:
o RX_orig_addr MUST NOT equal this router's originator address or o AR_orig_addr MUST NOT be in the I_local_iface_addr_list in any
any O_orig_addr. Local Interface Tuple or equal the IR_local_iface_addr in any
Removed Interface Address Tuple.
o Each ordered triple (RX_type, RX_orig_addr, RX_seq_number) MUST o AR_orig_addr MUST NOT equal this router's originator address or
NOT equal the corresponding triple in any other Received Tuple in equal the O_orig_addr in any Originator Tuple.
the same Received Set.
In each Processed Tuple: o AR_orig_addr MUST NOT equal the AL_net_addr in any Local Attached
Network Tuple.
o P_orig_addr MUST NOT equal this router's originator address or any o AR_orig_addr MUST NOT equal the AR_orig_addr in any other
O_orig_addr. Advertising Remote Router Tuple.
o Each ordered triple (P_type, P_orig_addr, P_seq_number) MUST NOT In each Router Topology Tuple:
equal the corresponding triple in any other Processed Tuple.
In each Forwarded Tuple: o There MUST be an Advertising Remote Router Tuple with AR_orig_addr
= TR_from_orig_addr.
o F_orig_addr MUST NOT equal this router's originator address or any o TR_to_orig_addr MUST NOT be in the I_local_iface_addr_list in any
O_orig_addr. Local Interface Tuple or equal the IR_local_iface_addr in any
Removed Interface Address Tuple.
o Each ordered triple (F_type, F_orig_addr, F_seq_number) MUST NOT o TR_to_orig_addr MUST NOT equal this router's originator address or
equal the corresponding triple in any other Forwarded Tuple. equal the O_orig_addr in any Originator Tuple.
In each Relay Tuple: o TR_to_orig_addr MUST NOT equal the AL_net_addr in any Local
Attached Network Tuple.
o RY_neighbor_iface_addr MUST NOT equal the RY_neighbor_iface_addr o The ordered pair (TR_from_orig_addr, TR_to_orig_addr) MUST NOT
in any other Relay Tuple in the same Relay Set. equal the corresponding pair for any other Router Topology Tuple.
o RY_neighbor_iface_addr MUST be in the L_neighbor_iface_addr_list o TR_seq_number MUST NOT be greater than AR_seq_number in the
of a Link Tuple with L_status = SYMMETRIC. Advertising Remote Router Tuple with AR_orig_addr =
TR_from_orig_addr.
In the Advertised Neighbor Set: In each Routable Address Topology Tuple:
o Each A_neighbor_addr MUST NOT equal any other A_neighbor_addr. o There MUST be an Advertising Remote Router Tuple with AR_orig_addr
= TA_from_orig_addr.
o Each A_neighbor_addr MUST be in the N_neighbor_addr_list of a o TA_dest_addr MUST be routable.
Neighbor Tuple with N_symmetric = true.
In each Advertising Remote Router Tuple: o TA_dest_addr MUST NOT be in the I_local_iface_addr_list in any
Local Interface Tuple or equal the IR_local_iface_addr in any
Removed Interface Address Tuple.
o AR_orig_addr MUST NOT equal this router's originator address or o TA_dest_addr MUST NOT equal this router's originator address or
any O_orig_addr. equal the O_orig_addr in any Originator Tuple.
o AR_orig_addr MUST NOT equal the AR_orig_addr in any other ANSN o TA_dest_addr MUST NOT equal the AL_net_addr in any Local Attached
History Tuple. Network Tuple.
o AR_addr_list MUST NOT be empty. o The ordered pair (TA_from_orig_addr, TA_dest_addr) MUST NOT equal
the corresponding pair for any other Attached Network Tuple.
o AR_addr_list MUST NOT contain any duplicated addresses. o TA_seq_number MUST NOT be greater than AR_seq_number in the
Advertising Remote Router Tuple with AR_orig_addr =
TA_from_orig_addr.
o AR_addr_list MUST NOT contain any address which is in the In each Attached Network Tuple:
I_local_iface_addr_list of any Local Interface Tuple or be equal
to the IR_local_iface_addr of any Removed Interface Address Tuple.
o AR_addr_list MUST NOT contain any address which is the AL_net_addr o There MUST be an Advertising Remote Router Tuple with AR_orig_addr
of any Local Attached Network Tuple. = AN_orig_addr.
In each Topology Tuple: o AN_net_addr MUST NOT be in the I_local_iface_addr_list in any
Local Interface Tuple or equal the IR_local_iface_addr in any
Removed Interface Address Tuple.
o T_dest_addr MUST NOT be in the I_local_iface_addr_list of any o AN_net_addr MUST NOT equal this router's originator address or
Local Interface Tuple or be equal to the IR_local_iface_addr of equal the O_orig_addr in any Originator Tuple.
any Removed Interface Address Tuple.
o T_dest_addr MUST NOT equal the AL_net_addr of any Local Attached o AN_net_addr MUST NOT equal the AL_net_addr in any Local Attached
Network Tuple. Network Tuple.
o There MUST be an Advertising Remote Router Tuple with AR_orig_addr o The ordered pair (AN_orig_addr, AN_net_addr) MUST NOT equal the
= T_orig_addr. corresponding pair for any other Attached Network Tuple.
o T_dest_addr MUST NOT be in the AR_addr_list of the Advertising o AN_seq_number MUST NOT be greater than AR_seq_number in the
Remote Router Tuple with AR_orig_addr = T_orig_addr. Advertising Remote Router Tuple with AR_orig_addr = AN_orig_addr.
o T_seq_number MUST NOT be greater than AR_seq_number of the o AN_dist MUST NOT be less than zero.
Advertising Remote Router Tuple with AR_orig_addr = T_orig_addr.
o The ordered pair (T_dest_addr, T_orig_addr) MUST NOT equal the In each Received Tuple:
corresponding pair in any other Topology Tuple.
In each Attached Network Tuple: o RX_orig_addr MUST NOT equal this router's originator address or
the O_orig_addr in any Originator Tuple.
o AN_net_addr MUST NOT be in the I_local_iface_addr_list of any o Each ordered triple (RX_type, RX_orig_addr, RX_seq_number) MUST
Local Interface Tuple or be equal to the IR_local_iface_addr of NOT equal the corresponding triple for any other Received Tuple in
any Removed Interface Address Tuple. the same Received Set.
o AN_net_addr MUST NOT equal the AL_net_addr of any Local Attached In each Processed Tuple:
Network Tuple.
o There MUST be an Advertising Remote Router Tuple with AR_orig_addr o P_orig_addr MUST NOT equal this router's originator address or
= AN_orig_addr. equal the O_orig_addr in any Originator Tuple.
o AN_seq_number MUST NOT be greater than AR_seq_number of the o Each ordered triple (P_type, P_orig_addr, P_seq_number) MUST NOT
Advertising Remote Router Tuple with AR_orig_addr = AN_orig_addr. equal the corresponding triple for any other Processed Tuple.
o AN_dist MUST NOT be less than zero. In each Forwarded Tuple:
o The ordered pair (AN_net_addr, AN_orig_addr) MUST NOT equal the o F_orig_addr MUST NOT equal this router's originator address or
corresponding pair in any other Attached Network Tuple. equal the O_orig_addr in any Originator Tuple.
Appendix F. Flow and Congestion Control o Each ordered triple (F_type, F_orig_addr, F_seq_number) MUST NOT
equal the corresponding triple for any other Forwarded Tuple.
Due to its proactive nature, the OLSRv2 protocol has a natural Appendix E. Flow and Congestion Control
control over the flow of its control traffic. Routers transmit
control messages at predetermined rates specified and bounded by
message intervals.
OLSRv2 employs [NHDP] for local signaling, embedding MPR selection Due to its proactive nature, this protocol has a natural control over
advertisement through a simple Address Block TLV, and router the flow of its control traffic. Routers transmit control messages
willingness advertisement (if any) as a single Message TLV. OLSRv2 at predetermined rates specified and bounded by message intervals.
local signaling, therefore, shares the characteristics and
This protocol employs [NHDP] for local signaling, embedding MPR
selection advertisement through a simple Address Block TLV, and
router willingness advertisement (if any) as a single Message TLV.
Local signaling, therefore, shares the characteristics and
constraints of [NHDP]. constraints of [NHDP].
Furthermore, MPR flooding greatly reduces signaling overhead from Furthermore, the use of MPRs can greatly reduce the signaling
from link state information dissemination in two ways. First, the overhead from link state information dissemination in two ways,
amount of link state information for a router to declare is reduced attaining both flooding reduction and topology reduction. First,
to only contain that router's MPR selectors. This reduces the size using MPR flooding, the cost of distributing link state information
of a link state declaration as compared to declaring full link state throughout the network is reduced, as compared to when using classic
information. In particular some routers may not need to declare any flooding, since only MPRs need to forward link state declaration
such information. Second, using MPR flooding, the cost of messages. Second, the amount of link state information for a router
distributing link state information throughout the network is greatly to declare is reduced to need only contain that router's MPR
reduced, as compared to when using classic flooding, since only MPRs selectors. This reduces the size of a link state declaration as
need to forward link state declaration messages. In dense networks, compared to declaring full link state information. In particular
the reduction of control traffic can be of several orders of some routers may not need to declare any such information. In dense
magnitude compared to routing protocols using classical flooding networks, the reduction of control traffic can be of several orders
of magnitude compared to routing protocols using classical flooding
[MPR]. This feature naturally provides more bandwidth for useful [MPR]. This feature naturally provides more bandwidth for useful
data traffic and pushes further the frontier of congestion. data traffic and pushes further the frontier of congestion.
Since the control traffic is continuous and periodic, it keeps the Since the control traffic is continuous and periodic, it keeps the
quality of the links used in routing more stable. However, using quality of the links used in routing more stable. However, using
certain OLSRv2 options, some control messages (HELLO messages or TC some options, some control messages (HELLO messages or TC messages)
messages) may be intentionally sent in advance of their deadline in may be intentionally sent in advance of their deadline in order to
order to increase the responsiveness of the protocol to topology increase the responsiveness of the protocol to topology changes.
changes. This may cause a small, temporary, and local increase of This may cause a small, temporary, and local increase of control
control traffic, however this is at all times bounded by the use of traffic, however this is at all times bounded by the use of minimum
minimum message intervals. message intervals.
Authors' Addresses Authors' Addresses
Thomas Heide Clausen Thomas Heide Clausen
LIX, Ecole Polytechnique LIX, Ecole Polytechnique
Phone: +33 6 6058 9349 Phone: +33 6 6058 9349
EMail: T.Clausen@computer.org EMail: T.Clausen@computer.org
URI: http://www.ThomasClausen.org/ URI: http://www.ThomasClausen.org/
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