Mobile Ad hoc Networking (MANET)                              T. Clausen
Internet-Draft                                  LIX, Ecole Polytechnique
Intended status: Standards Track                             C. Dearlove
Expires: January 14, March 29, 2010                                  BAE Systems ATC
                                                              P. Jacquet
                                                 Project Hipercom, INRIA
                                                  The OLSRv2 Design Team
                                                     MANET Working Group
                                                           July 13,
                                                      September 25, 2009

          The Optimized Link State Routing Protocol version 2
                       draft-ietf-manet-olsrv2-09
                       draft-ietf-manet-olsrv2-10

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Abstract

   This document describes version 2 of the Optimized Link State Routing
   (OLSRv2) protocol for Mobile Ad hoc NETworks (MANETs).

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  5
   2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . . .  6
   3.  Applicability Statement  . . . . . . . . . . . . . . . . . . .  7  8
   4.  Protocol Overview and Functioning  . . . . . . . . . . . . . .  8  9
     4.1.  Overview . . . . . . . . . . . . . . . . . . . . . . . . .  9
     4.2.  Routers and Interfaces . . . . . . . . . . . . . . . . . . 10
     4.2. 11
     4.3.  Information Base Overview  . . . . . . . . . . . . . . . . 11
       4.2.1. 12
       4.3.1.  Local Information Base . . . . . . . . . . . . . . . . 11
       4.2.2. 12
       4.3.2.  Interface Information Bases  . . . . . . . . . . . . . 11
       4.2.3. 12
       4.3.3.  Neighbor Information Base  . . . . . . . . . . . . . . 11
       4.2.4. 13
       4.3.4.  Topology Information Base  . . . . . . . . . . . . . . 12
       4.2.5.  Processing and Forwarding 13
       4.3.5.  Received Message Information Base  . . . . . . 13
     4.3. . . . . 14
     4.4.  Signaling Overview . . . . . . . . . . . . . . . . . . . . 13 15
     4.5.  Routing Set  . . . . . . . . . . . . . . . . . . . . . . . 16
   5.  Protocol Parameters and Constants  . . . . . . . . . . . . . . 14 16
     5.1.  Protocol and Port Numbers  . . . . . . . . . . . . . . . . 14 17
     5.2.  Multicast Address  . . . . . . . . . . . . . . . . . . . . 15 17
     5.3.  Local History Times  . . . . . . . . . . . . . . . . . . . 15 17
     5.4.  Message Intervals  . . . . . . . . . . . . . . . . . . . . 15 18
     5.5.  Advertised Information Validity Times  . . . . . . . . . . 16 18
     5.6.  Received Message Validity Times  . . . . . . . . . . . . . 17 19
     5.7.  Jitter . . . . . . . . . . . . . . . . . . . . . . . . . . 17 20
     5.8.  Hop Limit Parameter  . . . . . . . . . . . . . . . . . . . 18 20
     5.9.  Willingness  . . . . . . . . . . . . . . . . . . . . . . . 18 21
     5.10. Parameter Change Constraints . . . . . . . . . . . . . . . 19 21
   6.  Information Bases  . . . . . . . . . . . . . . . . . . . . . . 20 22
     6.1.  Local Information Base . . . . . . . . . . . . . . . . . . 21 23
       6.1.1.  Originator Set . . . . . . . . . . . . . . . . . . . . 21 23
       6.1.2.  Local Attached Network Set . . . . . . . . . . . . . . 21 24
     6.2.  Neighbor Information Base  . . . . . . . . . . . . . . . . 22 24
     6.3.  Topology Information Base  . . . . . . . . . . . . . . . . 22 25
       6.3.1.  Advertised Neighbor  Advertising Remote Router Set  . . . . . . . . . . . . . . . 22 26
       6.3.2.  Advertising Remote  Router Topology Set  . . . . . . . . . . . . 23
       6.3.3.  Topology Set . . . . . . . . . 26
       6.3.3.  Routable Address Topology Set  . . . . . . . . . . . . 23 27
       6.3.4.  Attached Network Set . . . . . . . . . . . . . . . . . 24 27
       6.3.5.  Routing Set  . . . . . . . . . . . . . . . . . . . . . 25 28
     6.4.  Processing and Forwarding  Received Message Information Base  . . . . . . . . 25 . . . . 28
       6.4.1.  Received Set . . . . . . . . . . . . . . . . . . . . . 25 29
       6.4.2.  Processed Set  . . . . . . . . . . . . . . . . . . . . 26 29
       6.4.3.  Forwarded Set  . . . . . . . . . . . . . . . . . . . . 26
       6.4.4.  Relay Set  . . . . . . . . 30
     6.5.  Corresponding Protocol Tuples  . . . . . . . . . . . . . . 27 30
   7.  Message Processing and Forwarding  . . . . . . . . . . . . . . 27 31
     7.1.  Actions when Receiving a Message . . . . . . . . . . . . . 28 32
     7.2.  Message Considered for Processing  . . . . . . . . . . . . 28 32
     7.3.  Message Considered for Forwarding  . . . . . . . . . . . . 29 33
   8.  Packets and Messages . . . . . . . . . . . . . . . . . . . . . 31 35
     8.1.  HELLO Messages . . . . . . . . . . . . . . . . . . . . . . 32 36
       8.1.1.  HELLO Message TLVs . . . . . . . . . . . . . . . . . . 32 37
       8.1.2.  HELLO Message Address Block TLVs . . . . . . . . . . . 33 37
     8.2.  TC Messages  . . . . . . . . . . . . . . . . . . . . . . . 33 37
       8.2.1.  TC Message TLVs  . . . . . . . . . . . . . . . . . . . 34 39
       8.2.2.  TC Message Address Block TLVs  . . . . . . . . . . . . 34 39
   9.  HELLO Message Generation . . . . . . . . . . . . . . . . . . . 35 40
     9.1.  HELLO Message: Transmission  . . . . . . . . . . . . . . . 35 41
   10. HELLO Message Processing . . . . . . . . . . . . . . . . . . . 36 41
     10.1. Updating Willingness . . . . . . . . . . . . . . . . . . . 36 42
     10.2. Updating MPR Selectors . . . . . . . . . . . . . . . . . . 36
     10.3. Symmetric 1-Hop and 2-Hop Neighborhood Changes . . . . . . 37 42
   11. TC Message Generation  . . . . . . . . . . . . . . . . . . . . 38 43
     11.1. TC Message: Message Transmission  . . . . . . . . . . . . . . . . . 39 44
   12. TC Message Processing  . . . . . . . . . . . . . . . . . . . . 40 45
     12.1. Invalid Message  . . . . . . . . . . . . . . . . . . . . . 40 45
     12.2. Initial TC Message Processing Definitions  . . . . . . . . . . . . . . 41 47
     12.3. Initial TC Message Processing  . . . . . . . . . . . . . . 42 47
       12.3.1. Populating the Advertising Remote Router Set . . . . . 42 48
       12.3.2. Populating the Router Topology Set . . . . . . . . . . . . . 43 48
       12.3.3. Populating the Attached Network Routable Address Topology Set . . . . . 49
       12.3.4. Populating the Attached Network Set  . . . . . . . . . 43 49
     12.4. Completing TC Message Processing . . . . . . . . . . . . . 44 50
       12.4.1. Purging the Router Topology Set  . . . . . . . . . . . 50
       12.4.2. Purging the Routable Address Topology Set  . . . . . . 44
       12.4.2. 50
       12.4.3. Purging the Attached Network Set . . . . . . . . . . . 44 51
   13. Information Base Changes . . . . . . . . . . . . . . . . . . . 45
   14. Selecting MPRs . 51
     13.1. Originator Address Changes . . . . . . . . . . . . . . . . 51
     13.2. Neighbor State Changes . . . . . . . 46
   15. Populating Derived Sets . . . . . . . . . . . 51
     13.3. Advertised Neighbor Changes  . . . . . . . . 48
     15.1. Populating the Relay Set . . . . . . . 52
     13.4. Advertising Remote Router Tuple Expires  . . . . . . . . . 52
     13.5. Neighborhood Changes and MPR Updates . 48
     15.2. Populating the Advertised Neighbor Set . . . . . . . . . . 48
   16. 53
     13.6. Routing Set Calculation Updates  . . . . . . . . . . . . . . . . . . . 49
     16.1. Network Topology Graph 54
   14. Selecting MPRs . . . . . . . . . . . . . . . . . . 49
     16.2. Populating the . . . . . . 54
   15. Routing Set Calculation  . . . . . . . . . . . . . . . . 50
     16.3. Routing Set Updates . . . 56
     15.1. Network Topology Graph . . . . . . . . . . . . . . . . . . 56
     15.2. Populating the Routing Set . . . . . . 51
   17. . . . . . . . . . . 58
   16. Proposed Values for Parameters and Constants . . . . . . . . . 51
     17.1. 59
     16.1. Local History Time Parameters  . . . . . . . . . . . . . . 51
     17.2. 59
     16.2. Message Interval Parameters  . . . . . . . . . . . . . . . 51
     17.3. 59
     16.3. Advertised Information Validity Time Parameters  . . . . . 52
     17.4. 59
     16.4. Received Message Validity Time Parameters  . . . . . . . . 52
     17.5. 60
     16.5. Jitter Time Parameters . . . . . . . . . . . . . . . . . . 52
     17.6. 60
     16.6. Hop Limit Parameter  . . . . . . . . . . . . . . . . . . . 52
     17.7. 60
     16.7. Willingness Parameter and Constants  . . . . . . . . . . . 52
   18. 60
   17. Sequence Numbers . . . . . . . . . . . . . . . . . . . . . . . 52
   19. IANA Considerations 60
   18. Extensions . . . . . . . . . . . . . . . . . . . . . 53
     19.1. Message Types . . . . . 61
   19. Security Considerations  . . . . . . . . . . . . . . . . . 53
     19.2. Message TLV Types . . 62
     19.1. Confidentiality  . . . . . . . . . . . . . . . . . . 53
     19.3. Address Block TLV Types . . . 62
     19.2. Integrity  . . . . . . . . . . . . . . 54
   20. Security Considerations . . . . . . . . . . 62
     19.3. Interaction with External Routing Domains  . . . . . . . . 63
   20. IANA Considerations  . 55
     20.1. Confidentiality . . . . . . . . . . . . . . . . . . . . 64
     20.1. Expert Review: Evaluation Guidelines . 55
     20.2. Integrity . . . . . . . . . . 64
     20.2. Message Types  . . . . . . . . . . . . . . 56
     20.3. Interaction with External Routing Domains . . . . . . . . 57
   21. Contributors 64
     20.3. Message-Type-specific TLV Type Registries  . . . . . . . . 64
     20.4. Message TLV Types  . . . . . . . . . . . . . . . . . 58
   22. Acknowledgments . . . 65
     20.5. Address Block TLV Types  . . . . . . . . . . . . . . . . . 66
   21. Contributors . . . 58
   23. References . . . . . . . . . . . . . . . . . . . . . . 67
   22. Acknowledgments  . . . . 58
     23.1. Normative . . . . . . . . . . . . . . . . . . . 68
   23. References . . . . . . . . . . . . . . . . . . . 58
     23.2. Informative . . . . . . . 68
     23.1. Normative References . . . . . . . . . . . . . . . . . . 59
   Appendix A.  Router Configuration . 68
     23.2. Informative References . . . . . . . . . . . . . . . . 60 . . 69
   Appendix B. A.  Example Algorithm for Calculating MPRs  . . . . . . . 60
     B.1. 69
     A.1.  Terminology  . . . . . . . . . . . . . . . . . . . . . . . 61
     B.2. 70
     A.2.  MPR Selection Algorithm for each OLSRv2 Interface  . . . . 61 71
   Appendix C. B.  Example Algorithm for Calculating the Routing Set . . 62
     C.1.  Add 71
     B.1.  Local Symmetric Links Interfaces and Neighbors . . . . . . . . . . . . . . 72
     B.2.  Add Neighbor Routers . . . . . . 62
     C.2. . . . . . . . . . . . . . 72
     B.3.  Add Remote Symmetric Links Routers . . . . . . . . . . . . . . . . 63
     C.3. . . . . 73
     B.4.  Add Neighbor Addresses . . . . . . . . . . . . . . . . . . 73
     B.5.  Add Remote Routable Addresses  . . . . . . . . . . . . . . 74
     B.6.  Add Attached Networks  . . . . . . . . . . . . . . . . . . 64 74
     B.7.  Add 2-Hop Neighbors  . . . . . . . . . . . . . . . . . . . 75
   Appendix D. C.  Example Message Layout  . . . . . . . . . . . . . . . 65 76
   Appendix E. D.  Constraints . . . . . . . . . . . . . . . . . . . . . 67 77
   Appendix F. E.  Flow and Congestion Control . . . . . . . . . . . . . 70 81

1.  Introduction

   The Optimized Link State Routing protocol version 2 (OLSRv2) is an
   update to OLSRv1 as published in [RFC3626].  Compared to [RFC3626],
   OLSRv2 retains the same basic mechanisms and algorithms, while using
   a more flexible and efficient signaling framework, and includes some
   simplification of the messages being exchanged.

   OLSRv2 is developed for mobile ad hoc networks.  It operates as a
   table driven, proactive protocol, i.e. it exchanges topology
   information with other routers in the network regularly.  It  OLSRv2 is
   an optimization of the classical link state routing protocol.  The  Its
   key concept used in the protocol is that of MultiPoint Relays (MPRs).  Each router selects
   a set of its neighbor routers (which "cover" all of its symmetrically
   connected 2-hop neighbor routers) as MPRs.
   Control traffic  MPRs are then used to
   achieve both flooding reduction and topology reduction.

   Flooding reduction is achieved by control traffic being flooded
   through the network using hop by hop forwarding, but where with a router
   only needs needing to forward control traffic
   directly which is first received
   directly from its MPR selectors (routers one of the routers which have selected it as an MPR). MPR
   (its "MPR selectors").  This mechanism, denoted "MPR flooding",
   provides an efficient mechanism for information distribution within
   the MANET by reducing the number of transmissions required.

   Routers

   Topology redction is achieved by a mechanism where the routers
   selected as MPRs also have a special responsibility when declaring link
   state information in the network.  A sufficient requirement for
   OLSRv2 to provide shortest (lowest hop count) path 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, as well as being used to facilitate MPR flooding,  Thus the use of
   MPRs allows the 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
   "symmetric", i.e. bidirectional, links.  Therefore, selecting routes
   through MPRs automatically avoids the problems associated with data packet transfer
   over unidirectional links (such as the problem of not getting link
   layer acknowledgments at each hop, for link layers employing this
   technique).

   OLSRv2 uses and extends [NHDP] and uses [RFC5444], [RFC5497] and,
   optionally, [RFC5148].  (These  These other protocols and specifications were
   all originally created as part of OLSRv2, but have been specified
   separately for wider use.) use.

   OLSRv2 makes no assumptions about the underlying link layer.
   However,  OLSRv2,
   through its use of [NHDP], may use link layer information and
   notifications when available and applicable.

   OLSRv2, as OLSRv1, inherits its concept of forwarding and relaying
   from HIPERLAN (a MAC layer protocol) which is standardized by ETSI
   [HIPERLAN], [HIPERLAN2].

2.  Terminology

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in
   [RFC2119].

   All terms introduced in [RFC5444], including "packet", "message",
   "Address Block", "TLV Block", and "TLV", are to be interpreted as
   described there.

   All terms introduced in [NHDP], including "interface", "MANET
   interface", "address", "symmetric link", "symmetric 1-hop neighbor",
   "symmetric 2-hop neighbor", "constant", "interface parameter", and
   "router parameter", are to be interpreted as described there.

   Additionally, this document uses the following terminology:

   Router -  A MANET router which implements the Optimized Link State
      Routing protocol version 2 as specified in
      this document.

   OLSRv2 interface -  A MANET interface, interface running OLSRv2.  Note that all
      references this protocol.

   Routable address -   An address which may be used as the destination
      of a packet.  A router MUST be able to MANET interfaces 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 [NHDP] refer to OLSRv2
      interfaces when using [NHDP] scope to support OLSRv2. less than
      the entire MANET, MUST NOT be considered as routable addresses.

   Originator address -  An address which is unique (within the MANET)
      to the selecting a router.  A router MUST select an originator address; it MAY
      choose one of its interface addresses as its originator address.
      If it selects a routable address then this MUST be one which this
      router will accept as destination.  An originator address MUST NOT
      have a prefix length.  An

   Message originator address MUST -  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 all messages
      generated by this protocol, and the message as specified 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
      (both inclusive), which represents the router's willingness to be
      selected as an MPR.

   Willing symmetric 1-hop neighbor -  A symmetric 1-hop neighbor of
      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
      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
      symmetric 1-hop neighbor of router Y.

   Symmetric strict 2-hop neighbor through OLSRv2 interface I -  A
      symmetric strict 2-hop neighbor of the router with OLSRv2
      interface I which is a symmetric
      1-hop neighbor of a willing symmetric 1-hop neighbor of that router via a symmetric link using through
      OLSRv2 interface I. The router MAY elect to consider only
      information received over OLSRv2 interface I in making this
      determination.

   Symmetric strict 2-hop neighborhood -  The symmetric strict 2-hop
      neighborhood of a router X is the set of symmetric strict 2-hop
      neighbors of router X.

   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
      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
      greater than one.

   MPR selector -  A router, Y, is an MPR selector of router X if router
      Y has selected router X as MPR.

   MPR flooding -  The optimized MANET-wide information distribution
      mechanism, employed by this protocol, in which a message is
      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]
   and [NHDP].

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
      (MANETs) [RFC2501].

   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
      networks.

   o  Supports routers that each have one or more participating OLSRv2
      interfaces.  The set of a router's interfaces may change over
      time.  Each OLSRv2 interface may have one or more addresses (which
      may have prefix lengths), and these may also be dynamically
      changing.

   o  Enables hop-by-hop routing, i.e., each router can use its local
      information provided by OLSRv2 this protocol to route packets.

   o  Continuously maintains routes to all destinations in the network,
      i.e., routes are instantly available and data traffic is subject
      to no delays due to route discovery.  Consequently, no data
      traffic buffering is required.

   o  Supports routers which have non-OLSRv2 interfaces which may be
      local to a router or which can serve as gateways towards other
      networks.

   o  Is optimized for large and dense networks: the larger and more
      dense a network, the more optimization can be achieved by using
      MPRs, compared to the classic link state algorithm.

   o  Uses the message format specified in [RFC5444].  This includes the
      definition of a TC Message Type, used for MANET wide signaling of
      network topology information.

   o  Allows "external" and "internal" extensibility as enabled by
      [RFC5444].

   o  Uses [NHDP] for discovering each OLSRv2 router's 1-hop and symmetric
      2-hop neighbors, and extends [NHDP] by addition of MPR and
      willingness information.

   o  Is designed to work in a completely distributed manner, and does
      not depend on any central entity.

4.  Protocol Overview and Functioning

   The objective of OLSRv2 is, this protocol is for each router to, independently:

   o  Identify all destinations in the network.

   o  Identify a sufficient subset of links in the network, in order
      that shortest paths can be calculated to all available
      destinations.

   o  Provide a Routing Set, containing these shortest paths from this
      router to all destinations. destinations (routable addresses and local links).

4.1.  Overview

   These objectives are achieved achieved, for each router router, by:

   o  Using [NHDP] to identify symmetric 1-hop neighbors and symmetric
      2-hop neighbors.

   o  Independently selecting MPRs from among its symmetric 1-hop
      neighbors such that all symmetric 2-hop neighbors are reachable
      via at least one symmetric 1-hop neighbor.  An analysis and
      examples of MPR selection algorithms is given in [MPR], a
      suggested algorithm is included in this specification.  Note that
      it is not necessary for routers to use the same algorithm in order
      to
      interoperate. interoperate in the same MANET.

   o  Signaling its MPR selection by extending [NHDP] to include this
      information in outgoing HELLO messages. messages, by the addition of MPR
      Address Block TLV(s) associated with appropriate addresses.

   o  Extracting its MPR selectors from received HELLO messages. messages, using
      the included MPR Address Block TLV(s).

   o  Reporting its willingness to be an MPR in HELLO messages. messages, by the
      addition on an MPR_WILLING Message TLV.  The router's willingness
      to be an MPR indicates how willing it is to participate in MPR
      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
      throughout the MANET, by using TC (Topology Control) messages,
      defined in this specification.

   o  Diffusing TC messages by using flooding reduction mechanism,
      denoted "MPR flooding": only the MPRs of a router will retransmit
      messages received from (i.e., originated or last relayed by) that
      router.

   Note that the indicated extensions to [NHDP] are of forms permitted
   by that specification.

   This specification defines, in turn:

   o  Parameters and constants used by OLSRv2, this protocol, in addition to
      those specified in [NHDP].  Parameters used by OLSRv2 may be, this protocol may,
      where appropriate, be specific to a given OLSRv2 interface, or to an OLSRv2
      a router.  OLSRv2  This protocol allows all parameters to be changed
      dynamically, and to be set independently for each OLSRv2 router or each
      OLSRv2 interface, as appropriate.

   o  Extensions to the Information Bases specified in [NHDP], and [NHDP].

   o  Two new Information Bases: the Topology Information Base and Processing and Forwarding the
      Received Message Information Base.

   o  An Address Block TLV,  A requirement for each router to have an originator address to be
      included within in the HELLO messages of
      [NHDP], allowing a router to signal MPR selection. [NHDP].

   o  A Message TLV, to be included within in the HELLO messages of [NHDP],
      allowing a router to indicate its willingness to be an MPR.

   o  The  An Address Block TLV, to be included in the HELLO messages of
      [NHDP], allowing a router to signal its MPR flooding mechanism. selection.

   o  The format of MPR flooding mechanism, including the TC inclusion of message that is
      originator address and sequence number to manage duplicate
      messages.

   o  TC messages, which are used for MANET wide
      signaling. 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
      the Information Bases.

   o  The updating of the Topology Information Bases Base according to
      received TC messages.

   o  The response to other events, such as the expiration of
      information in the Information Bases.

   OLSRv2

   This protocol inherits the stability of a link state algorithm and
   has the advantage of having routes immediately available when needed needed,
   due to its proactive nature.

   OLSRv2

   This protocol only interacts with IP through routing table
   management, and the use of the sending IP address for IP datagrams
   containing OLSRv2
   messages.

4.1. packets.

4.2.  Routers and Interfaces

   In order for a router to participate in a MANET, it MUST have at
   least one, and possibly more, OLSRv2 interfaces.  Each OLSRv2
   interface:

   o  Is configured with one or more addresses, as specified in [NHDP].
      These addresses MUST each be unique within the MANET. 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
      [NHDP].

   o  Has an Interface Information Base, extending that specified in
      [NHDP].

   o  Generates and processes HELLO messages according to [NHDP],
      extended as specified in Section 9 and Section 10.

   In addition to a set of MANET OLSRv2 interfaces as described above, each
   router:

   o  Has a number  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 parameters, adding for which it is to those specified in
      [NHDP].

   o  Has 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
      [NHDP].

   o  Has a Local Information Base, extending that specified in [NHDP]. [NHDP],
      including selection of an originator address and recording any
      locally attached networks.

   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
      for generation and processing of received in
      TC messages. messages and derived therefrom.

   o  Has a Processing and Forwarding Received Message Information Base, recording information required for MPR flooding, and
      about received messages to ensure that each TC message is only
      processed once, and forwarded at most once on each OLSRv2
      interface, by a router.

   o  Generates and processes TC messages.

4.2.

4.3.  Information Base Overview

   Each router maintains the Information Bases described in the
   following sections.  These are used for describing the protocol in
   this document.  An implementation of this protocol MAY maintain this
   information in the indicated form, or in any other organization which
   offers access to this information.  In particular, note that it is
   not necessary to remove Tuples from Sets at the exact time indicated,
   only to behave as if the Tuples were removed at that time.

4.2.1.

4.3.1.  Local Information Base

   The Local Information Base is specified in [NHDP] and contains a
   router's local configuration.  It is extended in this specification
   to also contain record an originator address and to include a router's:

   o  Originator Set, containing addresses that were recently used as
      this router's originator address.

   o  Local Attached Network Set, containing addresses of networks to
      which this router can act as a gateway.

   The Originator Set address, and is used to enable a router
      to recognize and discard control traffic which was originated by
      the router itself.

   The

   o  Local Attached Network Set is used to enable a router to include
   advertisement Set, containing addresses of reachability networks to a network, for
      which the this router can act as a gateway, when generating and advertises in its TC
      messages.

4.2.2.

4.3.2.  Interface Information Bases

   The Interface Information Bases, one for each OLSRv2 interface, are
   specified in [NHDP].  In addition to the uses in [NHDP], information
   recorded in the Interface Information Bases is used for completing
   the Routing Set.

4.2.3.

4.3.3.  Neighbor Information Base

   The Neighbor Information Base is specified in [NHDP], and is extended
   to also record each neighbor's originator address, the willingness of
   each neighbor to be an MPR, as well as this router's MPR
   relationships with each neighbor.  Specifically,
   each Neighbor Tuple is extended to record whether that neighbor is (whether an MPR and/or an MPR
   selector of this router, as well as the neighbor's
   willingness that neighbor) and whether that neighbor is to be an MPR.

   In addition to the uses
   advertised in [NHDP], information TC messages.

   A router selects some of its symmetric 1-hop neighbors as MPRs (see
   Section 14).  That selection is recorded in the Neighbor Information Base Set. This
   selection is used to determine inclusion of then reported in the router's HELLO messages, extending
   the specification in [NHDP], by using an MPR Address Block TLV, defined in this document, as well as for
   populating the Advertised Neighbor Set and the Relay Sets of TLV.  In
   making that selection a
   router.

4.2.4.  Topology Information Base

   The Topology Information Base contains:

   o  An Advertised 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, describing Set.

   A router also records in the Neighbor Set which symmetric 1-hop
   neighbors of this router that are to be advertised in TC messages. have selected it as an MPR (i.e. its MPR selectors).  This set contains at least
   is determined from the MPR selectors of this router, and
      is associated with an Advertised Neighbor Sequence Number (ANSN), TLVs in received HELLO messages.  It also
   records which symmetric 1-hop neighbors that it is incremented for each change made to advertise
   connectivity to in its TC messages; this Advertised MUST include all of its MPR
   selectors.

   The Neighbor Set.

   o  An Advertising Remote Router Set, describing Set finally records each other router
      from which TC 1-hop neighbor's originator
   address, as included in its HELLO messages have been received.

   o  A Topology in an extension to [NHDP].
   This, and other information in the Neighbor Set, recording links between routers including each 1-hop
   neighbor's routable addresses, is used in advertising the MANET, as
      described by received selected
   symmetric 1-hop neighbors in TC messages.

   o  An Attached Network Set, recording networks

4.3.4.  Topology Information Base

   The purpose of the Topology Information Base is to record information
   used, in addition to which a remote
      router has advertised that it may act as a gateway.

   o  A Routing Set, calculated based on in the Local Information Base, the
   Interface Information
      Bases, Bases and the Neighbor Information Base, and to
   construct the Routing Set (which is also included in 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 Base).

   This specification describes the calculation of the Routing Set to update based
   on a Topology Graph constructed in two phases.  First, a "backbone"
   graph representing the routing table, this selection routers in the MANET, and the connectivity
   between them, is
      outside constructed from the Local Information Base, the scope of OLSRv2.)

   The Advertised
   Neighbor Information Base and the Router Topology Set is used for when generating TC messages; in the Advertised Neighbor Sequence Number Topology
   Information Base.  Second, this graph is included in each TC
   message, thereby allowing a receiving router to identify if a TC
   message contains fresh or outdated information.

   The Advertising Remote Router Set, "decorated" with additional
   destination addresses using the Local Information Base, and the
   Routable Address Topology Set and the Attached Network Set are all updated upon receipt of TC messages, and are used
   when determining in the contents of
   Topology Information Base.

   The Topology Graph does not need to be recorded in the Topology
   Information Base, it can either be constructed as required when the
   Routing Set.

4.2.5.  Processing Set is to be changed, or need not be explicitly constructed
   (as illustrated in Appendix B.  An implementation MAY construct and Forwarding Information Base
   retain the Topology Graph if preferred.

   The Processing and Forwarding Topology Information Base in each router contains:

   o  A Received  An Advertising Remote Router Set, describing recording each other router from
      which TC messages have been received.  This is used in order to
      determine if a received by this router.

   o  A Processed Set, describing TC messages processed by this router.

   o  A Forwarded Set, describing contains fresh or outdated
      information; the TC messages forwarded by this router. message is ignored in the latter case.

   o  A Relay Set for each OLSRv2 interface, describing the set of
      neighbor Router Topology Set, recording links between routers in the
      MANET, as described by received TC messages.

   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 traffic TC messages.

   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 Routing Set, recording routes from this router to all available
      destinations.  The IP routing table is to be relayed (if
      otherwise appropriate). 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 Processing and Forwarding 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 Forwarded Set, describing TC messages forwarded by this router.

   The Received Message Information Base serves the MPR flooding
   mechanism by enabling ensuring that received messages are forwarded at most once,
   once by a router. router, and also ensures that received messages are
   processed exactly once.

4.3. once by a router.

4.4.  Signaling Overview

   OLSRv2 uses the neighborhood discovery

   This protocol [NHDP], and generates and processes HELLO messages according to
   [NHDP], extended according to Section 9 and Section 10.

   OLSRv2 10 of this
   specification to include an originator address and MPR selection
   information.

   This protocol specifies a single message type, the TC message.

   OLSRv2 does not require reliable transmission

   This protocol is tolerant of unreliable transmissions of TC messages;
   each router sends TC messages periodically, and can therefore sustain
   a reasonable loss of some such messages.  Such losses may occur more
   frequently in wireless networks due to collisions or other
   transmission problems.  OLSRv2  This protocol MAY use "jitter", randomized
   adjustments to message transmission times, to reduce the incidence of
   collisions as specified in [RFC5148].

   OLSRv2 does not require sequenced delivery of TC messages.  Each

   This protocol is tolerant of out of sequence delivery of TC messages
   due to in transit message contains a sequence number reordering (possibly due to message
   alternative routing by flooding and message loss).  Each router
   maintains an Advertised Neighbor Sequence Number (ANSN) which is
   incremented when its recorded neighbor information that is to be
   included in its TC messages changes.  This ANSN is included in the
   message contents change.  Thus the
   router's TC messages.  The recipient of a TC message can, if
   required, easily can used this
   included ANSN to identify which of the information it has received is more
   most recent, even if messages have been re-ordered while in transmission. 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
   contains at least the set of addresses
   advertises all of the originating router's MPR selectors. selectors, it may also
   advertise other symmetric 1-hop neighbors.  Complete TC messages are
   generated periodically (and also, optionally, in response to
   neighborhood changes).  Incomplete TC messages may be used to report
   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
   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
   selectors.

   Some TC messages may be MPR flooded over only part of the network,
   e.g., allowing a router to ensure that nearer routers are kept more
   up to date than distant routers, such as is used in Fisheye State
   Routing [FSR] and Fuzzy Sighted Link State routing [FSLS].  This is
   enabled
   in OLSRv2 by using [RFC5497].

5.  Protocol Parameters and Constants

4.5.  Routing Set

   The parameters purpose of the Routing Set is to determine and constants used in this specification are those
   defined in [NHDP] plus those defined in this section.  The separation
   in [NHDP] into record routes
   (local interface parameters, router parameters address and constants
   is also used in OLSRv2, however next hop interface address) to all but one (RX_HOLD_TIME)
   possible routable addresses and of the
   parameters added by OLSRv2 all destinations that are router parameters.  Parameters may be
   classified into local,
   i.e. within one hop, to the following categories:

   o  Local history times

   o  Message intervals 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

   The parameters and constants used in this specification are those
   defined in [NHDP] plus those defined in this section.  The separation
   in [NHDP] into interface parameters, router parameters and constants
   is also used in this specification, however all but one
   (RX_HOLD_TIME) of the parameters added by this protocol are router
   parameters.  Parameters may be categorized as follows:

   o  Local history times

   o  Message intervals

   o  Advertised information validity times

   o  Received message validity times
   o  Jitter times

   o  Hop limits

   o  Willingness

   In addition, constants for particular cases of a router's willingness
   to be an MPR are defined.  These parameters and constants are
   detailed in the following sections.  As for the parameters in [NHDP],
   parameters defined in this document may be changed dynamically by a
   router, and need not be the same on different routers, even in the
   same MANET, or or, for interface parameters, on different interfaces of
   the same router (for
   interface parameters). router.

5.1.  Protocol and Port Numbers

   This protocol specifies TC messages, which are included in packets as
   defined by [RFC5444].  These packets may be sent either using the
   "manet" protocol number or the "manet" well-known UDP port number, as
   specified in [RFC5498].

   TC messages and HELLO messages [NHDP] SHOULD, in a given deployment
   of OLSRv2, this protocol, both be using the same of either of IP or UDP, in
   order that it is possible to combine messages of both protocols into
   the same [RFC5444] packet. packet for transmission.

5.2.  Multicast Address

   This protocol specifies HELLO TC messages, which are included in packets as
   defined by [RFC5444].  These packets may be locally transmitted using
   the link local multicast address "LL-MANET-Routers", as specified in
   [RFC5498].

5.3.  Local History Times

   The following router parameter manages the time for which local
   information is retained:

   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
      own messages.

   The following constraint applies to this parameter:

   o  O_HOLD_TIME >= 0

5.4.  Message Intervals

   The following router parameters regulate TC message transmissions by
   a router.  TC messages are usually sent periodically, but MAY also be
   sent in response to changes in the router's Advertised Neighbor Set
   and and/or Local
   Attached Network Set. With a larger value of the parameter
   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
   highly dynamic network.  However because a router has no knowledge
   of, for example, routers remote to it (i.e. beyond 2 hops away)
   joining the network, TC messages MUST NOT be sent purely
   responsively.

   TC_INTERVAL  - is the maximum time between the transmission of two
      successive TC messages by this router.  When no TC messages are
      sent in response to local network changes (by design, or because
      the local network is not changing) then TC messages SHOULD be sent
      at a regular interval TC_INTERVAL, possibly modified by jitter as
      specified in [RFC5148].

   TC_MIN_INTERVAL  - is the minimum interval between transmission of
      two successive TC messages by this router.  (This minimum interval
      MAY be modified by jitter, as specified in [RFC5148].)

   The following constraints apply to these parameters:

   o  TC_INTERVAL > 0

   o  TC_MIN_INTERVAL >= 0

   o  TC_INTERVAL >= TC_MIN_INTERVAL

   o  If INTERVAL_TIME TLVs as defined in [RFC5497] are included in TC
      messages, then TC_INTERVAL MUST be representable as described in
      [RFC5497].

5.5.  Advertised Information Validity Times

   The following router parameters manage the validity time of
   information advertised in TC messages:

   T_HOLD_TIME  - is used to define the minimum Value in the
      VALIDITY_TIME TLV included in all TC messages sent by this router.
      If a single value of parameter TC_HOP_LIMIT (see Section 5.8) is
      used then this will be the only Value in that TLV.

   A_HOLD_TIME  - is the period during which TC messages are sent after
      they no longer have any advertised information to report, but are
      sent in order to accelerate outdated information removal by other
      routers.

   The following constraints apply to these parameters:

   o  T_HOLD_TIME > 0

   o  A_HOLD_TIME >= 0

   o  T_HOLD_TIME >= TC_INTERVAL

   o  If TC messages can be lost, then both T_HOLD_TIME and A_HOLD_TIME
      SHOULD be significantly greater than TC_INTERVAL; a value >= 3 x
      TC_INTERVAL is RECOMMENDED.

   o  T_HOLD_TIME MUST be representable as described in [RFC5497].

5.6.  Received Message Validity Times

   The following parameters manage the validity time of recorded
   received message information:

   RX_HOLD_TIME  - is an interface parameter, and is the period after
      receipt of a message by the appropriate OLSRv2 interface of this
      router for which that information is recorded, in order that the
      message is recognized as having been previously received on this
      OLSRv2 interface.

   P_HOLD_TIME  - is a router parameter, and is the period after receipt
      of a message which is processed by this router for which that
      information is recorded, in order that the message is not
      processed again if received again.

   F_HOLD_TIME  - is a router parameter, and is the period after receipt
      of a message which is forwarded by this router for which that
      information is recorded, in order that the message is not
      forwarded again if received again.

   The following constraints apply to these parameters:

   o  RX_HOLD_TIME > 0

   o  P_HOLD_TIME > 0

   o  F_HOLD_TIME > 0
   o  All of these parameters SHOULD be greater than the maximum
      difference in time that a message may take to traverse the MANET,
      taking into account any message forwarding jitter as well as
      propagation, queuing, and processing delays.

5.7.  Jitter

   If jitter, as defined in [RFC5148], is used then these the governing jitter
   parameters are as follows:

   TP_MAXJITTER  - represents the value of MAXJITTER used in [RFC5148]
      for periodically generated TC messages sent by this router.

   TT_MAXJITTER  - represents the value of MAXJITTER used in [RFC5148]
      for externally triggered TC messages sent by this router.

   F_MAXJITTER  - represents the default value of MAXJITTER used in
      [RFC5148] for messages forwarded by this router.  However before
      using F_MAXJITTER a router MAY attempt to deduce a more
      appropriate value of MAXJITTER, for example based on any
      INTERVAL_TIME or VALIDITY_TIME TLVs contained in the message to be
      forwarded.

   For constraints on these parameters see [RFC5148].

5.8.  Hop Limit Parameter

   The parameter TC_HOP_LIMIT is the hop limit set in each TC message.
   TC_HOP_LIMIT MAY be a single fixed value, or MAY be different in TC
   messages sent by the same router.  However each other router, at any
   hop count distance, SHOULD see a regular pattern of TC messages, in
   order that meaningful Values of INTERVAL_TIME and VALIDITY_TIME TLVs
   at each hop count distance can be included as defined in [RFC5497].
   Thus the pattern of TC_HOP_LIMIT SHOULD be defined to have this
   property.  For example the repeating pattern (255 4 4) satisfies this
   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
   pattern (255 255 4 4) does not satisfy this property because at hop
   counts greater than 4, message intervals are alternately TC_INTERVAL
   and 3 x TC_INTERVAL.

   The following constraints apply to this parameter:

   o  The maximum value of TC_HOP_LIMIT >= the network diameter in hops,
      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.

5.9.  Willingness

   Each router has a WILLINGNESS parameter, which MUST be in the range
   WILL_NEVER to WILL_ALWAYS, inclusive, and represents its the router's
   willingness to be an MPR, and hence its willingness to forward
   messages and be an intermediate router on routes.  If a router has
   WILLINGNESS = WILL_NEVER it does not perform these tasks.  A MANET
   using OLSRv2 this protocol with too many routers with having WILLINGNESS =
   WILL_NEVER will not function; it MUST be ensured, by administrative
   or other means, that this does not happen.

   Routers MAY have different WILLINGNESS values; however the three
   constants WILL_NEVER, WILL_DEFAULT and WILL_ALWAYS MUST have the
   values defined in Section 17. 16.  (Use of WILLINGNESS = WILL_DEFAULT
   allows a router to avoid including an MPR_WILLING TLV in its TC
   messages, use of WILLINGNESS = WILL_ALWAYS means that a router will
   always be selected as an MPR by all symmetric 1-hop neighbors.)

   The following constraints apply to this parameter:

   o  WILLINGNESS >= WILL_NEVER

   o  WILLINGNESS <= WILL_ALWAYS

5.10.  Parameter Change Constraints

   This section presents guidelines, applicable if protocol parameters
   are changed dynamically.

   O_HOLD_TIME

      *  If O_HOLD_TIME for a router changes, then O_time for all
         Originator Tuples MAY be changed.

   TC_INTERVAL

      *  If the TC_INTERVAL for a router increases, then the next TC
         message generated by this router MUST be generated according to
         the previous, shorter, TC_INTERVAL.  Additional subsequent TC
         messages MAY be generated according to the previous, shorter,
         TC_INTERVAL.

      *  If the TC_INTERVAL for a router decreases, then the following
         TC messages from this router MUST be generated according to the
         current, shorter, TC_INTERVAL.

   RX_HOLD_TIME

      *  If RX_HOLD_TIME for an OLSRv2 interface changes, then RX_time
         for all Received Tuples for that OLSRv2 interface MAY be
         changed.

   P_HOLD_TIME

      *  If P_HOLD_TIME changes, then P_time for all Processed Tuples
         MAY be changed.

   F_HOLD_TIME

      *  If F_HOLD_TIME changes, then F_time for all Forwarded Tuples
         MAY be changed.

   TP_MAXJITTER

      *  If TP_MAXJITTER changes, then the periodic TC message schedule
         on this router MAY be changed immediately.

   TT_MAXJITTER

      *  If TT_MAXJITTER changes, then externally triggered TC messages
         on this router MAY be rescheduled.

   F_MAXJITTER

      *  If F_MAXJITTER changes, then TC messages waiting to be
         forwarded with a delay based on this parameter MAY be
         rescheduled.

   TC_HOP_LIMIT

      *  If TC_HOP_LIMIT changes, and the router uses multiple values
         after the change, then message intervals and validity times
         included in TC messages MUST be respected.  The simplest way to
         do this is to start any new repeating pattern of TC_HOP_LIMIT
         values with its largest value.

6.  Information Bases

   The purpose of OLSRv2 this protocol is to determine the Routing Set, which
   may be used to update IP's Routing Table, providing "next hop"
   routing information for IP datagrams.  OLSRv2 maintains packets.  This specification includes the
   following Information Bases:

   Local Information Base  - as defined in [NHDP], extended by the
      inclusion of the router's originator address and the addition of
      an Originator Set, defined in Section 6.1.1 6.1.1, and a Local Attached
      Network Set, defined in Section 6.1.2.

   Interface Information Bases  - as defined in [NHDP], one an Interface
      Information Base for each OLSRv2 interface.

   Neighbor Information Base  - as defined in [NHDP], extended by the
      addition of three five elements to each Neighbor Tuple, and the
      inclusion of an Advertised Neighbor Sequence Number (ANSN), both
      as defined in Section 6.2.

   Topology Information Base  - this Information Base is specific to
      OLSRv2,
      this protocol, and is defined in Section 6.3.

   Processing and Forwarding

   Received Message Information Base  - this Information Base is
      specific to OLSRv2, this protocol, and is defined in Section 6.4.

   The ordering of sequence numbers, when considering which is the
   greater, is as defined in Section 18. 17.

6.1.  Local Information Base

   The Local Information Base as defined in [NHDP] is extended by by:

   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

   A router's Originator Set records addresses that were recently used
   as originator addresses by this router.  If a router's originator
   address is immutable then this set is always empty and MAY be
   omitted.  It consists of Originator Tuples:

      (O_orig_addr, O_time)

   where:

   O_orig_addr  is a recently used originator address; address, note that this
      does not include a prefix length;

   O_time  specifies the time at which this Tuple expires and MUST be
      removed.

6.1.2.  Local Attached Network Set

   A router's Local Attached Network Set records its local non-OLSRv2
   interfaces via which it can act as gateways to other networks.  The
   Local Attached Network Set is not modified by this protocol.  This
   protocol MAY respond to changes to the Local Attached Network Set,
   which MUST reflect corresponding changes in the router's status.  It
   consists of Local Attached Network Tuples:

      (AL_net_addr, AL_dist)

   where:

   AL_net_addr  is the network address of an attached network which can
      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_net_addr from this router.

   Attached networks local to this router only (i.e. not reachable
   except via this router) SHOULD be treated as local non-MANET
   interfaces, and added to the Local Interface Set, as specified in
   [NHDP], rather than being be added to the Local Attached Network Set.

   An

   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 this protocol to maintain routes from
   this router to networks recorded in the Local Attached Network Set.

   Local Attached Neighbor Tuples are removed from the Local Attached
   Network Set only when the routers' local attached network
   configuration changes, i.e., they are not subject to timer-based
   expiration or changes due to received messages.

6.2.  Neighbor Information Base

   Each Neighbor Tuple in the Neighbor Set, defined in [NHDP], has these
   additional elements:

   N_orig_addr  is the neighbor's originator address, which may be
      unknown.  Note that this originator address does not include a
      prefix length;

   N_willingness  is the router's 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
      an MPR by this router;

   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
      router.

6.3.  Topology Information Base

   The Topology Information Base stores information required for the
   generation and processing of TC messages, and information received

   N_advertised  is a boolean flag, describing if this router has
      elected to advertise a link to this neighbor in its TC messages.

   A Neighbor Tuple created (but not updated) by [NHDP] MUST set:

      N_orig_addr := unknown;

      N_willingness := WILL_NEVER;

      N_mpr := false;

      N_mpr_selector := false;

      N_advertised := false.

   The Neighbor Information Base also includes a variable, the
   Advertised Neighbor Set contains addresses of
   symmetric 1-hop neighbors which are to be reported Sequence Number (ANSN), whose value is included
   in TC messages. messages to indicate the freshness of the information
   transmitted.  The ANSN is incremented whenever advertised information
   (the originator and routable addresses included in Neighbor Tuples
   with N_advertised = true, and local attached networks recorded in the
   Local Attached Network Set in the Local Information Base) changes.

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 record information received in TC messages. Set.

   Additionally, a Routing Set is maintained, derived from the
   information recorded in the Neighborhood Local Information Base, Topology
   Set, Attached Network Set the Interface
   Information Bases, the Neighbor Information Base and the rest of the
   Topology Information Base.

6.3.1.  Advertising Remote Router Set.

6.3.1.  Advertised Neighbor Set

   A router's Advertised Neighbor Advertising Remote Router Set contains addresses of symmetric
   1-hop neighbors which are records information
   describing each remote router in the network that transmits TC
   messages, allowing outdated TC messages to be advertised through TC messages. recognized and
   discarded.  It consists of Advertised Neighbor Advertising Remote Router Tuples:

      (A_neighbor_addr)

   In addition, an Advertised Neighbor Set Sequence Number (ANSN)

      (AR_orig_addr, AR_seq_number, AR_time)

   where:

   AR_orig_addr  is
   maintained.  Each time the Advertised Neighbor Set originator address of a received TC message,
      note that this does not include a prefix length;

   AR_seq_number  is updated, the greatest 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 any TC messages.

   The Advertised Neighbor Set for a router is derived message received which
      originated from the Neighbor
   Set of that same router, specifically, each router with originator address in AR_orig_addr
      (i.e., which contributed to the
   N_neighbor_addr_list of a Neighbor Tuple MUST be an A_neighbor_addr
   if information contained in this
      Tuple);

   AR_time  is the corresponding N_mpr_selector = true, time at which this Tuple expires and MAY be an
   A_neighbor_addr if the corresponding N_mpr_selector = false.  No
   other address may be an A_neighbor_addr.  The Advertised Neighbor Set MUST therefore be updated when the Neighbor Set changes, see
   Section 13.  Advertised Neighbor Tuples are not subject to timer-
   based expiration. removed.

6.3.2.  Advertising Remote  Router Topology Set

   A router's Advertising Remote Router Topology Set records topology information
   describing each remote router about the links
   between routers in the network that transmits TC
   messages. MANET, allowing a "backbone" graph of all
   routers to be constructed using a minimum distance algorithm.  It
   consists of Advertising Remote Router Topology Tuples:

      (AR_orig_addr, AR_seq_number, AR_addr_list, AR_time)

      (TR_from_orig_addr, TR_to_orig_addr, TR_seq_number, TR_time)

   where:

   AR_orig_addr

   TR_from_orig_addr  is the originator address of a received TC message, router which can
      reach the router with originator address TR_to_orig_addr in one
      hop, note that this does not include a prefix length;

   AR_seq_number

   TR_to_orig_addr  is the originator address of a router which can be
      reached by the router with originator address TR_to_orig_addr in
      one hop, note that this does not include a prefix length;

   TR_seq_number  is the greatest ANSN in any TC message received which
      originated from the router with originator address AR_orig_addr
      TR_from_orig_addr (i.e., which contributed to the information
      contained in this Tuple);

   AR_addr_list  is an unordered list of the addresses of the router
      with originator address AR_orig_addr;

   AR_time  is

   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
   network. routable addresses within the MANET, and via which routers
   they may be reached.  It consists of Routable Address Topology
   Tuples:

      (T_dest_addr, T_orig_addr, T_seq_number, T_time)

      (TA_from_orig_addr, TA_dest_addr, TA_seq_number, TA_time)

   where:

   T_dest_addr  is an address of a destination router, which may be
      reached in one hop from the router with originator address
      T_orig_addr;

   T_orig_addr

   TA_from_orig_addr  is the originator address of a router which is the last
      hop on a path towards can
      reach the router with routable address T_dest_addr, TA_dest_addr in one hop,
      note that this does not include a prefix length;

   T_seq_number

   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 T_orig_addr
      TA_from_orig_addr (i.e., which contributed to the information
      contained in this Tuple);

   T_time

   TA_time  specifies the time at which this Tuple expires and MUST be
      removed.

6.3.4.  Attached Network Set

   A router's Attached Network Set records information about networks
   (which may be outside the MANET) attached to other routers. routers and their
   routable addresses.  It consists of Attached Network Tuples:

      (AN_net_addr, AN_orig_addr,

      (AN_orig_addr, AN_net_addr, AN_dist, AN_seq_number, AN_time)

   where:

   AN_net_addr

   AN_orig_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 originator address of a router which can act as
      gateway to the network with address AN_net_addr, note that this
      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_net_addr from the router with originator address AN_orig_addr;

   AN_seq_number  is the greatest ANSN in any TC message received which
      originated from the router with originator address AN_orig_addr
      (i.e., which contributed to the information contained in this
      Tuple);

   AN_time  specifies the time at which this Tuple expires and MUST be
      removed.

6.3.5.  Routing Set

   A router's Routing Set records the first hop along a selected path to
   each destination for which a route any such path is known.  It consists of
   Routing Tuples:

      (R_dest_addr, R_next_iface_addr, R_dist, R_local_iface_addr) R_local_iface_addr, R_dist)

   where:

   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
      attached network;

   R_next_iface_addr  is the address of the "next hop" on the selected
      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
      which a packet MUST be sent to reach the destination by the
      selected path.

   R_dist  is the number of hops on the selected path to the
      destination;

   The Routing Set for a router is derived from the contents of the other sets
   protocol Sets of the router, 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) removed, or the complete Routing Set
   recalculated) when routing paths are calculated. calculated, based on changes to
   these other protocol Sets.  Routing Tuples are not subject to timer-based timer-
   based expiration.

6.4.  Processing and Forwarding  Received Message Information Base

   The Processing and Forwarding Received Message Information Base records information 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 flooding.

6.4.1.  Received Set

   A router has a Received Set per local OLSRv2 interface.  Each Received Set
   records the signatures of messages which have been received over that
   OLSRv2 interface.  Each consists of Received Tuples:

      (RX_type, RX_orig_addr, RX_seq_number, RX_time)

   where:

   RX_type  is the received Message Type;

   RX_orig_addr  is the originator address of the received message; message, note
      that this does not include a prefix length;

   RX_seq_number  is the message sequence number of the received
      message;

   RX_time  specifies the time at which this Tuple expires and MUST be
      removed.

6.4.2.  Processed Set

   A router's router has a single Processed Set which records signatures of
   messages which have been processed by the router.  It consists of
   Processed Tuples:

      (P_type, P_orig_addr, P_seq_number, P_time)

   where:

   P_type  is the processed Message Type;

   P_orig_addr  is the originator address of the processed message; message, note
      that this does not include a prefix length;

   P_seq_number  is the message sequence number of the processed
      message;

   P_time  specifies the time at which this Tuple expires and MUST be
      removed.

6.4.3.  Forwarded Set

   A router's router has a single Forwarded Set which records signatures of
   messages which have been processed forwarded by the router.  It consists of
   Forwarded Tuples:

      (F_type, F_orig_addr, F_seq_number, F_time)

   where:

   F_type  is the forwarded Message Type;

   F_orig_addr  is the originator address of the forwarded message; message, note
      that this does not include a prefix length;

   F_seq_number  is the message sequence number of the forwarded
      message;

   F_time  specifies the time at which this Tuple expires and MUST be
      removed.

6.4.4.  Relay Set

   A router has

6.5.  Corresponding Protocol Tuples

   In a Relay Set per local OLSRv2 interface.  Each Relay Set
   records the addresses number of symmetric 1-hop neighbors, such that the
   router cases there is to forward messages received from those neighbors' OLSRv2
   interfaces, on that local OLSRv2 interface, if not otherwise excluded a natural correspondence from forwarding that message (e.g., by it having been previously
   forwarded).  It consists of Relay Tuples:

      (RY_neighbor_iface_addr)

   The Relay a
   Protocol Tuple in a Protocol Set for an interface to a single Protocol Tuple in
   another Protocol Set. The latter Protocol Tuple is derived from referred to as
   "corresponding" to the former.

   Specific examples include:

   o  There is a Local Interface Tuple corresponding to each Link Tuple,
      where the Link Tuple is in the Link Set for the
   same an OLSRv2 interface,
      and so Relay Tuples are removed when the Local Interface Tuple represents that OLSRv2 interface.

   o  There is a Neighbor Tuple corresponding to each Link Tuples in 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 of this interface are
   removed, or when processing otherwise suggests their removal.  Relay
   Tuples are not subject in the same Interface
      Information Base) corresponding to timer-based expiration. 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

   On receiving a packet, as defined in [RFC5444], a router divides the
   packet into the Packet Header and messages.  OLSRv2

   This protocol defines, and hence owns, the TC Message Type, and hence message type (see
   Section 20).  Thus, as specified in [RFC5444], this protocol receives
   all TC messages.
   OLSRv2 messages and is responsible for determining whether a and how
   each TC message is to be processed (updating Information Bases)
   and/or forwarded. forwarded, according to this specification.  OLSRv2 does not
   require any part of the Packet Header.

   This protocol also receives HELLO messages, which are defined, and
   hence owned, by [NHDP].  Received HELLO messages MUST be made available to
   OLSRv2  Such messages, when received on an OLSRv2 interface and after NHDP has
   interface, are made available to this protocol in two ways, both as
   permitted by [NHDP].  First, such received HELLO messages MUST be
   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.  OLSRv2 also processes
   thereof, unless discarded as malformed by [NHDP], for processing by
   this protocol.  HELLO
   messages, OLSRv2 does messages are not forward HELLO messages. forwarded by this protocol.

   Extensions to OLSRv2 this protocol which define, and hence own, other
   Messages Types, MAY manage the processing and/or forwarding of these
   messages using the same mechanism as for TC messages.  These
   mechanisms contain elements (P_type, RX_type, F_type) required only
   for such usage.

   The processing selection and forwarding mechanisms are designed to
   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
   the Message Body even if the message is forwarded (but not
   processed).  An implementation MAY either only parse the Message Body
   if necessary, or MAY always parse the Message Body.

   An 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.

7.1.  Actions when Receiving a Message

   If the router receives a HELLO message from [NHDP], then the message
   is
   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
   message or (or other Message Type defined by an extension to OLSRv2 this
   protocol and specified to use this process: process):

   1.  If the router recognizes from the originator address of the
       message that the message is one which the receiving router itself
       originated (i.e. is the current originator address of the this router, or is
       an O_orig_addr in an Originator Tuple) then the message MUST be
       silently discarded.

   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
           processing according to Section 7.2, AND;

       2.  If for the message is of a type which may be forwarded, including
           being a TC message, AND:

               -

           +  <msg-hop-limit> is present and <msg-hop-limit> > 1, AND;

               -

           +  <msg-hop-count> is not present or <msg-hop-count> < 255

           then the message is considered for forwarding according to
           Section 7.3.

7.2.  Message Considered for Processing

   If a message (the "current message") is considered for processing,
   then the following tasks MUST be performed:

   1.  If a Processed Tuple exists with:

       *  P_type = the Message Type of the current message, AND;

       *  P_orig_addr = the originator address of the current message,
          AND;

       *  P_seq_number = the message sequence number of the current
          message;

       then the current message MUST NOT be processed.

   2.  Otherwise:

       1.  Create a Processed Tuple with:

           +  P_type := the Message Type of the current message;

           +  P_orig_addr := the originator address of the current
              message;

           +  P_seq_number := the sequence number of the current
              message;

           +  P_time := current time + P_HOLD_TIME.

       2.  Process the current message according to its type.  For a TC
           message this is as defined in Section 12.

7.3.  Message Considered for Forwarding

   If a message (the "current message") is considered for forwarding,
   then the following tasks MUST be performed:

   1.  If the sending address (i.e., the source address of the IP
       datagram containing the current message) does not match (taking
       into account any address prefix) an address in an
       L_neighbor_iface_addr_list of a Link Tuple, with L_status =
       SYMMETRIC, in the Link Set for the OLSRv2 interface on which the
       current message was received (the "receiving interface") then the
       current message MUST be silently discarded.

   2.  Otherwise:

       1.  If a Received Tuple exists in the Received Set for the
           receiving interface, with:

           +  RX_type = the Message Type of the current message, AND;

           +  RX_orig_addr = the originator address of the current
              message, AND;

           +  RX_seq_number = the sequence number of the current
              message;

           then the current message MUST be silently discarded.

       2.  Otherwise:

           1.  Create a Received Tuple in the Received Set for the
               receiving interface with:

               -  RX_type := the Message Type of the current message;

               -  RX_orig_addr := originator address of the current
                  message;

               -  RX_seq_number := sequence number of the current
                  message;

               -  RX_time := current time + RX_HOLD_TIME.

           2.  If a Forwarded Tuple exists with:

               -  F_type = the Message Type of the current message, AND;

               -  F_orig_addr = the originator address of the current
                  message, AND;

               -  F_seq_number = the sequence number of the current
                  message.

               then the current message MUST be silently discarded.

           3.  Otherwise if the sending address matches (taking account
               of any address prefix) any address in an RY_neighbor_iface_addr
               L_neighbor_iface_addr_list of a Link Tuple in the
               Relay Link
               Set for the receiving interface, OLSRv2 interface which has L_status
               = SYMMETRIC and whose corresponding Neighbor Tuple has
               N_mpr_selector = true, then:

               1.  Create a Forwarded Tuple with:

                   o  F_type := the Message Type of the current message;

                   o  F_orig_addr := originator address of the current
                      message;

                   o  F_seq_number := sequence number of the current
                      message;

                   o  F_time := current time + F_HOLD_TIME.

               2.  The Message Header of the current message is modified
                   by:

                   o  if present, decrement <msg-hop-limit> in the
                      Message Header by 1, AND;

                   o  if present, increment <msg-hop-count> in the
                      Message Header by 1.

               3.  For each OLSRv2 interface of the router, include the
                   message in a packet to be transmitted on that OLSRv2
                   interface, as described in Section 8.  This packet
                   MAY contain other forwarded messages and/or messages
                   generated by this router, including by other
                   protocols using [RFC5444].  Forwarded messages MAY be
                   jittered as described in [RFC5148].  The value of
                   MAXJITTER used in jittering a forwarded message MAY
                   be based on information in that message (in
                   particular any INTERVAL_TIME or VALIDITY_TIME TLVs in
                   that message) or otherwise SHOULD be with a maximum
                   delay of F_MAXJITTER.  A router MAY modify the jitter
                   applied to a message in order to more efficiently
                   combine messages in packets, as long as the maximum
                   jitter is not exceeded.

8.  Packets and Messages

   The packet and message format used by OLSRv2 this protocol is defined in
   [RFC5444].  Except as otherwise noted, options defined in [RFC5444]
   may be freely used, in particular alternative formats defined by
   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
   message originator address and/or TLVs to these messages when sent
   over OLSRv2 interfaces, and processes these HELLO messages,
   subsequent to messages after
   their processing by NHDP. NHDP, as permitted by [NHDP].

   This protocol defines and owns the TC Message Type.  Extensions to OLSRv2
   this protocol MAY define additional additions to TC messages.  These MAY include
   new Message TLVs and/or Address Block TLVs.  Extensions MAY also
   include new Messsage Types to be handled similarly to TC messages.
   See Section 18.

   Routers using OLSRv2 this protocol exchange information through messages.
   One or more messages sent by a router at the same time SHOULD be
   combined into a single packet. 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
   [RFC5444], Message Types and TLVs specific to OLSRv2. this protocol.  All
   references in this specification to TLVs that do not indicate a type
   extension, assume Type Extension = 0.  TLVs in processed messages
   with a type extension which is neither zero as so assumed, nor a
   specifically indicated non-zero type extension, are ignored.

8.1.  HELLO Messages

   A HELLO message in OLSRv2 is generated as specified in [NHDP].  In addition, an OLSRv2 a
   router using this protocol MUST be able to modify add information to such
   messages, prior to these being sent on an OLSRv2 interface, as
   permitted by [NHDP], so that such all HELLO
   messages: messages sent on an OLSRv2
   interface:

   o  MUST include TLV(s) with Type := MPR associated with all addresses
      that:

      * allow a message originator address to be determined.  This
      will usually use the message's <msg-orig-addr> element as defined
      in [RFC5444].  There are included two permitted exceptions when the router
      MAY omit a <msg-orig-addr> element, but an originator address of
      the message is still correctly defined:

      *  If the message contains only a single local interface address,
         and that address is equal to this router's originator address,
         then that local interface address is the message originator
         address.

      *  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 HELLO
         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; AND

      *  are included in a Neighbor Tuple SYMMETRIC, include
      TLV(s) with N_mpr = true. 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
      other addresses.

   o  MAY include a message TLV with Type := MPR_WILLING, indicating the
      router's willingness to be selected as an MPR.

   An OLSRv2 router using this protocol MUST also be able to process access any
   incoming HELLO message received on an OLSRv2 interface, subsequent to
   the processing specified in [NHDP], as permitted by [NHDP].

8.1.1.  HELLO Message TLVs

   In a HELLO message, a router MUST include an MPR_WILLING Message TLV
   as specified in Table 1, unless WILLINGNESS = WILL_DEFAULT (in which
   case it MAY be included).  A router MUST NOT include more than one
   MPR_WILLING Message TLV.

   +-------------+--------------+--------------------------------------+
   |     Type    | Value Length | Value                                |
   +-------------+--------------+--------------------------------------+
   | MPR_WILLING |    1 octet   | Router parameter WILLINGNESS; unused |
   |             |              | bits (based on the maximum           |
   |             |              | willingness value WILL_ALWAYS) are   |
   |             |              | RESERVED and SHOULD be set to zero.  |
   +-------------+--------------+--------------------------------------+

                    Table 1 1: MPR_WILLING TLV definition

   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
   WILL_DEFAULT.

8.1.2.  HELLO Message Address Block TLVs

   In a HELLO message, a router MAY include MPR Address Block TLV(s) as
   specified in Table 2.

                      +------+--------------+-------+
                      | Type | Value Length | Value |
                      +------+--------------+-------+
                      |  MPR |   0 octets   | None. |
                      +------+--------------+-------+

                        Table 2 2: MPR TLV definition

8.2.  TC Messages

   A TC message MUST contain:

   o  <msg-orig-addr>,  A message originator address, using the message's <msg-orig-addr>
      element as defined in [RFC5444].

   o  <msg-seq-num> and <msg-hop-limit> elements in its
      Message Header, elements, as specified in
      [RFC5444].

   o  A <msg-hop-count> element in its Message Header if the message
      contains a TLV with either Type = VALIDITY_TIME or Type =
      INTERVAL_TIME indicating more than one time value according to
      distance.  (A TC message MAY contain <msg-hop-count> even if it
      does not need to.)

   o  A single Message TLV with Type := CONT_SEQ_NUM, and Type Extension
      := COMPLETE or Type Extension := INCOMPLETE, as specified in
      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
      [RFC5497].  The options included in [RFC5497] for representing
      zero and infinite times MUST NOT be used.

   o  All of the router's addresses.  These MUST be included in  If the
      message's Address Blocks, unless:

      * TC message is complete, all addresses which are the router has a single interface, with
      N_orig_addr of a single address Neighbor Tuple with
         maximum prefix length; AND

      *  that address is the router's originator address.

      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) N_advertised = true, each
      associated with a TLV with Type := LOCAL_IF = NBR_ADDR_TYPE, and Value := UNSPEC_IF =
      ORIGINATOR, or with Value = ROUTABLE_ORIG if also to be associated
      with all of Value = ROUTABLE, see Section 8.2.2.  If the router's addresses. 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 routable addresses which are in
      the Advertised
      Address Set 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 all addresses in the Local Attached Network Set,
      the latter (only) Value = ROUTABLE, or with Value = ROUTABLE_ORIG
      if also to be associated GATEWAY Address Block TLV(s), as
      specified in with Value = ORIGINATOR, see
      Section 8.2.2.

   A  If the TC message is incomplete then any such
      addresses MAY contain: be included; if any such addresses are included then
      this MUST be with the appropriate associated TLV(s).

   o  If the TC message is incomplete, any addresses in the Advertised
      Address Set and any complete, all addresses in which are the
      AL_net_addr of a Local Attached Network Set,
      the latter (only) with Tuple.  Each such address
      MUST be associated GATEWAY Address Block TLV(s), with a TLV with Type = GATEWAY, and Value =
      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:

   o  A Message TLV with Type := INTERVAL_TIME, as specified in
      [RFC5497].  The options included in [RFC5497] for representing
      zero and infinite times MUST NOT be used.

8.2.1.  TC Message TLVs

   In a each TC message, message which contains any addresses associated with a TLV
   with Type = NBR_ADDR_TYPE or Type = GATEWAY, a router MUST include a
   single CONT_SEQ_NUM Message TLV, as specified in Table 3, and with
   Type Extension = COMPLETE or Type Extension = INCOMPLETE, according
   to whether the TC message is complete or incomplete.

   +--------------+--------------+-------------------------------------+
   |     Type     | Value Length | Value                               |
   +--------------+--------------+-------------------------------------+
   | CONT_SEQ_NUM |   2 octets   | The ANSN contained in the Neighbor  |
   |              |              | Advertised Neighbor Set. Information Base.                   |
   +--------------+--------------+-------------------------------------+

                   Table 3 3: CONT_SEQ_NUM TLV definition

8.2.2.  TC Message Address Block TLVs

   In a TC message, a router MAY include GATEWAY 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
   specified in Table 5.

     +---------+--------------+-------------------------------------+
     |   Type  | Value Length | Value                               |
     +---------+--------------+-------------------------------------+
     | GATEWAY |    1 octet   | Number of hops to attached network. |
     +---------+--------------+-------------------------------------+

                                  Table 4

   GATEWAY Address Block TLV(s) 5

   All addresses included in a TC message according to this
   specification MUST be associated with all attached
   network addresses, and MUST NOT be associated either at least one TLV with any other
   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

   An OLSRv2 HELLO message is composed and generated as defined in [NHDP], with
   extended by the following additions:

   o  A Message TLV with Type := MPR_WILLING and Value := WILLINGNESS
      MUST be included, unless WILLINGNESS = WILL_DEFAULT (in which case
      it MAY be included).

   o  For each address which is included in being added to the HELLO message with by this
   protocol before being sent over an
      associated TLV with Type = LINK_STATUS and Value = SYMMETRIC, and
      is of an MPR (i.e. the address 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 N_neighbor_addr_list router that
         generated the HELLO message has only one interface address, and
         will use that as the sending address of a 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
      MUST be included, unless WILLINGNESS = WILL_DEFAULT (in which case
      it MAY be included).

   o  For each Neighbor Tuple with N_mpr = true), that address true, and for which one or
      more addresses in its N_neighbor_addr_list are included with an
      associated TLV with Type = LINK_STATUS and Value = SYMMETRIC, at
      least one of these addresses (including a different copy of that
      address, in the same or a different Address Block) MUST be
      associated with an Address Block TLV with Type := MPR.

   o  For each address which is included in the message and is  Note that
      other addresses (which do not meet this specification) MUST NOT be
      associated with a an Address Block TLV with Type = LINK_STATUS and Value =
      SYMMETRIC, or is not of an MPR (i.e. the address is not in the
      N_neighbor_addr_list of a Neighbor Tuple with N_mpr = true), MPR, but that
      more than one address (including different copies of that address, in from the same
      or different Address Blocks) MUST NOT qualifying
      N_neighbor_addr_list MAY be associated with an Address Block TLV
      with Type := MPR.

   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
      subject to the same constraints.

9.1.  HELLO Message: Transmission

   HELLO messages are included in packets as specified in [RFC5444].
   These packets may contain other messages, including TC messages.

10.  HELLO Message Processing

   All HELLO message processing, including determination of whether a
   message is invalid, considers only TLVs with Type Extension = 0.
   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 =
   MPR_WILLING and Type Extension = 0.

   In addition to the reasons specified in [NHDP], [NHDP] for discarding a HELLO
   message on reception, a HELLO message MUST NOT: be discarded before
   processing by [NHDP] or this specification if it:

   o  Have  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  Has a message originator address, or any address associated with a
      TLV with Type = LOCAL_IF, that the receiving router has recorded
      as:

      *  its originator address, OR;

      *  as the O_orig_addr in an Originator Tuple, OR;

      *  in an I_local_iface_addr_list in a Local Interface Tuple, OR;

      *  as the IR_local_iface_addr in a Removed Interface Address
         Tuple, OR;

      *  as the AL_net_addr in a Local Attached Network Tuple.

      Note that some of these cases are already excluded by [NHDP].

   o  Includes any address associated with a TLV with Type = LINK_STATUS
      or Type = OTHER_NEIGHB that is also the message's originator
      address.

   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) which is not also associated with the single Value SYMMETRIC by a
      TLV with Type = LINK_STATUS
      or Type and Value = OTHER_NEIGHB.

   Such a HELLO message MAY be discarded before processing.  If it is
   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. SYMMETRIC.

   HELLO messages are first processed as specified in [NHDP].  The
   router MUST identify the  That
   processing includes identifying (or creating) a Neighbor Tuple
   corresponding to the originator of the HELLO message (the "current
   Neighbor Tuple") and
   update its Tuple").  After this, the following MUST be performed:

   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:

       1.  Remove any other Neighbor Tuples with N_orig_addr = message
           originator address, taking any consequent action (including
           removing one or more Link Tuples) as specified in [NHDP].

       2.  The current Neighbor Tuple is then updated according to:

           1.  N_orig_addr := message originator address;

           2.  Update N_willingness as described in Section 10.1 and its 10.1;

           3.  Update N_mpr_selector as described in Section 10.2.  Following these,

   2.  If there are any changes to the
   router MUST also router's Information Bases, then
       perform the processing defined in Section 10.3. 13.

10.1.  Updating Willingness

   N_willingness in the current Neighbor Tuple is updated as follows:

   1.  If the HELLO message contains a Message TLV with Type =
       MPR_WILLING then N_willingness := the Value of that TLV;

   2.  Otherwise, N_willingness := WILL_DEFAULT.

10.2.  Updating MPR Selectors

   N_mpr_selector is updated as follows:

   1.  If a router finds any of its local interface addresses with an associated
       TLV with Type = (i.e.,
       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
       originator originating router has selected the
       receiving router as an MPR) then, for the current Neighbor Tuple:

       *  N_mpr_selector := true

   2.  Otherwise,  Otherwise (i.e., if no such address and TLV were found) if a
       router finds any of its own local interface addresses with an
       associated TLV with Type = LINK_STATUS and Value = SYMMETRIC in
       the HELLO message, then for the current Neighbor Tuple:

       *  N_mpr_selector := false

10.3.  Symmetric 1-Hop and 2-Hop Neighborhood Changes

   A router MUST also perform the following:

   1.  If N_symmetric of a Neighbor Tuple changes from true to false,
       for that Neighbor Tuple:

       *  N_mpr_selector  N_advertised := false

   2.  The set of MPRs of a

11.  TC Message Generation

   A router MUST be recalculated if:

       *  a Link Tuple is added with L_status = SYMMETRIC, OR;

       *  a Link Tuple one or more OLSRv2 interfaces, and with L_status = SYMMETRIC is removed, OR;

       *  a Link Tuple any Neighbor
   Tuples with L_status = SYMMETRIC changes to having
          L_status N_advertised = HEARD true, 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 non-empty Local Attached
   Network Set MUST generate TC messages.  A router which does not have
   such information to any other value, OR;

       *  the N_willingness of advertise SHOULD also generate "empty" TC
   messages for a Neighbor Tuple with N_symmetric = true
          and N_mpr = true changes to WILL_NEVER from any other value,
          OR;

       *  the N_willingness of period A_HOLD_TIME after it last generated a Neighbor Tuple with N_symmetric = true non-empty
   TC message.  TC messages (non-empty and N_mpr = false changes to WILL_ALWAYS from any other value.

   3.  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.  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

   A router with one or more OLSRv2 interfaces, and with a non-empty
   Advertised Neighbor Set or a non-empty Local Attached Network Set
   MUST generate TC messages.  A router with an empty Advertised
   Neighbor Set and empty Local Attached Network Set SHOULD also
   generate "empty" TC messages for a period A_HOLD_TIME after it last
   generated a non-empty TC message.  TC messages (non-empty and empty)
   are generated according empty) are generated
   according to the following:

   1.  The message originator address MUST be set to the router's originator
       address.

   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
       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
       in TC messages, see Section 5.8.

   4.  The message MUST contain a Message TLV with Type := CONT_SEQ_NUM
       and Value := ANSN from the Advertised Neighbor Set. Information Base.  If the TC
       message is complete then this Message TLV MUST have Type
       Extension := COMPLETE, otherwise it MUST have Type Extension :=
       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 :=
       VALIDITY_TIME, as specified in [RFC5497].  If all TC messages are
       sent with the same hop limit then this TLV MUST have Value :=
       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
       times which vary with the number of hops distance appropriate to
       the chosen pattern of TC message hop limits, as specified in
       [RFC5497], these times SHOULD be appropriate multiples of
       T_HOLD_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
       same hop limit then this TLV MUST have Value := TC_INTERVAL.  If
       TC messages are sent with different hop limits, then this TLV
       MUST specify times which vary with the number of hops distance
       appropriate to the chosen pattern of TC message hop limits, as
       specified in [RFC5497], these times SHOULD be appropriate
       multiples of TC_INTERVAL.

   7.  Unless the router has a single interface, with a single address
       with maximum prefix length, and that address is the router's
       originator address, the  A complete message MUST contain all of the router's
       addresses (i.e. all addresses in include, and an I_local_iface_addr_list) incomplete message MAY
       include, in its Address Blocks.

   8.  All addresses of the router's interfaces that are included Blocks:

       1.  N_orig_addr in an
       Address Block MUST each be Neighbor Tuple with N_advertised = true,
           associated with a TLV with Type :=
       LOCAL_IF NBR_ADDR_TYPE and Value := UNSPEC_IF.

   9.  A complete message MUST include, and
           ORIGINATOR (or Value := ROUTABLE_ORIG if also to be
           associated with Value = ROUTABLE).

       2.  Each routable address in an incomplete message MAY
       include, N_neighbor_addr_list in its Address Blocks:

       1.  Each A_neighbor_addr from the Advertised each
           Neighbor Set;

       2. 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 from in each Local Attached Neighbor Tuple, each
           associated with a TLV with Type := GATEWAY and Value :=
           AL_dist.

11.1.  TC Message: Message Transmission

   Complete TC messages are generated and transmitted periodically on
   all OLSRv2 interfaces, with a default interval between two
   consecutive TC transmissions by the same router of TC_INTERVAL.

   TC messages MAY be generated in response to a change of contents, in the
   information which they are to advertise, indicated by a change in
   ANSN.  In this case a router MAY send a complete TC message, and if
   so MAY re-start its TC message schedule.  Alternatively a router MAY
   send an incomplete TC message with at least the new content newly advertised
   addresses (i.e. not previously, but now, an N_orig_addr or an
   N_neighbor_addr_list in a Neighbor Tuple with N_advertised = true, or
   in an AL_net_addr) in its Address Blocks. 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, advertised
   addresses, a router must respect a minimum interval of
   TC_MIN_INTERVAL between generated TC messages.  Sending an incomplete
   TC message MUST NOT cause the interval between complete TC messages
   to be increased, and thus a router MUST NOT send an incomplete TC
   message if within TC_MIN_INTERVAL of the next scheduled complete TC
   message.

   The generation of TC messages, whether scheduled or triggered by a
   change of contents MAY be jittered as described in [RFC5148].  The
   values of MAXJITTER used SHOULD be:

   o  TP_MAXJITTER for periodic TC message generation;

   o  TT_MAXJITTER for responsive TC message generation.

   TC messages are included in packets as specified in [RFC5444].  These
   packets MAY contain other messages, including HELLO messages and TC
   messages with different originator addresses.  TC messages are
   forwarded according to the specification in Section 7.3.

12.  TC Message Processing

   On receiving a TC message, a router MUST first check if the message
   is invalid for processing by this router, as defined in Section 12.1.
   Otherwise the receiving router MUST update its appropriate Interface
   Information Base and its Router Information Base as specified in
   Section 12.2.

   All TC message processing, including determination of whether a
   message is invalid, unless otherwise noted considers only TLVs with
   Type Extension = 0.  TLVs with any other type extension (or any
   unmentioned type extension when other type extensions are considered)
   are ignored.  All references to, for example, a TLV with Type =
   VALIDITY_TIME refer to a TLV with Type = VALIDITY_TIME and Type
   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

   A received TC message is invalid for processing by this router if any
   of the following conditions are true.
   message:

   o  The Message Header does  Does not include an a message originator address, a message sequence
      number, and a hop limit.

   o  The Message Header  Does not include a hop count, and contains a multi-value TLV with
      Type = VALIDITY_TIME or Type == = INTERVAL_TIME, as defined in
      [RFC5497].

   o  The message does  Does not have a single exactly one TLV with Type = VALIDITY_TIME in its
      Message TLV Block.

   o  The message has  Has more than one TLV with Type = INTERVAL_TIME in its Message TLV
      Block.

   o  The message does  Does not have a TLV with Type = CONT_SEQ_NUM and Type Extension =
      COMPLETE or Type Extension = INCOMPLETE in its Message TLV Block. Block,
      and contains at least one address associated with a TLV with Type
      = NBR_ADDR_TYPE or Type = GATEWAY.

   o  The message has  Has more than one TLV with Type = CONT_SEQ_NUM and Type Extension
      = COMPLETE or Type Extension = INCOMPLETE in its Message TLV Block, and these do not have the same type extension
      and the same Value.
      Block.

   o  The  Has a message has any Address Block TLV(s) with Type = LOCAL_IF and originator address, or any single Value(s) which are not equal to UNSPEC_IF.

   o  Any address associated with a
      TLV with Type = LOCAL_IF is one of NBR_ADDR_TYPE or Type = GATEWAY, that the
      receiving router's current or recently used addresses (i.e. is
      in any I_local_iface_addr_list in router has recorded as:

      *  its originator address, OR;

      *  as the O_orig_addr in an Originator Tuple, OR;

      *  in an I_local_iface_addr_list in a Local Interface Set or is
      equal to any Tuple, OR;

      *  the IR_local_iface_addr in the a Removed Interface Address
      Set). Tuple.

   o  Any  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) is associated with more than one single
      Value by 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
   message is invalid.  An invalid message MUST be silently discarded,
   without updating the router's Information Bases.

12.2.  Initial  TC Message Processing Definitions

   When, according to Section 7.2, a TC message is to be "processed
   according to its type", this means that:

   o  If the TC message contains a Message TLV with Type = CONT_SEQ_NUM
      and Type Extension = COMPLETE, then processing according to
      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
      and Type Extension = INCOMPLETE, then only processing according to
      Section 12.3 is carried out.

   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
      the TC message according to the specification in [RFC5497].  All
      information in the TC message has the same validity time.

   o  "ANSN"  "received ANSN" is defined as being the Value of a Message TLV
      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
      Section 18. 17.

12.3.  Initial TC Message Processing

   The TC message is processed as follows:

   1.  The Advertising Remote Router Set is updated according to
       Section 12.3.1; if 12.3.1.  If the TC message is indicated as discarded in
       that processing then the following steps are not carried out.

   2.  The Router Topology Set is updated according to Section 12.3.2.

   3.  The Routable Address Topology Set is updated according to
       Section 12.3.3.

   4.  The Attached Network Set is updated according to Section 12.3.3. 12.3.4.

12.3.1.  Populating the Advertising Remote Router Set

   The router MUST update its Advertising Remote Router Set as follows:

   1.  If there is an Advertising Remote Router Tuple with:

       *  AR_orig_addr = message originator address; AND

       *  AR_seq_number > received ANSN

       then the TC message MUST be discarded.

   2.  Otherwise:

       1.  If there is no Advertising Remote Router Tuple such that:

           +  AR_orig_addr = message originator address;

           then create an Advertising Remote Router Tuple with:

           +  AR_orig_addr := message originator address.

       2.  This Advertising Remote Router Tuple (existing or new, the
           "current tuple") new) is
           then modified as follows:

           +  AR_seq_number := received ANSN;

           +  AR_time := current time + validity time.

           +  AR_addr_list := sending address list

       3.

12.3.2.  Populating the Router Topology Set

   The router MUST update its Router Topology Set as follows:

   1.  For each other Advertising Remote Router Tuple (with a
           different AR_orig_addr, the "other tuple") whose AR_addr_list
           contains any address (henceforth advertised address) in an Address
       Block that has an associated TLV with Type = NBR_ADDR_TYPE and
       Value = ORIGINATOR or Value = ROUTABLE_ORIG, perform the AR_addr_list of the current
           tuple:
       following processing:

       1.  remove all  If there is no Router Topology Tuples with T_orig_addr Tuple such that:

           +  TR_from_orig_addr =
               AR_orig_addr of the other tuple;

           2.  remove all Attached Network Tuples with AN_orig_addr message originator address; AND

           +  TR_to_orig_addr =
               AR_orig_addr of the other tuple;

           3.  remove the other tuple.

12.3.2. advertised address

           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
       Block that does not have has an associated TLV with Type = LOCAL_IF, NBR_ADDR_TYPE and
       Value = ROUTABLE or an associated TLV with Type Value = GATEWAY: ROUTABLE_ORIG, perform the following
       processing:

       1.  If there is no Routable Address Topology Tuple such that:

           +  T_dest_addr  TA_from_orig_addr = advertised message originator address; AND

           +  T_orig_addr  TA_dest_addr = originator advertised address

           then create a new Routable Address Topology Tuple with:

           +  T_dest_addr  TA_from_orig_addr := advertised message originator address;

           +  T_orig_addr  TA_dest_addr := originator advertised address.

       2.  This Routable Address Topology Tuple (existing or new) is
           then modified as follows:

           +  T_seq_number  TA_seq_number := received ANSN;

           +  T_time  TA_time := current time + validity time.

12.3.3.

12.3.4.  Populating the Attached Network Set

   The router MUST update its Attached Network Set as follows:

   1.  For each address (henceforth network advertised address) in an Address
       Block that does not have has an associated TLV with Type = LOCAL_IF, GATEWAY, and
       does have is not
       an associated TLV with Type = GATEWAY: AL_net_addr in a Local Attached Network Tuple, perform the
       following processing:

       1.  If there is no Attached Network Tuple such that:

           +  AN_net_addr = network address; AND

           +  AN_orig_addr = message originator address

           then create a new Attached Network Tuple with:

           +  AN_net_addr := network address;

           +  AN_orig_addr := message originator address address.

       2.  This Attached Network Tuple (existing or new) is then
           modified as follows:

           +  AN_dist := the Value of the associated GATEWAY TLV;

           +  AN_seq_number := received ANSN;

           +  AN_time := current time + validity time.

12.4.  Completing TC Message Processing

   The TC message is processed as follows:

   1.  The Router Topology Set is updated according to Section 12.4.1.

   2.  The Routable Address Topology Set is updated according to
       Section 12.4.2.

   3.  The Attached Network Set is updated according to Section 12.4.2. 12.4.3.

12.4.1.  Purging the Router Topology Set

   The Router Topology Set MUST be updated as follows:

   1.  Any Router Topology Tuples with:

       *  T_orig_addr  TR_from_orig_addr = message originator address; AND

       *  T_seq_number  TR_seq_number < received ANSN

       MUST be removed.

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:

   1.  Any Attached Network Tuples with:

       *  AN_orig_addr = message originator address; AND

       *  AN_seq_number < received ANSN

       MUST be removed.

13.  Information Base Changes

   1.

   The Originator Set changes described in the Local Information Base following sections MUST be updated carried out
   when the router any Information Base changes originator address. as indicated.

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

       then create an Originator Tuple with:

       *  O_orig_addr := old originator address

       This

       The Originator Tuple (existing or new) with:

       *  O_orig_addr = new originator address

       is then modified as follows:

       *  O_time := current time + O_HOLD_TIME

   2.  The Advertised

13.2.  Neighbor Set State Changes

   The N_mpr_selector and N_advertised flags in the Topology Information Base Neighbor Tuples MUST be changed when
   maintained according to the Neighbor Set changes.  The following changes
       are required: rules:

   1.  If an address in an N_neighbor_addr_list in a Neighbor Tuple
           is removed (including when that Neighbor Tuple is removed)
           and that address is also an A_neighbor_addr in an Advertised
           Neighbor Tuple, N_symmetric = false, then that Advertised Neighbor Tuple MUST be
           removed. N_mpr_selector = false and
       N_advertised = false.

   2.  If an address is added to an N_neighbor_addr_list in a
           Neighbor Tuple with N_mpr_selector = true, then N_advertised = true.

   3.  In other cases (i.e.  N_symmetric = true (including when
           such and N_mpr_selector =
       false) a Neighbor Tuple is added) router MAY select N_advertised = true or N_advertised =
       false.  The more neighbors that are advertised, the larger TC
       messages become, but the more redundancy is available for each address in an
           N_neighbor_addr_list
       routing.  A router SHOULD consider the nature of its network in
       making such a Neighbor Tuple whose N_mpr_selector
           has changed from false to true, decision, and that address is not
           already an A_neighbor_addr SHOULD avoid unnecessary changes in an Advertised Neighbor Tuple,
           then an Advertised Neighbor Tuple MUST
       advertising status, which may result both in additional TC
       messages having to be added sent by its neighbors, and in unnecessary
       changes to the
           Advertised Neighbor Set with A_neighbor_addr equal routing, which will have similar effects to that
           address.

       Other other
       forms of topology changes to in the MANET.

13.3.  Advertised Neighbor Set MAY be made when Changes

   The router MUST increment the
       Neighbor Set changes, ANSN in particular if the N_mpr_selector of a Neighbor Information Base
   whenever:

   1.  Any 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 its N_advertised value.

   2.  N_orig_addr is changed, or any routable address is added to or
       removed from any Neighbor Tuple MAY be removed. with N_advertised = true.

   3.  There is any change to the Local Attached Network Set.

13.4.  Advertising Remote Router Tuple Expires

   The Router Topology Set, the Routable Address Topology Set and the
   Attached Network Set in the Topology
       Information Base 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:

           +  T_orig_addr

       *  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.

14.  Selecting MPRs

   Each router MUST select, from among its willing

13.5.  Neighborhood Changes and MPR Updates

   The set of symmetric 1-hop
   neighbors, a subset of routers neighbors selected as MPRs.  MPRs are used to flood
   control messages from a router into the network, while reducing the
   number of retransmissions that will occur in a region.  Thus, the
   concept of MPR flooding is an optimization of a classical flooding
   mechanism. MPRs MAY also be used to reduce MUST satisfy
   the shared topology
   information conditions defined in the network.  Consequently, while it is not essential
   that the Section 14.  To ensure this:

   1.  The set of MPRs is minimal, keeping the number of MPRs small
   ensures that the overhead of OLSRv2 is kept at a minimum.

   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
   MUST include all symmetric 1-hop neighbors be recalculated if:

       *  a Link Tuple is added with willingness
   WILL_ALWAYS.  Only this overall set of MPRs L_status = SYMMETRIC, OR;

       *  a Link Tuple with L_status = SYMMETRIC is relevant, the recorded
   and used MPR relationship is one of routers, not interfaces.  Routers
   MAY select their MPRs by any process which satisfies the conditions
   which follow.  Routers can freely interoperate whether they use the
   same removed, OR;

       *  a Link Tuple with L_status = SYMMETRIC changes to having
          L_status = HEARD or different MPR selection algorithms.

   For each OLSRv2 interface L_status = LOST, OR;

       *  a router MUST select Link Tuple with L_status = HEARD or L_status = LOST changes
          to having L_status = SYMMETRIC, OR;

       *  a set of MPRs.  This
   set MUST have 2-Hop Tuple is added or removed, OR;

       *  the properties that:

   o  All N_willingness of a Neighbor Tuple with N_symmetric = true
          changes from WILL_NEVER to any other value, OR;

       *  the selected MPRs are willing symmetric 1-hop neighbors,
      AND;

   o  If the selecting router sends N_willingness of a message on that OLSRv2 interface, Neighbor Tuple with N_symmetric = true
          and that message is successfully forwarded by all of N_mpr = true changes to WILL_NEVER from any other value,
          OR;

       *  the selected
      MPRs for that interface, then all symmetric strict 2-hop neighbors N_willingness of the selecting router through that OLSRv2 interface will receive
      that message on a symmetric link.

   Note that it is always possible Neighbor Tuple with N_symmetric = true
          and N_mpr = false changes to select a valid set of MPRs.  The WILL_ALWAYS from any other value.

   2.  Otherwise, the set of all willing symmetric 1-hop neighbors MPRs of a router is a
   (maximal) valid set MAY be recalculated if the
       N_willingness of MPRs for that router.  However a router SHOULD
   NOT select a symmetric 1-hop neighbor Neighbor Tuple with Willingness != WILL_ALWAYS
   as N_symmetric = true changes
       in any other way; it SHOULD be recalculated if N_mpr = false and
       this is an MPR increase in N_willingness or if there are no symmetric strict 2-hop neighbors with N_mpr = true and this
       is a
   symmetric link to that symmetric 1-hop neighbor.  Thus decrease in N_willingness.

   If the set of MPRs of a router with
   no symmetric 1-hop neighbors with willingness WILL_ALWAYS and with no
   symmetric strict 2-hop neighbors SHOULD NOT select any MPRs.

   A router MAY select its MPRs for each OLSRv2 interface independently,
   or it MAY coordinate its MPR selections across its OLSRv2 interfaces,
   as long as the required condition is satisfied for each OLSRv2
   interface.  Each router MAY select its MPRs independently from the
   MPR selection by other routers, or it MAY, for example, give
   preference to routers recalculated, this MUST be as
   described in Section 14.  Before that either are, or calculation, the N_mpr of all
   Neighbor Tuples are not, already selected
   as MPRs by other routers.

   When selecting MPRs for each OLSRv2 interface independently, this set false (although the previous values of N_mpr
   MAY be done using information from used by an algorithm that minimises changes to the Link Set and 2-Hop Set set of
   MPRs).  After that
   OLSRv2 interface, and 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 of the router (specifically
   the N_willingness elements). Updates

   The selection of MPRs (overall, not per OLSRv2 interface) is recorded Routing Set MUST be updated, as described in Section 15 when
   changes in the Neighbor Set of Local Information Base, the router (using Neighborhood Information
   Base or the N_mpr elements).  A
   selected MPR MUST be Topology Information Base indicate a willing symmetric 1-hop neighbor (i.e. the
   corresponding N_symmetric = true, and change of the corresponding N_willingness
   != WILL_NEVER).

   A router MUST recalculate its MPRs whenever known
   symmetric links and/or attached networks in the currently selected
   set of MPRs does not still satisfy MANET, hence changing
   the required conditions. Topology Graph.  It MAY
   recalculate its MPRs is sufficient to consider only changes which
   affect at least one of:

   o  The Local Interface Set, if the current set of MPRs change removes any address in an
      I_local_iface_addr_list.  In this case, unless the OLSRv2
      interface is still valid, but
   could removed, it may not be necessary to do more efficient.  It 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 sufficient also an AN_net_addr.  In this case it may not be
      necessary to recalculate a router's
   MPRs when there is a change do more than add and remove Routing Tuples with
      R_dest_addr equal to any of the router's that AN_net_addr.

   o  The Link Sets
   affecting the symmetry Set of any link (addition OLSRv2 interface, and to consider only Link
      Tuples which have, or just had, L_status = SYMMETRIC (including
      removal of a such Link
   Tuple with L_status = SYMMETRIC, or change Tuples).

   o  The Neighbor Set of any L_status the router, and to consider only Neighbor
      Tuples that have, or from
   SYMMETRIC), any change to 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 router's 2-Hop Sets, or a change Routing Set.

   o  The Router Topology Set 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 router.

   o  The Routable Address Topology Set of MPRs that satisfies the required
   conditions is given in Appendix B.

15.  Populating Derived Sets router.

   o  The Relay Sets and the Advertised Neighbor Attached Network Set of a the router.

14.  Selecting MPRs

   Each router are
   denoted derived sets, since updates to MUST select, from among its willing symmetric 1-hop
   neighbors, a subset of these sets are not directly routers as MPRs.  Only MPRs forward
   control messages flooded through the MANET, thus effecting a
   function flooding
   reduction, an optimization of message exchanges, but rather are derived from updates the classical flooding mechanism, known
   as MPR flooding.  MPRs MAY also be used to
   other sets, effect a topology
   reduction in particular to the MPR selector status MANET.  Consequently, while it is not essential that
   the set of other routers
   recorded in MPRs is minimal, keeping the Neighbor Set.

15.1.  Populating number of MPRs small ensures
   that the Relay Set

   The Relay Set overhead is kept at a minimum.

   A router MUST select MPRs for an OLSRv2 interface contains the set each of its OLSRv2
   interface addresses interfaces, but then
   forms the union of those symmetric 1-hop neighbors for which this
   OLSRv2 interface is to relay broadcast traffic.  This sets as its single set MUST
   contain only addresses of OLSRv2 interfaces with which this OLSRv2
   interface has a symmetric link. MPRs.  This set union
   MUST include all such
   addresses of all such OLSRv2 interfaces of routers which are MPR
   selectors of symmetric 1-hop neighbors with willingness
   WILL_ALWAYS.  Only this router.

   The Relay Set for an OLSRv2 interface overall set of this router MPRs is thus created
   by:

   1.  For each Link Tuple in relevant, the Link Set for this OLSRv2 interface
       with L_status = SYMMETRIC, recorded
   and used MPR relationship is one of routers, not interfaces.  Routers
   MAY select their MPRs by any process which satisfies the corresponding Neighbor Tuple
       with N_neighbor_addr_list containing L_neighbor_iface_addr_list:

       1.  All addresses from L_neighbor_iface_addr_list MUST be
           included in conditions
   which follow.  Routers can freely interoperate whether they use the Relay Set of this
   same or different MPR selection algorithms.

   For each OLSRv2 interface if
           N_mpr_selector = true, and otherwise MAY be so included.

15.2.  Populating the Advertised Neighbor Set

   The Advertised Neighbor Set of a router contains all addresses MUST select a set of
   those MPRs.  This
   set MUST have the properties that:

   o  All of the selected MPRs are willing symmetric 1-hop neighbors to which neighbors,
      AND;

   o  If the selecting router advertises sends a link
   in its TC messages.  This set MUST include all addresses in message on that OLSRv2 interface,
      and that message is successfully forwarded by all MPR
   selector of this router.

   The Advertised Neighbor Set the selected
      MPRs for this that interface, then all symmetric strict 2-hop neighbors
      of the selecting router through that OLSRv2 interface will receive
      that message over a symmetric link.

   Note that it is thus created by:

   1.  For each Neighbor Tuple with N_symmetric = true:

       1.  All addresses from N_neighbor_addr_list MUST be included in
           the Advertised Neighbor Set if N_mpr_selector = true, and
           otherwise MAY be so included.

   Whenever address(es) are added always possible to or removed from the Advertised
   Neighbor Set, its ANSN MUST be incremented.

16.  Routing Set Calculation select a valid set of MPRs.  The Routing Set
   set of all willing symmetric 1-hop neighbors of a router is populated with Routing Tuples that
   represent paths from a
   (maximal) valid set of MPRs for that router.  However a router to all destinations in the network.
   These paths SHOULD
   NOT select a symmetric 1-hop neighbor with Willingness != WILL_ALWAYS
   as an MPR if there are calculated based on no symmetric strict 2-hop neighbors with a
   symmetric link to that symmetric 1-hop neighbor.  Thus a router with
   no symmetric 1-hop neighbors with willingness WILL_ALWAYS and with no
   symmetric strict 2-hop neighbors SHOULD NOT select any MPRs.

   A router MAY select its MPRs for each OLSRv2 interface independently,
   or it MAY coordinate its MPR selections across its OLSRv2 interfaces,
   as long as the Network Topology Graph, which required condition is constructed satisfied for each OLSRv2
   interface.  Each router MAY select its MPRs independently from information in the Information Bases, obtained
   via HELLO and TC message exchange.

16.1.  Network Topology Graph

   The Network Topology Graph is formed from
   MPR selection by other routers, or it MAY, for example, give
   preference to routers that either are, or are not, already selected
   as MPRs by other routers.

   When selecting MPRs for each OLSRv2 interface independently, this MAY
   be done using information from the
   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 Set of that
   OLSRv2 interface only, and the network in form Neighbor Set of a directed graph,
   containing the following arcs:

   o  Local symmetric links - all arcs X -> Y such that:

      *  X is an address in router
   (specifically the I_local_iface_addr_list of a Local
         Interface Tuple N_willingness elements).

   The selection of this router, AND;

      *  Y MPRs (overall, not per OLSRv2 interface) is an address recorded
   in the L_neighbor_iface_addr_list Neighbor Set of a Link
         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:

      *  Y is an address in router (using the L_neighbor_iface_addr_list of N_mpr elements).  A
   selected MPR MUST be a Link
         Tuple, in any of willing symmetric 1-hop neighbor (i.e. the router's Link Sets, which has L_status
   corresponding N_symmetric =
         SYMMETRIC, AND;

      * true, and the Neighbor Tuple with Y in its N_neighbor_addr_list has corresponding N_willingness
   != WILL_NEVER).

   A router MUST recalculate its MPRs whenever the currently selected
   set of MPRs does not equal to WILL_NEVER, AND;

      *  Z is still satisfy the N2_2hop_addr required conditions.  It MAY
   recalculate its MPRs if the current set of MPRs is still valid, but
   could be more efficient.  Sufficient conditions to recalculate a 2-Hop Tuple
   router's set of MPRs are given in Section 13.5.

   An example algorithm that creates a set of MPRs that satisfies the 2-Hop
   required conditions is given in Appendix A.

15.  Routing Set Calculation

   The Routing Set
         corresponding to the OLSRv2 interface of the chosen Link Set.

   o  Advertised symmetric links - all arcs U -> V such that there
      exists a Topology Tuple and a corresponding Advertising Remote
      Router Tuple (i.e. with AR_orig_addr = T_orig_addr) with:

      *  U router is populated with Routing Tuples that
   represent paths from that router to all destinations in the AR_addr_list of network.
   These paths are calculated based on the Advertising Remote Router
         Tuple, AND;

      *  V Network Topology Graph, which
   is constructed from information in the T_dest_addr of the Topology Tuple.

   o  Symmetric 1-hop neighbor addresses - all arcs Y -> W such that:

      *  Y is, Information Bases, obtained
   via HELLO and W is not, an address in TC message exchange.

   Changes to the
         L_neighbor_iface_addr_list of a Link Tuple, in Routing Set do not require any messages to be
   transmitted.  The state of the Routing Set SHOULD, however, be
   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.

15.1.  Network Topology Graph

   The Network Topology Graph is formed from information from the
   router's Local Interface Set, Link Sets, which has L_status = SYMMETRIC, AND;

      *  W Neighbor Set, Router
   Topology Set, Routable Address Topology Set and Y are included in Attached Network Set.
   The Network Topology Graph MAY also use information from the same N_neighbor_addr_list (i.e. router's
   2-Hop Sets.  The Network Topology Graph forms the
         one in router's
   topological view of the Neighbor Tuple whose N_neighbor_addr_list contains network in form of a directed graph.  The
   Network Topology Graph has a "backbone" (within which minimum
   distance routes will be constructed) containing the L_neighbor_iface_addr_list that includes Y). following edges:

   o  Attached network addresses - all arcs U  Edges X -> T such that there
      exists an Attached Network Tuple Y for all possible Y, and a corresponding Advertising
      Remote Router Tuple (i.e. with AR_orig_addr = AN_orig_addr) with: one X per Y, such that:

      *  U  Y is in the AR_addr_list N_orig_addr of the Advertising Remote Router a Neighbor Tuple, AND;

      *  T  N_orig_addr is not unknown;

      *  X is the AN_net_addr of the Attached Network Tuple.

   All links in the first three cases above have a hop count I_local_iface_addr_list of one, the
   symmetric 1-hop neighbor addresses have a hop count of zero, and the
   attached network addresses have Local Interface Tuple,
         AND;

      *  There is a hop count given by the appropriate
   value of AN_dist.

16.2.  Populating the Routing Set

   The Routing Set MUST contain the shortest paths for all destinations Link Tuple with L_status = SYMMETRIC such that this
         Neighbor Tuple and this Local Interface Tuple correspond to it.
         An address from all local OLSRv2 interfaces using the Network Topology Graph.
   This calculation MAY use any algorithm, including any means of
   choosing between paths of equal length.

   Using the notation of Section 16.1, each path will have as its first
   arc a local symmetric link X -> Y. There L_neighbor_iface_addr_list will be a path for each
   terminating Y, Z, V, W and T which can denoted R in
         this case.

      It SHOULD be connected preferred, where possible, to local OLSRv2
   address select R = S and X using from
      the indicated arcs.  The Local Interface Tuple corresponding Routing to the Link Tuple
   for this path will have: from
      which R was selected.

   o  R_dest_addr := the terminating Y, Z, V,  All edges W or T;

   o  R_next_iface_addr := -> U such that:

      *  W is the first arc's Y;

   o  R_dist := TR_from_orig_addr of a Router Topology Tuple, AND;

      *  U is the total hop count TR_to_orig_addr of the path;

   o  R_local_iface_addr := same Router Topology Tuple.

   The Network Topology Graph is further "decorated" with the first arc's X.

   An example algorithm for calculating following
   edges.  If an address S, V, Z or T equals an address Y or W, then the Routing Set of a router is
   given
   edge terminating in Appendix C.

16.3.  Routing Set Updates

   The Routing Set the address S, V, Z or T MUST NOT be updated when changes used in any
   path.

   o  Edges X -> S for all possible S, and one X per S, such that:

      *  S is in the Neighborhood
   Information Base or the Topology Information Base indicate a change N_neighbor_addr_list of the known symmetric links and/or attached networks a Neighbor Tuple, AND;

      *  X is in the MANET.
   It is sufficient to consider only changes which affect at least one
   of:

   o  The Link Set I_local_iface_addr_list of any OLSRv2 interface, and to consider only a Local Interface Tuple,
         AND;

      *  There is a Link
      Tuples which have, or just had, Tuple with L_status = SYMMETRIC (including
      removal of such Link Tuples).

   o  The that this
         Neighbor Set of the router, Tuple and this Local Interface Tuple correspond to consider only Neighbor
      Tuples that have, or just had, N_symmetric it.
         An address from L_neighbor_iface_addr_list will be denoted R in
         this case.

      It SHOULD be preferred, where possible, to select R = true.

   o  The 2-Hop Set of any OLSRv2 interface.

   o  The Advertising Remote Router Set of S and X from
      the router. Local Interface Tuple corresponding to the Link Tuple from
      which R was selected.

   o  The  All edges W -> V such that:

      *  W is the TA_from_orig_addr of a Routable Address Topology Set
         Tuple, AND;

      *  V is the TA_dest_addr of the router. same Routable Address Topology
         Tuple.

   o  The  All edges W -> T such that:

      *  W is the AN_orig_addr of an Attached Network Set Tuple, AND;
      *  T is the AN_net_addr of the router.

   Updates to same Attached Network Tuple.

   o  OPTIONALLY, all edges Y -> Z such that:

      *  Z is a routable address and is the Routing Set do not generate or trigger any messages to
   be transmitted.  The state N2_2hop_addr of a 2-Hop
         Tuple, AND;

      *  Y is the Routing Set SHOULD, however, N_orig_addr of the corresponding Neighbor Tuple, AND;

      *  This Neighbor Tuple has N_willingness not equal to WILL_NEVER.

      A path terminating with such an edge SHOULD NOT be
   reflected used in
      preference to any other path.

   Any part of the IP routing table by adding 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 removing entries 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 IP routing table as appropriate.

17.  Proposed Values appropriate value of AN_dist.

15.2.  Populating the Routing Set

   The Routing Set MUST contain the shortest paths for Parameters and Constants

   OLSRv2 uses all parameters and constants defined in [NHDP] and
   additional parameters and constants defined in this document.  All
   but one (RX_HOLD_TIME) destinations
   from all local OLSRv2 interfaces using the Network Topology Graph.
   This calculation MAY use any algorithm, including any means of these additional parameters are router
   parameters as defined in [NHDP].  These proposed values
   choosing between paths of equal length.

   Using the
   additional parameters are appropriate to notation of Section 15.1, initially "backbone" paths using
   only edges X -> Y and W -> U need be constructed (using a minimum
   distance algorithm).  Then paths using only a final edge of the case where all
   parameters (including those defined other
   types may be added.  These MUST NOT replace backbone paths with the
   same destination (and paths terminating in [NHDP]) have an edge Y -> Z SHOULD NOT
   replace paths with any other form of terminating edge).

   Each path will correspond to a single value.
   Proposed values for parameters defined in 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_local_iface_addr := X;

   o  R_next_iface_addr := R;

   o  R_dest_addr := S or Y;

   o  R_dist := 1,

   where R is as defined in Section 15.1 for these types of edges.

   The second type will represent a multiple edge path, which will
   always have first edge of type X -> Y, and will have final edge of
   type W -> U, W -> V, W -> T or Y -> Z. The Routing Tuple will be:

   o  R_local_iface_addr := X;

   o  R_next_iface_addr := Y;

   o  R_dest_addr := U, V, T or Z;

   o  R_dist := the total hop count of the path.

   Finally, Routing Tuples of the second type whose R_dest_addr is not
   routable MAY be discarded.

   An example algorithm for calculating the Routing Set of a router is
   given in Appendix B.

16.  Proposed Values for Parameters and Constants

   This protocol uses all parameters and constants defined in [NHDP] and
   additional parameters and constants defined in this document.  All
   but one (RX_HOLD_TIME) of these additional parameters are router
   parameters as defined in [NHDP].  These proposed values of the
   additional parameters are appropriate to the case where all
   parameters (including those defined in [NHDP]) have a single value.
   Proposed values for parameters defined in [NHDP] are given in that
   document.

17.1.

16.1.  Local History Time Parameters

   o  O_HOLD_TIME := 30 seconds

17.2.

16.2.  Message Interval Parameters

   o  TC_INTERVAL := 5 seconds

   o  TC_MIN_INTERVAL := TC_INTERVAL/4

17.3.

16.3.  Advertised Information Validity Time Parameters

   o  T_HOLD_TIME := 3 x TC_INTERVAL

   o  A_HOLD_TIME := T_HOLD_TIME

17.4.

16.4.  Received Message Validity Time Parameters

   o  RX_HOLD_TIME := 30 seconds

   o  P_HOLD_TIME := 30 seconds

   o  F_HOLD_TIME := 30 seconds

17.5.

16.5.  Jitter Time Parameters

   o  TP_MAXJITTER := HP_MAXJITTER

   o  TT_MAXJITTER := HT_MAXJITTER

   o  F_MAXJITTER := TT_MAXJITTER

17.6.

16.6.  Hop Limit Parameter

   o  TC_HOP_LIMIT := 255

17.7.

16.7.  Willingness Parameter and Constants

   o  WILLINGNESS := WILL_DEFAULT

   o  WILL_NEVER := 0

   o  WILL_DEFAULT := 3

   o  WILL_ALWAYS := 7

18.

17.  Sequence Numbers

   Sequence numbers are used in OLSRv2 with this specification for the purpose of
   discarding "old" information, i.e. messages received out of order.
   However with a limited number of bits for representing sequence
   numbers, wrap-
   around wrap-around (that the sequence number is incremented from
   the maximum possible value to zero) will occur.  To prevent this from
   interfering with the operation of OLSRv2, this protocol, the following MUST
   be observed when determining the ordering of sequence numbers.

   The term MAXVALUE designates in the following one more than the
   largest possible value for a sequence number.  For a 16 bit sequence
   number (as are those defined in this specification) MAXVALUE is
   65536.

   The sequence number S1 is said to be "greater than" the sequence
   number S2 if:

   o  S1 > S2 AND S1 - S2 < MAXVALUE/2 OR

   o  S2 > S1 AND S2 - S1 > MAXVALUE/2

   When sequence numbers S1 and S2 differ by MAXVALUE/2 their ordering
   cannot be determined.  In this case, which should not occur, either
   ordering may be assumed.

   Thus when comparing two messages, it is possible - even in the
   presence of wrap-around - to determine which message contains the
   most recent information.

19.  IANA Considerations

19.1.  Message Types

18.  Extensions

   An extension to this protocol will need to interact with this
   specification, and possibly also with [NHDP].  This specification defines one Message Type, protocol is
   designed to be allocated from permit such interactions, in particular:

   o  Through accessing, and possibly extending, the
   0-223 range of information in the "Message Types" namespace defined
      Information Bases.  All updates to the elements specified in [RFC5444], this
      document are subject to the constraints specified in [NHDP] and
      Appendix D.

   o  Through accessing an outgoing message prior to it being
      transmitted over any OLSRv2 interface, and to add information to
      it as specified in Table 5.

         +------+------+-----------------------------------------+
         | Name | Type | Description                             |
         +------+------+-----------------------------------------+
         |  TC  | TBD1 | Topology Control (MANET-wide signaling) |
         +------+------+-----------------------------------------+

                                  Table 5

19.2.  Message TLV Types [RFC5444].  This specification defines two MAY include Message TLV Types, which must TLVs
      and/or addresses with associated Address Block TLVs.  (Addresses
      without new associated TLVs SHOULD NOT be
   allocated from the "Message TLV Types" namespace defined in
   [RFC5444].  IANA are requested added to make allocations in the 8-127 range
   for these types. messages.)
      This will create two new type extension registries
   with assignments may, for example, be to allow a security protocol, as specified in Table 6 and Table 7.  Specifications
   of these TLVs are
      suggested 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 19, to act as add a |
   |             |      |           | relay TLV containing a cryptographic
      signature to the message.

   o  Through accessing an incoming message, and potentially discarding
      it prior to partake processing by this protocol.  This may, for example,
      allow a security protocol as suggested 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 Section 19 to perform
      verification of message           |
   | CONT_SEQ_NUM | TBD3 | 1 (INCOMPLETE) | Specifies a content        |
   |              |      |                | sequence number for signatures and prevent processing and/or
      forwarding of unverifiable messages by this   |
   |              |      |                | incomplete protocol.

   o  Through accessing an incoming 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 after it has been completely
      processed by this protocol.  This specification defines two Address Block TLV Types, which must be
   allocated from the "Address Block TLV Types" namespace defined may, in
   [RFC5444].  IANA are requested particular, allow a
      protocol which has added information, by way of inclusion of
      appropriate TLVs, or of addresses associated with new TLVs, access
      to make allocations such information after appropriate updates have been recorded
      in the 8-127 range
   for these types.  This will create two new type extension registries
   with assignments as specified Information Bases in Table 8 and Table 9.  Specifications
   of these TLVs are this protocol.

   o  Through requesting that a message be generated at a specific time.
      In that case, message generation MUST still respect the
      constraints in Section 8.1.2 [NHDP] 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 8

   +------------+------+-----------+-----------------------------------+
   |    Name    | Type |    Type   | Description                       |
   |            |      | extension |                                   |
   +------------+------+-----------+-----------------------------------+
   |   GATEWAY  | TBD5 |     0     | Specifies that a given address is |
   |            |      |           | reached via a gateway on the      |
   |            |      |           | originating router                |
   | Unassigned | TBD5 |   1-255   | Expert Review                     |
   +------------+------+-----------+-----------------------------------+

                                  Table 9

   Type extensions indicated as Expert Review SHOULD be allocated as
   described in [RFC5444], based on Expert Review as defined in
   [RFC5226].

   The Address Block TLV with Type = LOCAL_IF defined in [NHDP] is
   extended to also permit inclusion of the Value UNSPEC_IF = 2,
   representing a local address which may or may not be that of the
   interface on which this message is transmitted.

20. 5.4.

19.  Security Considerations

   Currently, OLSRv2 this protocol does not specify any special security
   measures.  As a proactive routing protocol, OLSRv2 makes this protocol is a
   potential target for various attacks.  The various  Various possible
   vulnerabilities are discussed in this section.

20.1.

19.1.  Confidentiality

   Being a proactive protocol, OLSRv2

   This protocol periodically MPR floods topological information to all
   routers in the network.  Hence, if used in an unprotected wireless
   network, the network topology is revealed to anyone who listens to OLSRv2
   the control messages.

   In situations where the confidentiality of the network topology is of
   importance, regular cryptographic techniques, such as exchange of
   OLSRv2 control traffic messages encrypted by PGP [RFC4880] or
   encrypted by some shared secret key, can be applied to ensure that
   control traffic can be read and interpreted by only those authorized
   to do so.

20.2.

19.2.  Integrity

   In OLSRv2, each

   Each router is injecting topological information into the network
   through transmitting HELLO messages and, for some routers, TC
   messages.  If some routers for some reason, malicious or malfunction,
   inject invalid control traffic, network integrity may be compromised.
   Therefore, message authentication is recommended.

   Different such situations may occur, for instance:

   1.  a router generates TC messages, advertising links to non-neighbor
       routers;

   2.  a router generates TC messages, pretending to be another router;

   3.  a router generates HELLO messages, advertising non-neighbor
       routers;

   4.  a router generates HELLO messages, pretending to be another
       router;

   5.  a router forwards altered control messages;

   6.  a router does not forward control messages;

   7.  a router does not select multipoint relays correctly;
   8.  a router forwards broadcast control messages unaltered, but does
       not forward unicast data traffic;

   9.  a router "replays" previously recorded control traffic from
       another router.

   Authentication of the originator router for control messages (for
   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
   countermeasure.  However to prevent routers from repeating old (and
   correctly authenticated) information (situation 9) temporal
   information is required, allowing a router to positively identify
   such delayed messages.

   In general, digital signatures and other required security
   information may be transmitted as a separate OLSRv2 Message Type, or
   signatures and security information may be transmitted within the
   OLSRv2
   HELLO and TC messages, using the TLV mechanism.  Either option
   permits that "secured" and "unsecured" routers can coexist in the
   same network, if desired,

   Specifically, the authenticity of entire OLSRv2 control packets can be
   established through employing IPsec authentication headers, whereas
   authenticity of individual links (situations 1 and 3) require
   additional security information to be distributed.

   An important consideration is that all control messages in OLSRv2 are
   transmitted either to all routers in the neighborhood (HELLO
   messages) or broadcast to all routers in the network (TC messages).

   For example, a control message in OLSRv2 this protocol is always a point-to-
   multipoint transmission.  It is therefore important that the
   authentication mechanism employed permits that any receiving router
   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
   corresponding public key can verify the authenticity of the text.

20.3.

19.3.  Interaction with External Routing Domains

   OLSRv2

   This protocol does, through the use of TC messages, provide a basic
   mechanism for injecting external routing information to the OLSRv2 this
   protocol's domain.  Appendix A also specifies that routing  Routing information can be extracted from the topology table or
   protocol's Information Bases, in particular the routing table Routing Set, of OLSRv2 this
   protocol and, potentially, injected into an external domain domain, if the
   routing protocol governing that domain permits.

   Other than as described in Appendix A, when permits this.

   When operating routers connecting OLSRv2 a MANET using this protocol to an
   external routing domain, care MUST be taken not to allow potentially
   insecure and untrustworthy information to be injected from the OLSRv2 this
   domain to external routing domains.  Care MUST also be taken to
   validate the correctness of information prior to it being injected as
   to avoid polluting routing tables with invalid information.

   A recommended way of extending connectivity from an existing routing
   domain to an OLSRv2 routed a MANET routed using this protocol is to assign an IP
   prefix (under the authority of the routers/gateways connecting the
   MANET with the exiting routing domain) exclusively to that MANET
   area, and to statically configure the gateways to advertise routes
   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 to assign an IP prefix (under the
   authority of the routers/gateways connecting the MANET with the
   exiting routing domain) exclusively to the OLSRv2 MANET area, and to
   configure |
   |            |      |           | reached via a gateway on the gateways statically to advertise routes to that IP
   sequence to routers      |
   |            |      |           | 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 the existing routing domain. [RFC5444], based on Expert Review as defined in
   [RFC5226].

21.  Contributors

   This specification is the result of the joint efforts of the
   following contributors -- listed alphabetically.

   o  Cedric Adjih, INRIA, France, <Cedric.Adjih@inria.fr>

   o  Emmanuel Baccelli, INRIA , France, <Emmanuel.Baccelli@inria.fr>

   o  Thomas Heide Clausen, LIX, France, <T.Clausen@computer.org>
   o  Justin Dean, NRL, USA, <jdean@itd.nrl.navy.mil>

   o  Christopher Dearlove, BAE Systems, UK,
      <chris.dearlove@baesystems.com>

   o  Satoh Hiroki, Hitachi SDL, Japan, <hiroki.satoh.yj@hitachi.com>

   o  Philippe Jacquet, INRIA, France, <Philippe.Jacquet@inria.fr>

   o  Monden Kazuya, Hitachi SDL, Japan, <kazuya.monden.vw@hitachi.com>

   o  Kenichi Mase, Niigata University, Japan, <mase@ie.niigata-u.ac.jp>

   o  Ryuji Wakikawa, KEIO University, Toyota, Japan, <ryuji@sfc.wide.ad.jp>

22.  Acknowledgments

   The authors would like to acknowledge the team behind OLSRv1,
   specified in RFC3626, including Anis Laouiti (INT, Paris), Pascale
   Minet (INRIA, France), Laurent Viennot (INRIA, France), and Amir
   Qayyum (M.A. Jinnah University, Islamabad) for their contributions.

   The authors would like to gratefully acknowledge the following people
   for intense technical discussions, early reviews and comments on the
   specification and its components (listed alphabetically): Khaldoun Al
   Agha (LRI), Teco Boot (Infinity Networks), Song-Yean Cho (LIX), Alan
   Cullen (BAE Systems), Louise Lamont (CRC), Li Li (CRC), Joe Macker
   (NRL), Richard Ogier (SRI), Charles E. Perkins (WiChorus), Shubhranshu Singh (Samsung AIT), Henning
   Rogge (FGAN), and the entire IETF MANET working group.

23.  References

23.1.  Normative References

   [RFC2119]    Bradner, S., "Key words for use in RFCs to Indicate
                Requirement Levels", RFC 2119, BCP 14, March 1997.

   [RFC5148]    Clausen, T., Dearlove, C., and B. Adamson, "Jitter
                considerations in MANETs", RFC 5148, February 2008.

   [RFC5226]    Narten, T. and H. Alvestrand, "Guidelines for Writing an
                IANA Considerations Section in RFCs", RFC 5226, BCP 26,
                May 2008.

   [RFC5444]    Clausen, T., Dean, J., Dearlove, C., and C. Adjih,
                "Generalized MANET Packet/Message Format", RFC 5444,
                February 2009.

   [RFC5497]    Clausen, T. and C. Dearlove, "Representing multi-value
                time in MANETs", RFC 5497, March 2009.

   [RFC5498]    Chakeres, I., "IANA Allocations for MANET Protocols",
                RFC 5498, March 2009.

   [NHDP]       Clausen, T., Dean, J., and C. Dearlove, "MANET
                Neighborhood Discovery Protocol (NHDP)", work in
                progress draft-ietf-manet-nhdp-10.txt, July 2009.

23.2.  Informative References

   [RFC2501]    Macker, J. and S. Corson, "Mobile Ad hoc Networking
                (MANET):  Routing Protocol Performance Issues and
                Evaluation Considerations", RFC 2501, January 1999.

   [RFC3626]    Clausen, T. and P. Jacquet, "The Optimized Link State
                Routing Protocol", RFC 3626, October 2003.

   [RFC4880]    Callas, J., Donnerhacke, L., Finney, H., and R. Thayer,
                "OpenPGP message format", RFC 4880, November 2007.

   [HIPERLAN]   ETSI, "ETSI STC-RES10 Committee. Radio equipment and
                systems: HIPERLAN type 1, functional specifications ETS
                300-652", June 1996.

   [HIPERLAN2]  Jacquet, P., Minet, P., Muhlethaler, P., and N.
                Rivierre, "Increasing reliability in cable free radio
                LANs: Low level forwarding in HIPERLAN.", 1996.

   [MPR]        Qayyum, A., Viennot, L., and A. Laouiti, "Multipoint
                relaying: An efficient technique for flooding in mobile
                wireless networks.", 2001.

   [FSR]        Pei, G., Gerla, M., and T. Chen, "Fisheye state routing
                in mobile ad hoc networks", 2000.

   [FSLS]       Santivanez, C., Ramanathan, R., and I. Stavrakakis,
                "Making link-state routing scale for ad hoc networks",
                2000.

Appendix A.  Router Configuration

   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
   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
   interfaces.  (As noted in Section 14 a router MAY improve on this, by
   coordination between OLSRv2 interfaces.)  A router's MPRs are
   recorded using the element N_mpr in Neighbor Tuples.

   If using this example algorithm then the following steps MUST be
   executed in order for a router to select its MPRs:

   1.  Set N_mpr := false in all Neighbor Tuples;

   2.  For each Neighbor Tuple with N_symmetric = true and N_willingness
       = WILL_ALWAYS, set N_mpr := true;

   3.  For each OLSRv2 interface of the router, use the algorithm in
       Appendix B.2. A.2.  Note that this sets N_mpr := true for some
       Neighbor Tuples, these routers are already selected as MPRs when
       using the algorithm for following OLSRv2 interfaces.

   4.  OPTIONALLY, consider each selected MPR in turn, and if the set of
       selected MPRs without that router still satisfies the necessary
       conditions, for all OLSRv2 interfaces, then that router MAY be
       removed from the set of MPRs.  This process MAY be repeated until
       no MPRs are removed.  Routers MAY be considered in order of
       increasing N_willingness.

   Note that only symmetric strict 2-hop neighbors are considered, thus:

   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, as MUST be symmetric 2-hop neighbor routers which are
      algorithm (and hence also
   symmetric 1-hop neighbor routers (i.e. when considering 2-Hop Tuples, ignore any 2-Hop Tuples whose N2_2hop_addr
      N2_neighbor_iface_addr_list is included in the
      N_neighbor_addr_list of any such Neighbor Tuple, or 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_neighbor_iface_addr_list N2_2hop_addr is included in the
      N_neighbor_addr_list of any Neighbor Tuple with N_willingness = WILL_NEVER).

B.1. Tuple).

A.1.  Terminology

   The following terminology will be used when selecting MPRs for the
   OLSRv2 interface I:

   N(I)  - The set of symmetric 1-hop neighbors which have a symmetric
      link to I.

   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
      considering only information received over I (in which case N2(I)
      is the set of N2_2hop_addr in 2-Hop Tuples in the 2-Hop Set for
      OLSRv2 interface I).

   Connected to I via Y  - An address A in N2(I) is connected to I via a
      router Y in N(I) if A is an address of an interface of a symmetric
      1-hop neighbor of Y (i.e.  A is the N2_2hop_addr in a 2-Hop Tuple
      in the 2-Hop Set for OLSRv2 interface I, and whose
      N2_neighbor_iface_addr_list is contained in the set of interface
      addresses of Y).

   D(Y, I)  - For a router Y in N(I), the number of addresses in N2(I)
      which are connected to I via Y.

   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
      router which has already been selected as an MPR.

B.2.

A.2.  MPR Selection Algorithm for each OLSRv2 Interface

   When selecting MPRs for the OLSRv2 interface I:

   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
       as an MPR (i.e. set N_mpr := true in the Neighbor Tuple
       corresponding to Y).

   2.  While there exists any router Y in N(I) with R(Y, I) > 0:

       1.  Select a router Y in N(I) with R(Y, I) > 0 in the following
           order of priority:

           +  greatest N_willingness in the Neighbor Tuple corresponding
              to Y, THEN;

           +  greatest R(Y, I), THEN;

           +  greatest D(Y, I), THEN;

           +  N_mpr_selector is equal to true, if possible, THEN;

           +  any choice.

       2.  Select Y as an MPR (i.e. set N_mpr := true in the Neighbor
           Tuple corresponding to Y).

Appendix C. B.  Example Algorithm for Calculating the Routing Set

   The following procedure is given as an example for calculating the
   Routing Set using a variation of Dijkstra's algorithm.  First all
   Routing Tuples are removed, and then then, using the selections and
   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

B.1.  Local Symmetric Links Interfaces and Neighbors

   The following selections and definitions are made:

   1.  For each Local Interface Tuple:

       1.  Select Tuple, select an address (the "local address") in
           I_local_iface_addr_list. from its
       I_local_iface_addr_list, this is defined as the selected address
       for this Local Interface Tuple.

   2.  For each Link Tuple, the selected address of its corresponding
       Local Interface Tuple is defined as the selected local address
       for this local interface Local Interface Tuple.

   3.  For each Neighbor Tuple with L_status N_symmetric =
           SYMMETRIC:

           1. true, the selected
       local address is defined as the selected local address of the
       selected Link Tuple for that Neighbor Tuple.

   4.  For each address (the "current address") (N_orig_addr or in
               L_neighbor_iface_addr_list, if there is no Routing N_neighbor_addr_list, the
       "neighbor address") from a Neighbor Tuple with R_dest_addr N_symmetric = current address, then add
       true, select a Routing Link Tuple with:

               -  R_dest_addr := current address;

               -  R_next_iface_addr := current address;

               -  R_dist := 1;

               -  R_local_iface_addr := local 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.

   2.  This is defined as the selected Link Tuple for that
       neighbor address.

   5.  For each address (N_orig_addr or in N_neighbor_addr_list, the
       "neighbor address") from a Neighbor Tuple whose N_neighbor_addr_list contains with N_symmetric =
       true, a selected address from the
       R_dest_addr L_neighbor_iface_addr_list of a
       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.

   6.  Routing Tuple (the "previous Tuple"): preference is decided by preference for
       corresponding Neighbor Tuples in this order:

       *  For greater N_willingness.

       *  For N_mpr_selector = true over N_mpr_selector = false.

B.2.  Add Neighbor Routers

   The following procedure is executed once.

   1.  For each address (the "current address") in
           N_neighbor_addr_list, if there is no Routing Neighbor Tuple with
           R_dest_addr N_symmetric = current address, then true, add a Routing
       Tuple with:

           +

       *  R_dest_addr := current address;

           + N_orig_addr;

       *  R_next_iface_addr := R_dest_addr of the previous Tuple;

           +  R_dist := 1;

           + selected link address;

       *  R_local_iface_addr := R_local_iface_addr of the previous
              Tuple.

C.2. selected local address;

       *  R_dist := 1.

B.3.  Add Remote Symmetric Links Routers

   The following procedure, which adds Routing Tuples for destination
   routers h+1 hops away, MUST be procedure is executed for each value of h, starting
   with h := 1 and incrementing by 1 for each iteration.  The execution
   MUST stop if no new Routing Tuples are added in an iteration.

   1.  For each Router Topology Tuple, if:

       *  T_dest_addr  TR_to_orig_addr is not equal to the R_dest_addr of any Routing Tuple,
          AND;

       *  for the Advertising Remote Router
          Tuple with AR_orig_addr =
          T_orig_addr, there is an address added in the AR_addr_list which an earlier stage, AND;

       *  TR_from_orig_addr is equal to the R_dest_addr of a Routing
          Tuple (the "previous
          Routing Tuple") whose with R_dist = h (the "previous Routing Tuple"),

       then add a new Routing Tuple, with:

       *  R_dest_addr := T_dest_addr; TR_to_orig_addr;

       *  R_next_iface_addr := R_next_iface_addr of the previous Routing
          Tuple;

       *  R_dist := h+1;

       *  R_local_iface_addr := R_local_iface_addr of the previous
          Routing Tuple.

       More Tuple;

       *  R_dist := h+1.

       There may be more than one Topology possible Routing Tuple that may be usable to select the next hop
       R_next_iface_addr
       added for reaching the address R_dest_addr.  Ties
       should be broken an R_dest_addr in this stage.  If so, then, for each
       such that routers with greater willingness are
       preferred, and between routers of equal willingness, MPR
       selectors are R_dest_addr, a Routing Tuple which is preferred over non-MPR selectors.

   2.  After the above iteration has completed, if h = 1, for SHOULD be
       added.

B.4.  Add Neighbor Addresses

   The following procedure is executed once.

   1.  For each 2-Hop Neighbor Tuple where: with N_symmetric = true:

       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:

       *  N2_2hop_addr  TA_dest_addr is not equal to the R_dest_addr of any Routing Tuple,
          Tuple added in an earlier stage, AND;

       *  The Neighbor Tuple whose N_neighbor_addr_list contains
          N2_neighbor_iface_addr_list has N_willingness not  TR_from_orig_addr is equal to
          WILL_NEVER

       select the R_dest_addr of a Routing
          Tuple (the "previous Routing Tuple") whose
       R_dest_addr is contained in N2_neighbor_iface_addr_list, and Tuple"),

       then add a new Routing Tuple Tuple, with:

       *  R_dest_addr := N2_2hop_addr; TA_dest_addr;

       *  R_next_iface_addr := R_next_iface_addr of the previous Routing
          Tuple;

       *  R_dist := 2;

       *  R_local_iface_addr := R_local_iface_addr of the previous
          Routing Tuple.

       More Tuple;

       *  R_dist := R_dist of the previous Routing Tuple + 1.

       There may be more than one 2-Hop Neighbor possible Routing Tuple that may be usable to select the
       next hop R_next_iface_addr
       added for reaching the address R_dest_addr.
       Ties should be broken an R_dest_addr in this stage.  If so, then, for each
       such that routers with greater willingness
       are preferred, and between routers of equal willingness, MPR
       selectors are R_dest_addr, a Routing Tuple which is preferred over non-MPR selectors.

C.3. SHOULD be
       added.

B.6.  Add Attached Networks

   The following procedure is executed once.

   1.  For each Attached Network Tuple, if for if:

       *  AN_orig_addr is not equal to the Advertising Remote
       Router R_dest_addr of any Routing
          Tuple with AR_orig_addr = AN_orig_addr, there is an
       address added in the AR_addr_list which an earlier stage, AND;

       *  AN_orig_addr 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, Tuple),

       then add a new Routing Tuple Tuple, with:

           +

       *  R_dest_addr := AN_net_addr;

           +

       *  R_next_iface_addr := R_next_iface_addr of the previous Routing
          Tuple;

           +  R_dist

       *  R_local_iface_addr := (R_dist R_local_iface_addr of the previous
          Routing Tuple) +
              AN_dist;

           +  R_local_iface_addr Tuple;

       *  R_dist := R_local_iface_addr R_dist of the previous Routing Tuple.

       2.  Otherwise if Tuple + AN_dist.

       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.

B.7.  Add 2-Hop Neighbors

   The following procedure is executed once.

   1.  For each 2-Hop Tuple, if:

       *  N2_2hop_addr is a routable address, AND;

       *  N2_2hop_addr is not equal to the R_dest_addr of any Routing
          Tuple added in an earlier stage,

       then define the "previous Routing Tuple" as that with R_dest_addr
       = AN_net_addr
           (the "current Routing Tuple") has R_dist > (R_dist N_orig_addr of the
           previous Routing Tuple) + AN_dist, then modify the current corresponding Neighbor Tuple, and add a new
       Routing Tuple by:

           + Tuple, with:

       *  R_dest_addr := N2_2hop_addr;

       *  R_next_iface_addr := R_next_iface_addr of the previous Routing
          Tuple;

           +  R_dist := (R_dist of the previous Routing Tuple) +
              AN_dist;

           +

       *  R_local_iface_addr := R_local_iface_addr of the previous
          Routing Tuple. Tuple;

       *  R_dist := 2.

       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 D. C.  Example Message Layout

   An example TC message is as follows.  The message has full 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
   have length four octets, here being IPv4 addresses.  The overall
   message length is 65 57 octets.

   The message has a Message TLV Block with content length 13 octets
   containing three TLVs.  The first two TLVs are interval and validity
   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
   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
   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
   of 2 octets.

   The message has two Address Blocks.  (This is not necessary, the
   information could be conveyed using a single Address Block, the use
   of two Address Blocks, which is also allowed, is illustrative only.)
   The first Address Block contains
   6 3 addresses, with Flags octet value
   128, hence with a Head section, (with length 2 octets) but no Tail
   section, and hence Mid sections with length two octets.  The
   following TLV Block (content length 6 octets) contains a single LOCAL_IF
   NBR_ADDR_TYPE TLV (Flags octet value 48) 16, includes a Value but no
   indexes) indicating that the first three these addresses (indexes 0 to 2) are associated with the
   Value (with Value Length 1 octet) UNSPEC_IF, ROUTABLE_ORIG, i.e. they are the originating router's local addresses.  The remaining
   three addresses have no associated TLV, they are the
   originator addresses of advertised neighbors. neighbors that are also routable
   addresses.

   The second Address Block contains 1 address, with Flags octet 176
   indicating that there is a Head section (with length 2 octets), that
   the Tail section (length 2 octets) consists of zero valued octets
   (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
   Block (content length 8 octets) includes one TLV that indicates that
   the originating router is a gateway to this network, at a given
   number of hops distance (Value Length 1 octet).  The TLV Flags octet
   value of 16 again indicates that a Value, but no indexes are needed.

      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
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |      TC       |1 1 1 1 0 0 1 1|0 0 0 0 0 0 0 0 0 1 0 0 0 1 1 1 0 0 1|
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |                      Originator Address                       |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |   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 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 1 0|         Value (ANSN)          |0 0 0 0 0 0 1 1 0| 1|
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |1 0 0 0 0 0 0 0|0 0 0 0 0 0 1 0|             Head              |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |              Mid              |              Mid              |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |              Mid              |              Mid              |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |              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|
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     | NBR_ADDR_TYPE |0 0 0 1 0 0 0 0 0|0 0 0 0 0 0 1 0|0 0 0 0 0 0 0 1|   UNSPEC_IF 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      |
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |  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|
     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
     |  Number Hops  |
     +-+-+-+-+-+-+-+-+

Appendix E. D.  Constraints

   Any process which updates the Local Information Base, the
   Neighborhood Information Base or the Topology Information Base MUST
   ensure that all constraints specified in this appendix are
   maintained, as well as those specified in [NHDP].

   In each Originator Tuple:

   o  O_orig_addr MUST NOT equal any other O_orig_addr.

   o  O_orig_addr MUST NOT equal this router's originator address.

   In each Local Attached Network Tuple:

   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
      Local Interface Tuple or be equal to the IR_local_iface_addr of any
      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.

   In each Link Tuple:

   o  L_neighbor_iface_addr_list MUST NOT contain the AL_net_addr of any
      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

   In each address Neighbor Tuple:

   o  N_orig_addr MUST NOT be changed to unknown.

   o  N_orig_addr MUST NOT equal this router's originator address, or
      equal O_orig_addr in this
      L_neighbor_iface_addr_list, there any Originator Tuple.

   o  N_orig_addr MUST be an NOT equal
      RY_neighbor_iface_addr in the Relay Set associated with the same
      OLSRv2 interface.

   In each Neighbor Tuple: 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 of 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
      WILL_ALWAYS, inclusive.

   o  If N_mpr = true, then N_symmetric MUST be true and N_willingness
      MUST NOT equal WILL_NEVER.

   o  If N_symmetric = true and N_mpr = false, then N_willingness MUST
      NOT equal WILL_ALWAYS.

   o  If N_mpr_selector = true, then N_symmetric MUST be true and
      N_advertised MUST be true.

   o  If N_mpr_selector N_advertised = true, then, for each address in this
      N_neighbor_addr_list, there then N_symmetric MUST be an equal A_neighbor_addr in
      the Advertised Neighbor Set. true.

   In each Lost Neighbor Tuple:

   o  NL_neighbor_addr MUST NOT equal the AL_net_addr of any Local
      Attached Network Tuple.

   In each 2-Hop Tuple:

   o  N2_2hop_addr MUST NOT equal the AL_net_addr of any Local Attached
      Network Tuple.

   In each Received Tuple:

   o  RX_orig_addr MUST NOT equal this router's originator address or
      any O_orig_addr.

   o  Each ordered triple (RX_type, RX_orig_addr, RX_seq_number) MUST
      NOT address,
      equal the corresponding triple O_orig_addr in any other Received Tuple in
      the same Received Set.

   In each Processed Tuple:

   o  P_orig_addr MUST NOT equal this router's originator address Originator Tuple, or any
      O_orig_addr.

   o  Each ordered triple (P_type, P_orig_addr, P_seq_number) MUST NOT equal the corresponding triple
      AL_net_addr in any other Processed Local Attached Network Tuple.

   In each Forwarded 2-Hop Tuple:

   o  F_orig_addr  N2_2hop_addr MUST NOT equal this router's originator address or any
      O_orig_addr.

   o  Each ordered triple (F_type, F_orig_addr, F_seq_number) MUST NOT address,
      equal the corresponding triple O_orig_addr in any other Forwarded Tuple.

   In each Relay Tuple:

   o  RY_neighbor_iface_addr MUST NOT Originator Tuple, or equal the RY_neighbor_iface_addr
      in any other Relay Tuple in the same Relay Set.

   o  RY_neighbor_iface_addr MUST be
      AL_net_addr in the L_neighbor_iface_addr_list
      of a Link Tuple with L_status = SYMMETRIC.

   In the Advertised Neighbor Set:

   o  Each A_neighbor_addr MUST NOT equal any other A_neighbor_addr.

   o  Each A_neighbor_addr MUST be in the N_neighbor_addr_list of a
      Neighbor Tuple with N_symmetric = true. Local Attached Network Tuple.

   In each Advertising Remote Router Tuple:

   o  AR_orig_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
      equal the O_orig_addr in any O_orig_addr. Originator Tuple.

   o  AR_orig_addr MUST NOT equal the AR_orig_addr AL_net_addr in any other ANSN
      History Local Attached
      Network Tuple.

   o  AR_addr_list  AR_orig_addr MUST NOT be empty. equal the AR_orig_addr in any other
      Advertising Remote Router Tuple.

   In each Router Topology Tuple:

   o  AR_addr_list  There MUST NOT contain any duplicated addresses. be an Advertising Remote Router Tuple with AR_orig_addr
      = TR_from_orig_addr.

   o  AR_addr_list  TR_to_orig_addr MUST NOT contain any address which is be in the I_local_iface_addr_list of in any
      Local Interface Tuple or be equal
      to the IR_local_iface_addr of in any
      Removed Interface Address Tuple.

   o  AR_addr_list  TR_to_orig_addr MUST NOT contain any equal this router's originator address which is or
      equal the O_orig_addr in any Originator Tuple.

   o  TR_to_orig_addr MUST NOT equal the AL_net_addr
      of in any Local
      Attached Network Tuple.

   o  The ordered pair (TR_from_orig_addr, TR_to_orig_addr) MUST NOT
      equal the corresponding pair for any other Router Topology Tuple.

   o  TR_seq_number MUST NOT be greater than AR_seq_number in the
      Advertising Remote Router Tuple with AR_orig_addr =
      TR_from_orig_addr.

   In each Routable Address Topology Tuple:

   o  T_dest_addr  There MUST be an Advertising Remote Router Tuple with AR_orig_addr
      = TA_from_orig_addr.

   o  TA_dest_addr MUST be routable.

   o  TA_dest_addr MUST NOT be in the I_local_iface_addr_list of in any
      Local Interface Tuple or be equal to the IR_local_iface_addr of in any
      Removed Interface Address Tuple.

   o  T_dest_addr  TA_dest_addr MUST NOT equal this router's originator address or
      equal the O_orig_addr in any Originator Tuple.

   o  TA_dest_addr MUST NOT equal the AL_net_addr of in any Local Attached
      Network Tuple.

   o  There  The ordered pair (TA_from_orig_addr, TA_dest_addr) MUST be an Advertising Remote Router Tuple with AR_orig_addr
      = T_orig_addr. NOT equal
      the corresponding pair for any other Attached Network Tuple.

   o  T_dest_addr  TA_seq_number MUST NOT be greater than AR_seq_number in the AR_addr_list of the
      Advertising Remote Router Tuple with AR_orig_addr = T_orig_addr.
      TA_from_orig_addr.

   In each Attached Network Tuple:

   o  T_seq_number  There MUST NOT be greater than AR_seq_number of the an 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
      corresponding pair in any other Topology Tuple.

   In each Attached Network Tuple: AN_orig_addr.

   o  AN_net_addr MUST NOT be in the I_local_iface_addr_list of in any
      Local Interface Tuple or be equal to the IR_local_iface_addr of IR_local_iface_addr in any
      Removed Interface Address Tuple.

   o  AN_net_addr MUST NOT equal this router's originator address or
      equal the O_orig_addr in any Removed Interface Address Originator Tuple.

   o  AN_net_addr MUST NOT equal the AL_net_addr of in any Local Attached
      Network Tuple.

   o  There  The ordered pair (AN_orig_addr, AN_net_addr) MUST be an Advertising Remote Router Tuple with AR_orig_addr
      = AN_orig_addr. NOT equal the
      corresponding pair for any other Attached Network Tuple.

   o  AN_seq_number MUST NOT be greater than AR_seq_number of in the
      Advertising Remote Router Tuple with AR_orig_addr = AN_orig_addr.

   o  AN_dist MUST NOT be less than zero.

   In each Received Tuple:

   o  The  RX_orig_addr MUST NOT equal this router's originator address or
      the O_orig_addr in any Originator Tuple.

   o  Each ordered pair (AN_net_addr, AN_orig_addr) triple (RX_type, RX_orig_addr, RX_seq_number) MUST
      NOT equal the corresponding pair triple for any other Received Tuple in
      the same Received Set.

   In each Processed Tuple:

   o  P_orig_addr MUST NOT equal this router's originator address or
      equal the O_orig_addr in any Originator Tuple.

   o  Each ordered triple (P_type, P_orig_addr, P_seq_number) MUST NOT
      equal the corresponding triple for any other Attached Network Processed Tuple.

   In each Forwarded Tuple:

   o  F_orig_addr MUST NOT equal this router's originator address or
      equal the O_orig_addr in any Originator Tuple.

   o  Each ordered triple (F_type, F_orig_addr, F_seq_number) MUST NOT
      equal the corresponding triple for any other Forwarded Tuple.

Appendix F. E.  Flow and Congestion Control

   Due to its proactive nature, the OLSRv2 this protocol has a natural control over
   the flow of its control traffic.  Routers transmit control messages
   at predetermined rates specified and bounded by message intervals.

   OLSRv2

   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.  OLSRv2
   local
   Local signaling, therefore, shares the characteristics and
   constraints of [NHDP].

   Furthermore, MPR flooding the use of MPRs can greatly reduces reduce the signaling
   overhead from
   from link state information dissemination in two ways. ways,
   attaining both flooding reduction and topology reduction.  First,
   using MPR flooding, the cost of distributing link state information
   throughout the network is reduced, as compared to when using classic
   flooding, since only MPRs need to forward link state declaration
   messages.  Second, the amount of link state information for a router
   to declare is reduced to need only contain that router's MPR
   selectors.  This reduces the size of a link state declaration as
   compared to declaring full link state information.  In particular
   some routers may not need to declare any such information.  Second, using MPR flooding, the cost of
   distributing link state information throughout the network is greatly
   reduced, as compared to when using classic flooding, since only MPRs
   need to forward link state declaration messages.  In dense
   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
   data traffic and pushes further the frontier of congestion.

   Since the control traffic is continuous and periodic, it keeps the
   quality of the links used in routing more stable.  However, using
   certain OLSRv2
   some options, some control messages (HELLO messages or TC messages)
   may be intentionally sent in advance of their deadline in order to
   increase the responsiveness of the protocol to topology changes.
   This may cause a small, temporary, and local increase of control
   traffic, however this is at all times bounded by the use of minimum
   message intervals.

Authors' Addresses

   Thomas Heide Clausen
   LIX, Ecole Polytechnique

   Phone: +33 6 6058 9349
   EMail: T.Clausen@computer.org
   URI:   http://www.ThomasClausen.org/

   Christopher Dearlove
   BAE Systems ATC

   Phone: +44 1245 242194
   EMail: chris.dearlove@baesystems.com
   URI:   http://www.baesystems.com/

   Philippe Jacquet
   Project Hipercom, INRIA

   Phone: +33 1 3963 5263
   EMail: philippe.jacquet@inria.fr

   The OLSRv2 Design Team
   MANET Working Group