draft-ietf-idr-bgp-ls-segment-routing-msd-02.txt   draft-ietf-idr-bgp-ls-segment-routing-msd-03.txt 
IDR Working Group J. Tantsura IDR Working Group J. Tantsura
Internet-Draft Nuage Networks Internet-Draft Apstra, Inc.
Intended status: Standards Track U. Chunduri Intended status: Standards Track U. Chunduri
Expires: February 14, 2019 Huawei USA Expires: August 23, 2019 Huawei USA
G. Mirsky G. Mirsky
ZTE Corp. ZTE Corp.
S. Sivabalan S. Sivabalan
Cisco Cisco
August 13, 2018 N. Triantafillis
Apstra, Inc.
February 19, 2019
Signaling MSD (Maximum SID Depth) using Border Gateway Protocol Link- Signaling MSD (Maximum SID Depth) using Border Gateway Protocol Link-
State State
draft-ietf-idr-bgp-ls-segment-routing-msd-02 draft-ietf-idr-bgp-ls-segment-routing-msd-03
Abstract Abstract
This document defines a way for a Border Gateway Protocol Link-State This document defines a way for a Border Gateway Protocol Link-State
(BGP-LS) speaker to advertise multiple types of supported Maximum SID (BGP-LS) speaker to advertise multiple types of supported Maximum SID
Depths (MSDs) at node and/or link granularity. Depths (MSDs) at node and/or link granularity.
Such advertisements allow logically centralized entities (e.g., Such advertisements allow logically centralized entities (e.g.,
centralized controllers) to determine whether a particular SID stack centralized controllers) to determine whether a particular SID stack
can be supported in a given network. can be supported in a given network.
skipping to change at page 1, line 42 skipping to change at page 1, line 44
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on February 14, 2019. This Internet-Draft will expire on August 23, 2019.
Copyright Notice Copyright Notice
Copyright (c) 2018 IETF Trust and the persons identified as the Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
Internet-DrafSignaling MSD (Maximum SID Depth) using BGP-LS August 2018
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of (https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Conventions used in this document . . . . . . . . . . . . 3 1.1. Conventions used in this document . . . . . . . . . . . . 3
1.1.1. Terminology . . . . . . . . . . . . . . . . . . . . . 3 1.1.1. Terminology . . . . . . . . . . . . . . . . . . . . . 3
1.1.2. Requirements Language . . . . . . . . . . . . . . . . 3 1.1.2. Requirements Language . . . . . . . . . . . . . . . . 3
2. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 3 2. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 3
3. MSD supported by a node . . . . . . . . . . . . . . . . . . . 3 3. MSD supported by a node . . . . . . . . . . . . . . . . . . . 4
4. MSD supported on a link . . . . . . . . . . . . . . . . . . . 4 4. MSD supported on a link . . . . . . . . . . . . . . . . . . . 4
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5
6. Security Considerations . . . . . . . . . . . . . . . . . . . 5 6. Security Considerations . . . . . . . . . . . . . . . . . . . 5
7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 5 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 5
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 5
8.1. Normative References . . . . . . . . . . . . . . . . . . 5 8.1. Normative References . . . . . . . . . . . . . . . . . . 5
8.2. Informative References . . . . . . . . . . . . . . . . . 6 8.2. Informative References . . . . . . . . . . . . . . . . . 6
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 7
1. Introduction 1. Introduction
skipping to change at page 3, line 4 skipping to change at page 3, line 9
in SR PCE Capability TLV and METRIC Object. However, if PCEP is not in SR PCE Capability TLV and METRIC Object. However, if PCEP is not
supported/configured on the head-end of a SR tunnel or a Binding-SID supported/configured on the head-end of a SR tunnel or a Binding-SID
anchor node and controller does not participate in IGP routing, it anchor node and controller does not participate in IGP routing, it
has no way to learn the MSD of nodes and links which has been has no way to learn the MSD of nodes and links which has been
configured. BGP-LS [RFC7752] defines a way to expose topology and configured. BGP-LS [RFC7752] defines a way to expose topology and
associated attributes and capabilities of the nodes in that topology associated attributes and capabilities of the nodes in that topology
to a centralized controller. to a centralized controller.
Other types of MSD are known to be useful. For example, Other types of MSD are known to be useful. For example,
[I-D.ietf-ospf-mpls-elc] and [I-D.ietf-isis-mpls-elc] define Readable [I-D.ietf-ospf-mpls-elc] and [I-D.ietf-isis-mpls-elc] define Readable
Internet-DrafSignaling MSD (Maximum SID Depth) using BGP-LS August 2018
Label Depth Capability (RLDC) that is used by a head-end to insert an Label Depth Capability (RLDC) that is used by a head-end to insert an
Entropy Label (EL) at a depth that can be read by transit nodes. Entropy Label (EL) at a depth that can be read by transit nodes.
1.1. Conventions used in this document 1.1. Conventions used in this document
1.1.1. Terminology 1.1.1. Terminology
BGP-LS: Distribution of Link-State and TE Information using Border BGP-LS: Distribution of Link-State and TE Information using Border
Gateway Protocol Gateway Protocol
skipping to change at page 3, line 45 skipping to change at page 3, line 47
capitals, as shown here . capitals, as shown here .
2. Problem Statement 2. Problem Statement
In existing technology only PCEP has extension to signal the MSD (SR In existing technology only PCEP has extension to signal the MSD (SR
PCE Capability TLV/ METRIC Object as defined in PCE Capability TLV/ METRIC Object as defined in
[I-D.ietf-pce-segment-routing],If PCEP is not supported by the node [I-D.ietf-pce-segment-routing],If PCEP is not supported by the node
(head-end of the SR tunnel) controller has no way to learn the MSD of (head-end of the SR tunnel) controller has no way to learn the MSD of
the node/link configured. OSPF and IS-IS extensions are defined in: the node/link configured. OSPF and IS-IS extensions are defined in:
[I-D.ietf-ospf-segment-routing-msd] [RFC8476]
[I-D.ietf-isis-segment-routing-msd] [RFC8491]
3. MSD supported by a node 3. MSD supported by a node
Node MSD is encoded in a new Node Attribute TLV, as defined in Node MSD is encoded in a new Node Attribute TLV, as defined in
[RFC7752] [RFC7752]
Internet-DrafSignaling MSD (Maximum SID Depth) using BGP-LS August 2018
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | | Type | Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Sub-Type and Value ... | Sub-Type and Value ...
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ...
Figure 1: Node attribute format Figure 1: Node attribute format
Type : A 2-octet field specifying code-point of the new TLV type. Type : A 2-octet field specifying code-point of the new TLV type.
Code-point:(TBD1) from BGP-LS Node Descriptor, Link Descriptor, Code-point:(TBD1) from BGP-LS Node Descriptor, Link Descriptor,
Prefix Descriptor, and Attribute TLVs registry Prefix Descriptor, and Attribute TLVs registry
Length: A 2-octet field that indicates the length of the value Length: A 2-octet field that indicates the length of the value
portion portion
Sub-Type and value fields are as defined in corresponding OSPF Sub-Type and value fields are as defined in corresponding OSPF
[I-D.ietf-ospf-segment-routing-msd] and IS-IS [RFC8476] and IS-IS [RFC8491] extensions.
[I-D.ietf-isis-segment-routing-msd] extensions.
4. MSD supported on a link 4. MSD supported on a link
Link MSD is encoded in a New Link Attribute TLV, as defined in Link MSD is encoded in a New Link Attribute TLV, as defined in
[RFC7752] [RFC7752]
0 1 2 3 0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Type | Length | | Type | Length |
skipping to change at page 4, line 49 skipping to change at page 5, line 4
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ...
Figure 2: Link attribute format Figure 2: Link attribute format
Type : A 2-octet field specifying code-point of the new TLV type. Type : A 2-octet field specifying code-point of the new TLV type.
Code-point:(TBD2) from BGP-LS Node Descriptor, Link Descriptor, Code-point:(TBD2) from BGP-LS Node Descriptor, Link Descriptor,
Prefix Descriptor, and Attribute TLVs registry Prefix Descriptor, and Attribute TLVs registry
Length: A 2-octet field that indicates the length of the value Length: A 2-octet field that indicates the length of the value
portion portion
Sub-Type and value fields are as defined in corresponding OSPF Sub-Type and value fields are as defined in corresponding OSPF
[I-D.ietf-ospf-segment-routing-msd] and IS-IS [RFC8476] and IS-IS [RFC8491] extensions.
[I-D.ietf-isis-segment-routing-msd] extensions.
Internet-DrafSignaling MSD (Maximum SID Depth) using BGP-LS August 2018
5. IANA Considerations 5. IANA Considerations
We request IANA assign code points from the registry BGP-LS Node We request IANA assign code points from the registry BGP-LS Node
Descriptor, Link Descriptor, Prefix Descriptor, and Attribute TLVs, Descriptor, Link Descriptor, Prefix Descriptor, and Attribute TLVs,
as follows: TLV Code Point Description IS-IS TLV/Sub-TLV Reference as follows: TLV Code Point Description IS-IS TLV/Sub-TLV Reference
TBD1 Node MSD 242/23 (this document) TBD2 Link MSD TBD1 Node MSD 242/23 (this document) TBD2 Link MSD
(22,23,25,141,222,223)/15 (this document) (22,23,25,141,222,223)/15 (this document)
6. Security Considerations 6. Security Considerations
Advertisement of the additional information defined in this document Advertisement of the additional information defined in this document
that is false, e.g., an MSD that is incorrect, may result in a path that is false, e.g., an MSD that is incorrect, may result in a path
computation failing, having a service unavailable, or instantiation computation failing, having a service unavailable, or instantiation
of a path that can't be supported by the head-end (the node of a path that can't be supported by the head-end (the node
performing the imposition). performing the imposition).
This document does not introduce security issues beyond those This document does not introduce security issues beyond those
discussed in [RFC7752], [I-D.ietf-ospf-segment-routing-msd] and discussed in [RFC7752], [RFC8476] and [RFC8491] extensions.
[I-D.ietf-isis-segment-routing-msd]
7. Acknowledgements 7. Acknowledgements
We like to thank Nikos Triantafillis, Acee Lindem, Ketan Talaulikar, We like to thank Acee Lindem, Ketan Talaulikar, Stephane Litkowski
Stephane Litkowski and Bruno Decraene for their reviews and valuable and Bruno Decraene for their reviews and valuable comments.
comments.
8. References 8. References
8.1. Normative References 8.1. Normative References
[I-D.ietf-isis-segment-routing-msd]
Tantsura, J., Chunduri, U., Aldrin, S., and L. Ginsberg,
"Signaling MSD (Maximum SID Depth) using IS-IS", draft-
ietf-isis-segment-routing-msd-13 (work in progress), July
2018.
[I-D.ietf-ospf-segment-routing-msd]
Tantsura, J., Chunduri, U., Aldrin, S., and P. Psenak,
"Signaling MSD (Maximum SID Depth) using OSPF", draft-
ietf-ospf-segment-routing-msd-15 (work in progress), July
2018.
[I-D.ietf-pce-segment-routing] [I-D.ietf-pce-segment-routing]
Sivabalan, S., Filsfils, C., Tantsura, J., Henderickx, W., Sivabalan, S., Filsfils, C., Tantsura, J., Henderickx, W.,
and J. Hardwick, "PCEP Extensions for Segment Routing", and J. Hardwick, "PCEP Extensions for Segment Routing",
draft-ietf-pce-segment-routing-12 (work in progress), June draft-ietf-pce-segment-routing-15 (work in progress),
2018. February 2019.
Internet-DrafSignaling MSD (Maximum SID Depth) using BGP-LS August 2018
[I-D.ietf-spring-segment-routing-mpls]
Bashandy, A., Filsfils, C., Previdi, S., Decraene, B.,
Litkowski, S., and R. Shakir, "Segment Routing with MPLS
data plane", draft-ietf-spring-segment-routing-mpls-14
(work in progress), June 2018.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and [RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and
S. Ray, "North-Bound Distribution of Link-State and S. Ray, "North-Bound Distribution of Link-State and
Traffic Engineering (TE) Information Using BGP", RFC 7752, Traffic Engineering (TE) Information Using BGP", RFC 7752,
DOI 10.17487/RFC7752, March 2016, DOI 10.17487/RFC7752, March 2016,
<https://www.rfc-editor.org/info/rfc7752>. <https://www.rfc-editor.org/info/rfc7752>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>. May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8476] Tantsura, J., Chunduri, U., Aldrin, S., and P. Psenak,
"Signaling Maximum SID Depth (MSD) Using OSPF", RFC 8476,
DOI 10.17487/RFC8476, December 2018,
<https://www.rfc-editor.org/info/rfc8476>.
[RFC8491] Tantsura, J., Chunduri, U., Aldrin, S., and L. Ginsberg,
"Signaling Maximum SID Depth (MSD) Using IS-IS", RFC 8491,
DOI 10.17487/RFC8491, November 2018,
<https://www.rfc-editor.org/info/rfc8491>.
8.2. Informative References 8.2. Informative References
[I-D.ietf-isis-mpls-elc] [I-D.ietf-isis-mpls-elc]
Xu, X., Kini, S., Sivabalan, S., Filsfils, C., and S. Xu, X., Kini, S., Sivabalan, S., Filsfils, C., and S.
Litkowski, "Signaling Entropy Label Capability and Entropy Litkowski, "Signaling Entropy Label Capability and Entropy
Readable Label Depth Using IS-IS", draft-ietf-isis-mpls- Readable Label Depth Using IS-IS", draft-ietf-isis-mpls-
elc-05 (work in progress), July 2018. elc-06 (work in progress), September 2018.
[I-D.ietf-isis-segment-routing-extensions] [I-D.ietf-isis-segment-routing-extensions]
Previdi, S., Ginsberg, L., Filsfils, C., Bashandy, A., Previdi, S., Ginsberg, L., Filsfils, C., Bashandy, A.,
Gredler, H., Litkowski, S., Decraene, B., and J. Tantsura, Gredler, H., and B. Decraene, "IS-IS Extensions for
"IS-IS Extensions for Segment Routing", draft-ietf-isis- Segment Routing", draft-ietf-isis-segment-routing-
segment-routing-extensions-19 (work in progress), July extensions-22 (work in progress), December 2018.
2018.
[I-D.ietf-ospf-mpls-elc] [I-D.ietf-ospf-mpls-elc]
Xu, X., Kini, S., Sivabalan, S., Filsfils, C., and S. Xu, X., Kini, S., Sivabalan, S., Filsfils, C., and S.
Litkowski, "Signaling Entropy Label Capability and Entropy Litkowski, "Signaling Entropy Label Capability and Entropy
Readable Label-stack Depth Using OSPF", draft-ietf-ospf- Readable Label-stack Depth Using OSPF", draft-ietf-ospf-
mpls-elc-06 (work in progress), August 2018. mpls-elc-07 (work in progress), September 2018.
[I-D.ietf-ospf-segment-routing-extensions] [I-D.ietf-ospf-segment-routing-extensions]
Psenak, P., Previdi, S., Filsfils, C., Gredler, H., Psenak, P., Previdi, S., Filsfils, C., Gredler, H.,
Shakir, R., Henderickx, W., and J. Tantsura, "OSPF Shakir, R., Henderickx, W., and J. Tantsura, "OSPF
Extensions for Segment Routing", draft-ietf-ospf-segment- Extensions for Segment Routing", draft-ietf-ospf-segment-
routing-extensions-25 (work in progress), April 2018. routing-extensions-27 (work in progress), December 2018.
Internet-DrafSignaling MSD (Maximum SID Depth) using BGP-LS August 2018 [I-D.ietf-spring-segment-routing-mpls]
Bashandy, A., Filsfils, C., Previdi, S., Decraene, B.,
Litkowski, S., and R. Shakir, "Segment Routing with MPLS
data plane", draft-ietf-spring-segment-routing-mpls-18
(work in progress), December 2018.
Authors' Addresses Authors' Addresses
Jeff Tantsura Jeff Tantsura
Nuage Networks Apstra, Inc.
Email: jefftant.ietf@gmail.com Email: jefftant.ietf@gmail.com
Uma Chunduri Uma Chunduri
Huawei USA Huawei USA
Email: uma.chunduri@huawei.com Email: uma.chunduri@huawei.com
Greg Mirsky Greg Mirsky
ZTE Corp. ZTE Corp.
Email: gregimirsky@gmail.com Email: gregimirsky@gmail.com
Siva Sivabalan Siva Sivabalan
Cisco Cisco
Email: msiva@cisco.com Email: msiva@cisco.com
Nikos Triantafillis
Apstra, Inc.
Email: nikos@apstra.com
 End of changes. 27 change blocks. 
59 lines changed or deleted 40 lines changed or added

This html diff was produced by rfcdiff 1.47. The latest version is available from http://tools.ietf.org/tools/rfcdiff/