--- 1/draft-ietf-idr-bgp-ls-segment-routing-ext-04.txt 2018-04-10 03:13:14.055282823 -0700 +++ 2/draft-ietf-idr-bgp-ls-segment-routing-ext-05.txt 2018-04-10 03:13:14.191286091 -0700 @@ -1,23 +1,23 @@ Inter-Domain Routing S. Previdi, Ed. Internet-Draft K. Talaulikar Intended status: Standards Track C. Filsfils -Expires: July 29, 2018 Cisco Systems, Inc. +Expires: October 12, 2018 Cisco Systems, Inc. H. Gredler RtBrick Inc. M. Chen Huawei Technologies - January 25, 2018 + April 10, 2018 BGP Link-State extensions for Segment Routing - draft-ietf-idr-bgp-ls-segment-routing-ext-04 + draft-ietf-idr-bgp-ls-segment-routing-ext-05 Abstract Segment Routing (SR) allows for a flexible definition of end-to-end paths by encoding paths as sequences of topological sub-paths, called "segments". These segments are advertised by routing protocols e.g. by the link state routing protocols (IS-IS, OSPFv2 and OSPFv3) within IGP topologies. This draft defines extensions to the BGP Link-state address-family in @@ -37,21 +37,21 @@ Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - This Internet-Draft will expire on July 29, 2018. + This Internet-Draft will expire on October 12, 2018. Copyright Notice Copyright (c) 2018 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents @@ -63,21 +63,21 @@ Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 2. BGP-LS Extensions for Segment Routing . . . . . . . . . . . . 5 2.1. Node Attributes TLVs . . . . . . . . . . . . . . . . . . 5 2.1.1. SID/Label Sub-TLV . . . . . . . . . . . . . . . . . . 5 2.1.2. SR-Capabilities TLV . . . . . . . . . . . . . . . . . 6 2.1.3. SR-Algorithm TLV . . . . . . . . . . . . . . . . . . 7 2.1.4. SR Local Block TLV . . . . . . . . . . . . . . . . . 8 - 2.1.5. SRMS Preference TLV . . . . . . . . . . . . . . . . . 8 + 2.1.5. SRMS Preference TLV . . . . . . . . . . . . . . . . . 9 2.2. Link Attribute TLVs . . . . . . . . . . . . . . . . . . . 9 2.2.1. Adjacency SID TLV . . . . . . . . . . . . . . . . . . 10 2.2.2. LAN Adjacency SID TLV . . . . . . . . . . . . . . . . 10 2.2.3. L2 Bundle Member . . . . . . . . . . . . . . . . . . 11 2.3. Prefix Attribute TLVs . . . . . . . . . . . . . . . . . . 13 2.3.1. Prefix-SID TLV . . . . . . . . . . . . . . . . . . . 14 2.3.2. Prefix Attribute Flags TLV . . . . . . . . . . . . . 15 2.3.3. Source Router Identifier (Source Router-ID) TLV . . . 16 2.3.4. Range TLV . . . . . . . . . . . . . . . . . . . . . . 16 2.4. Equivalent IS-IS Segment Routing TLVs/Sub-TLVs . . . . . 17 @@ -90,24 +90,25 @@ 3.4. Advertisement of a range of IS-IS SR bindings . . . . . . 20 4. Implementation Status . . . . . . . . . . . . . . . . . . . . 20 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 21 5.1. TLV/Sub-TLV Code Points Summary . . . . . . . . . . . . . 21 6. Manageability Considerations . . . . . . . . . . . . . . . . 22 6.1. Operational Considerations . . . . . . . . . . . . . . . 22 6.1.1. Operations . . . . . . . . . . . . . . . . . . . . . 22 7. Security Considerations . . . . . . . . . . . . . . . . . . . 22 8. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 22 - 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 22 - 9.1. Normative References . . . . . . . . . . . . . . . . . . 23 - 9.2. Informative References . . . . . . . . . . . . . . . . . 24 - 9.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 25 + 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 22 + 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 23 + 10.1. Normative References . . . . . . . . . . . . . . . . . . 23 + 10.2. Informative References . . . . . . . . . . . . . . . . . 24 + 10.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 26 1. Introduction Segment Routing (SR) allows for a flexible definition of end-to-end paths by combining sub-paths called "segments". A segment can represent any instruction, topological or service-based. A segment can have a local semantic to an SR node or global within a domain. Within IGP topologies an SR path is encoded as a sequence of topological sub-paths, called "IGP segments". These segments are @@ -262,36 +263,39 @@ [I-D.ietf-ospf-segment-routing-extensions] and [I-D.ietf-ospf-ospfv3-segment-routing-extensions]. The SR Capabilities TLV has following format: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Flags | RESERVED | + | Flags | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Range Size | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ // SID/Label sub-TLV (variable) // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type: TBD, see Section 5. Length: Variable. Flags: 1 octet of flags as defined in [I-D.ietf-isis-segment-routing-extensions]. + Reserved: 1 octet that SHOULD be set to 0 and MUST be ignored on + receipt. + One or more entries, each of which have the following format: Range Size: 3 octet value indicating the number of labels in the range. SID/Label sub-TLV (as defined in Section 2.1.1). 2.1.3. SR-Algorithm TLV The SR-Algorithm TLV has the following format: @@ -325,35 +329,38 @@ range of local SIDs available, it is required that the node advertises its SRLB. The SRLB TLV has the following format: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Flags | RESERVED | + | Flags | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Range Size | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ // SID/Label sub-TLV (variable) // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Type: TBD, see Section 5. Length: Variable. Flags: 1 octet of flags. None are defined at this stage. + Reserved: 1 octet that SHOULD be set to 0 and MUST be ignored on + receipt. + One or more entries, each of which have the following format: Range Size: 3 octet value indicating the number of labels in the range. SID/Label sub-TLV (as defined in Section 2.1.1). 2.1.5. SRMS Preference TLV The Segment Routing Mapping Server (SRMS) Preference TLV is used in @@ -429,20 +436,23 @@ Length: Variable. Flags. 1 octet field of following flags as defined in [I-D.ietf-isis-segment-routing-extensions], [I-D.ietf-ospf-segment-routing-extensions] and [I-D.ietf-ospf-ospfv3-segment-routing-extensions]. Weight: Weight used for load-balancing purposes. + Reserved: 2 octets that SHOULD be set to 0 and MUST be ignored on + receipt. + SID/Index/Label: Label or index value depending on the flags setting as defined in [I-D.ietf-isis-segment-routing-extensions], [I-D.ietf-ospf-segment-routing-extensions] and [I-D.ietf-ospf-ospfv3-segment-routing-extensions]. 2.2.2. LAN Adjacency SID TLV The LAN Adjacency SID (LAN-Adj-SID-SID) TLV has the following format: 0 1 2 3 @@ -469,20 +479,23 @@ Length: Variable. Flags. 1 octet field of following flags as defined in [I-D.ietf-isis-segment-routing-extensions], [I-D.ietf-ospf-segment-routing-extensions] and [I-D.ietf-ospf-ospfv3-segment-routing-extensions]. Weight: Weight used for load-balancing purposes. + Reserved: 2 octets that SHOULD be set to 0 and MUST be ignored on + receipt. + SID/Index/Label: Label or index value depending on the flags setting as defined in [I-D.ietf-isis-segment-routing-extensions], [I-D.ietf-ospf-segment-routing-extensions] and [I-D.ietf-ospf-ospfv3-segment-routing-extensions]. 2.2.3. L2 Bundle Member The L2 Bundle Member Attribute TLV identifies an L2 Bundle Member link which in turn is associated with a parent L3 link. The L3 link is described by the Link NLRI defined in [RFC7752] and the L2 Bundle @@ -596,20 +609,23 @@ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ where: Type: TBD, see Section 5. Length: Variable Algorithm: 1 octet value identify the algorithm. + Reserved: 2 octets that SHOULD be set to 0 and MUST be ignored on + receipt. + SID/Index/Label: * IS-IS: Label or index value as defined in [I-D.ietf-isis-segment-routing-extensions], * OSPFv2: Label or index value as defined in [I-D.ietf-ospf-segment-routing-extensions], * OSPFv3: Label or index value as defined in [I-D.ietf-ospf-ospfv3-segment-routing-extensions], @@ -700,37 +716,40 @@ Range TLV is attached to MUST be advertised as a non-routing prefix where no IGP metric TLV (TLV 1095) is attached. The format of the Range TLV is as follows: 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ - | Flags | RESERVED | Range Size | + | Flags | Reserved | Range Size | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ // sub-TLVs // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ where: Figure 2: Range TLV format Type: TBD, see Section 5. Length is 4. Flags: as defined in [I-D.ietf-ospf-segment-routing-extensions], [I-D.ietf-ospf-ospfv3-segment-routing-extensions] and [I-D.ietf-isis-segment-routing-extensions]. + Reserved: 1 octet that SHOULD be set to 0 and MUST be ignored on + receipt. + Range Size: 2 octets as defined in [I-D.ietf-ospf-segment-routing-extensions]. Within the Range TLV, the Prefix-SID TLV (used as sub-TLV in this context) MAY be present. 2.4. Equivalent IS-IS Segment Routing TLVs/Sub-TLVs This section illustrate the IS-IS Segment Routing Extensions TLVs and sub-TLVs mapped to the ones defined in this document. @@ -963,43 +982,48 @@ Email: acee@cisco.com Saikat Ray Individual Email: raysaikat@gmail.com Jeff Tantsura Nuage Networks Email: jefftant.ietf@gmail.com -9. References -9.1. Normative References +9. Acknowledgements + + The authors would like to thank Jeffrey Haas for his review of this + document. + +10. References + +10.1. Normative References [I-D.ietf-idr-te-pm-bgp] - Ginsberg, L., Previdi, S., Wu, Q., Gredler, H., Ray, S., - Tantsura, J., and C. Filsfils, "BGP-LS Advertisement of - IGP Traffic Engineering Performance Metric Extensions", - draft-ietf-idr-te-pm-bgp-08 (work in progress), August - 2017. + Ginsberg, L., Previdi, S., Wu, Q., Tantsura, J., and C. + Filsfils, "BGP-LS Advertisement of IGP Traffic Engineering + Performance Metric Extensions", draft-ietf-idr-te-pm- + bgp-10 (work in progress), March 2018. [I-D.ietf-isis-segment-routing-extensions] Previdi, S., Ginsberg, L., Filsfils, C., Bashandy, A., Gredler, H., Litkowski, S., Decraene, B., and J. Tantsura, "IS-IS Extensions for Segment Routing", draft-ietf-isis- segment-routing-extensions-15 (work in progress), December 2017. [I-D.ietf-ospf-ospfv3-segment-routing-extensions] - Psenak, P., Previdi, S., Filsfils, C., Gredler, H., + Psenak, P., Filsfils, C., Previdi, S., Gredler, H., Shakir, R., Henderickx, W., and J. Tantsura, "OSPFv3 Extensions for Segment Routing", draft-ietf-ospf-ospfv3- - segment-routing-extensions-10 (work in progress), - September 2017. + segment-routing-extensions-11 (work in progress), January + 2018. [I-D.ietf-ospf-segment-routing-extensions] Psenak, P., Previdi, S., Filsfils, C., Gredler, H., Shakir, R., Henderickx, W., and J. Tantsura, "OSPF Extensions for Segment Routing", draft-ietf-ospf-segment- routing-extensions-24 (work in progress), December 2017. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, @@ -1028,21 +1052,21 @@ S. Ray, "North-Bound Distribution of Link-State and Traffic Engineering (TE) Information Using BGP", RFC 7752, DOI 10.17487/RFC7752, March 2016, . [RFC7794] Ginsberg, L., Ed., Decraene, B., Previdi, S., Xu, X., and U. Chunduri, "IS-IS Prefix Attributes for Extended IPv4 and IPv6 Reachability", RFC 7794, DOI 10.17487/RFC7794, March 2016, . -9.2. Informative References +10.2. Informative References [I-D.ietf-spring-segment-routing] Filsfils, C., Previdi, S., Ginsberg, L., Decraene, B., Litkowski, S., and R. Shakir, "Segment Routing Architecture", draft-ietf-spring-segment-routing-15 (work in progress), January 2018. [RFC4272] Murphy, S., "BGP Security Vulnerabilities Analysis", RFC 4272, DOI 10.17487/RFC4272, January 2006, . @@ -1056,21 +1080,21 @@ BGP, LDP, PCEP, and MSDP Issues According to the Keying and Authentication for Routing Protocols (KARP) Design Guide", RFC 6952, DOI 10.17487/RFC6952, May 2013, . [RFC7942] Sheffer, Y. and A. Farrel, "Improving Awareness of Running Code: The Implementation Status Section", BCP 205, RFC 7942, DOI 10.17487/RFC7942, July 2016, . -9.3. URIs +10.3. URIs [1] http://tools.ietf.org/html/draft-ietf-isis-segment-routing- extensions-05#section-3.1 [2] http://tools.ietf.org/html/draft-ietf-isis-segment-routing- extensions-05#section-3.2 [3] http://tools.ietf.org/html/draft-ietf-isis-segment-routing- extensions-05#section-2.2.1