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Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Outdated reference: A later version (-26) exists of draft-ietf-6man-segment-routing-header-19 == Outdated reference: A later version (-18) exists of draft-ietf-idr-bgp-ls-segment-routing-ext-15 == Outdated reference: A later version (-18) exists of draft-ietf-idr-bgp-ls-segment-routing-msd-04 == Outdated reference: A later version (-07) exists of draft-li-ospf-ospfv3-srv6-extensions-03 ** Obsolete normative reference: RFC 7752 (Obsoleted by RFC 9552) Summary: 1 error (**), 0 flaws (~~), 5 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Inter-Domain Routing G. Dawra, Ed. 3 Internet-Draft LinkedIn 4 Intended status: Standards Track C. Filsfils 5 Expires: December 2, 2019 K. Talaulikar, Ed. 6 Cisco Systems 7 M. Chen 8 Huawei 9 D. Bernier 10 Bell Canada 11 B. Decraene 12 Orange 13 May 31, 2019 15 BGP Link State Extensions for SRv6 16 draft-ietf-idr-bgpls-srv6-ext-00 18 Abstract 20 Segment Routing IPv6 (SRv6) allows for a flexible definition of end- 21 to-end paths within various topologies by encoding paths as sequences 22 of topological or functional sub-paths, called "segments". These 23 segments are advertised by the various protocols such as BGP, ISIS 24 and OSPFv3. 26 BGP Link-state (BGP-LS) address-family solution for SRv6 is similar 27 to BGP-LS for SR for MPLS dataplane. This draft defines extensions 28 to the BGP-LS to advertise SRv6 Segments along with their functions 29 and other attributes via BGP. 31 Requirements Language 33 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 34 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 35 "OPTIONAL" in this document are to be interpreted as described in BCP 36 14 [RFC2119] [RFC8174] when, and only when, they appear in all 37 capitals, as shown here. 39 Status of This Memo 41 This Internet-Draft is submitted in full conformance with the 42 provisions of BCP 78 and BCP 79. 44 Internet-Drafts are working documents of the Internet Engineering 45 Task Force (IETF). Note that other groups may also distribute 46 working documents as Internet-Drafts. The list of current Internet- 47 Drafts is at https://datatracker.ietf.org/drafts/current/. 49 Internet-Drafts are draft documents valid for a maximum of six months 50 and may be updated, replaced, or obsoleted by other documents at any 51 time. It is inappropriate to use Internet-Drafts as reference 52 material or to cite them other than as "work in progress." 54 This Internet-Draft will expire on December 2, 2019. 56 Copyright Notice 58 Copyright (c) 2019 IETF Trust and the persons identified as the 59 document authors. All rights reserved. 61 This document is subject to BCP 78 and the IETF Trust's Legal 62 Provisions Relating to IETF Documents 63 (https://trustee.ietf.org/license-info) in effect on the date of 64 publication of this document. Please review these documents 65 carefully, as they describe your rights and restrictions with respect 66 to this document. Code Components extracted from this document must 67 include Simplified BSD License text as described in Section 4.e of 68 the Trust Legal Provisions and are provided without warranty as 69 described in the Simplified BSD License. 71 Table of Contents 73 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 74 2. BGP-LS Extensions for SRv6 . . . . . . . . . . . . . . . . . 4 75 3. SRv6 Node Attributes . . . . . . . . . . . . . . . . . . . . 5 76 3.1. SRv6 Capabilities TLV . . . . . . . . . . . . . . . . . . 5 77 3.2. SRv6 Node MSD Types . . . . . . . . . . . . . . . . . . . 6 78 4. SRv6 Link Attributes . . . . . . . . . . . . . . . . . . . . 7 79 4.1. SRv6 End.X SID TLV . . . . . . . . . . . . . . . . . . . 7 80 4.2. SRv6 LAN End.X SID TLV . . . . . . . . . . . . . . . . . 9 81 4.3. SRv6 Link MSD Types . . . . . . . . . . . . . . . . . . . 11 82 5. SRv6 Prefix Attributes . . . . . . . . . . . . . . . . . . . 11 83 5.1. SRv6 Locator TLV . . . . . . . . . . . . . . . . . . . . 11 84 6. SRv6 SID NLRI . . . . . . . . . . . . . . . . . . . . . . . . 13 85 6.1. SRv6 SID Information TLV . . . . . . . . . . . . . . . . 15 86 7. SRv6 SID Attributes . . . . . . . . . . . . . . . . . . . . . 15 87 7.1. SRv6 Endpoint Function TLV . . . . . . . . . . . . . . . 15 88 7.2. SRv6 BGP Peer Node SID TLV . . . . . . . . . . . . . . . 16 89 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 18 90 8.1. BGP-LS NLRI-Types . . . . . . . . . . . . . . . . . . . . 18 91 8.2. BGP-LS TLVs . . . . . . . . . . . . . . . . . . . . . . . 18 92 9. Manageability Considerations . . . . . . . . . . . . . . . . 19 93 10. Operational Considerations . . . . . . . . . . . . . . . . . 19 94 10.1. Operations . . . . . . . . . . . . . . . . . . . . . . . 19 95 11. Security Considerations . . . . . . . . . . . . . . . . . . . 19 96 12. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 19 97 13. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 20 98 14. References . . . . . . . . . . . . . . . . . . . . . . . . . 20 99 14.1. Normative References . . . . . . . . . . . . . . . . . . 20 100 14.2. Informative References . . . . . . . . . . . . . . . . . 22 101 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22 103 1. Introduction 105 SRv6 refers to Segment Routing instantiated on the IPv6 dataplane 106 [RFC8402]. Segment Identifier (SID) is often used as a shorter 107 reference for "SRv6 Segment". 109 The network programming paradigm 110 [I-D.filsfils-spring-srv6-network-programming] is central to SRv6. 111 It describes how different functions can be bound to their SIDs and 112 how a network program can be expressed as a combination of SIDs. 114 An SRv6-capable node N maintains a "My SID Table" (refer 115 [I-D.filsfils-spring-srv6-network-programming]). This table contains 116 all the SRv6 segments explicitly instantiated at node N. 118 The IS-IS [I-D.bashandy-isis-srv6-extensions] and OSPFv3 119 [I-D.li-ospf-ospfv3-srv6-extensions] link-state routing protocols 120 have been extended to advertise some of these SRv6 SIDs and 121 SRv6-related information. BGP ([I-D.dawra-idr-srv6-vpn]) has been 122 extended to advertise some of these SRv6 SIDs for VPN services. 123 Certain other SRv6 SIDs may be instantiated on a node via other 124 mechanisms for topological or service functionalities. 126 The advertisement of SR related information along with the topology 127 for the MPLS dataplane instantiation is specified in 128 [I-D.ietf-idr-bgp-ls-segment-routing-ext] and for the BGP Egress Peer 129 Engineering (EPE) is specified in 130 [I-D.ietf-idr-bgpls-segment-routing-epe]. On the similar lines, 131 introducing the SRv6 related information in BGP-LS allows it's 132 consumer applications that require topological visibility to also 133 receive the "My SID Table" from nodes across a domain or even across 134 Autonomous Systems (AS), as required. This allows applications to 135 leverage the SRv6 capabilities for network programming. 137 The identifying key of each Link-State object, namely a node, link, 138 or prefix, is encoded in the NLRI and the properties of the object 139 are encoded in the BGP-LS Attribute [RFC7752]. 141 This document describes extensions to BGP-LS to advertise the SRv6 142 "My SID Table" and other SRv6 information from all the SRv6 capable 143 nodes in the domain when sourced from link-state routing protocols 144 and directly from individual SRv6 capable nodes when sourced from 145 BGP. 147 2. BGP-LS Extensions for SRv6 149 BGP-LS[RFC7752] defines the BGP Node, Link and Prefix attributes. 150 All non-VPN link, node, and prefix information SHALL be encoded using 151 AFI 16388 / SAFI 71. VPN link, node, and prefix information SHALL be 152 encoded using AFI 16388 / SAFI 72. 154 The SRv6 information pertaining to a node is advertised via the BGP- 155 LS Node NLRI and using the BGP-LS Attribute TLVs as follows: 157 o SRv6 Capabilities of the node is advertised via a new SRv6 158 Capabilities TLV 160 o New MSD types introduced for SRv6 are advertised as new sub-TLVs 161 of the Node MSD TLV specified in 162 [I-D.ietf-idr-bgp-ls-segment-routing-msd]. 164 o Algorithm support for SRv6 is advertised via the existing SR 165 Algorithm TLV specified in 166 [I-D.ietf-idr-bgp-ls-segment-routing-ext]. 168 The SRv6 information pertaining to a link is advertised via the BGP- 169 LS Link NLRI and using the BGP-LS Attribute TLVs as follows: 171 o SRv6 End.X SID of the link state routing adjacency or the BGP EPE 172 Peer Adjacency is advertised via a new SRv6 End.X SID TLV 174 o SRv6 LAN End.X SID of the link state routing adjacency to a non- 175 DR/DIS router is advertised via a new SRv6 LAN End.X SID TLV 177 o New MSD types introduced for SRv6 are advertised as new sub-TLVs 178 of the Link MSD TLV specified in 179 [I-D.ietf-idr-bgp-ls-segment-routing-msd]. 181 The SRv6 Locator information of a node is advertised via the BGP-LS 182 Prefix NLRI using the new SRv6 Locator TLV in the BGP-LS Attribute. 184 The SRv6 SIDs associated with the node from its "My SID Table" are 185 advertised as a newly introduce BGP-LS SRv6 SID NLRI. This enables 186 the BGP-LS encoding to scale to cover a potentially large set of SRv6 187 SIDs instantiated on a node with the granularity of individual SIDs 188 and without affecting the size and scalability of the BGP-LS updates. 189 New BGP-LS Attribute TLVs are introduced for the SRv6 SID NLRI as 190 follows: 192 o The endpoint function of the SRv6 SID is advertised via a new SRv6 193 Endpoint Function TLV 195 o The BGP EPE Peer Node and Peer Set SID context is advertised via a 196 new SRv6 BGP EPE Peer Node SID TLV 198 When the BGP-LS router is advertising topology information that it 199 sources from the underlying link-state routing protocol, then it maps 200 the corresponding SRv6 information from the SRv6 extensions for IS-IS 201 [I-D.bashandy-isis-srv6-extensions] and OSPFv3 202 [I-D.li-ospf-ospfv3-srv6-extensions] protocols to their BGP-LS TLVs/ 203 sub-TLVs for all SRv6 capable nodes in that routing protocol domain. 204 When the BGP-LS router is advertising topology information from the 205 BGP routing protocol [I-D.ietf-idr-bgpls-segment-routing-epe], then 206 it advertises the SRv6 information from the local node alone (e.g. 207 BGP EPE topology information or in the case of a data center network 208 running BGP as the only routing protocol). 210 Subsequent sections of this document specify the encoding of the 211 newly defined extensions. 213 3. SRv6 Node Attributes 215 SRv6 attributes of a node are advertised using the new BGP-LS 216 Attribute TLVs defined in this section and associated with the BGP-LS 217 Node NLRI. 219 3.1. SRv6 Capabilities TLV 221 This BGP-LS Attribute TLV is used to announce the SRv6 capabilities 222 of the node along with the BGP-LS Node NLRI and indicates the SRv6 223 support by the node. A single instance of this TLV MUST be included 224 in the BGP-LS attribute for each SRv6 capable node. This TLV maps to 225 the SRv6 Capabilities sub-TLV and the SRv6 Capabilities TLV of the 226 IS-IS and OSPFv3 protocol SRv6 extensions respectively. 228 0 1 2 3 229 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 1 230 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 231 | Type | Length | 232 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 233 | Flags | Reserved | 234 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 236 Figure 1: SRv6 Capabilities TLV Format 238 Where: 240 o Type: 2 octet field with value TBD, see Section 8. 242 o Length : 2 octet field with value set to 4. 244 o Flags: 2 octet field. The following flags are defined: 246 0 1 247 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 248 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 249 | |O| | 250 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 252 Figure 2: SRv6 Capability TLV Flags Format 254 * O-flag: If set, then router is capable of supporting SRH O-bit 255 Flags, as specified in [I-D.ali-spring-srv6-oam]. 257 o Reserved: 2 octet that SHOULD be set to 0 and MUST be ignored on 258 receipt. 260 3.2. SRv6 Node MSD Types 262 The Node MSD TLV [I-D.ietf-idr-bgp-ls-segment-routing-msd] of the 263 BGP-LS Attribute of the Node NLRI is also used to advertise the 264 limits and the supported Segment Routing Header (SRH) 265 [I-D.ietf-6man-segment-routing-header] operations supported by the 266 SRv6 capable node. The SRv6 MSD Types specified in 267 [I-D.bashandy-isis-srv6-extensions] are also used with the BGP-LS 268 Node MSD TLV as these codepoints are shared between IS-IS, OSPF and 269 BGP-LS protocols. The description and semantics of these new MSD 270 types for BGP-LS are identical as specified 271 [I-D.bashandy-isis-srv6-extensions] and summarized in the table 272 below: 274 +----------+------------------------------+ 275 | MSD Type | Description | 276 +----------+------------------------------+ 277 | TBD | Maximum Segments Left | 278 | TBD | Maximum End Pop | 279 | TBD | Maximum T.Insert | 280 | TBD | Maximum T.Encaps | 281 | TBD | Maximum End D | 282 +----------+------------------------------+ 284 Figure 3: SRv6 Node MSD Types 286 Each MSD type is encoded as a one octet type followed by a one octet 287 value. 289 4. SRv6 Link Attributes 291 SRv6 attributes and SIDs associated with a link or adjacency are 292 advertised using the new BGP-LS Attribute TLVs defined in this 293 section and associated with the BGP-LS Link NLRI. 295 4.1. SRv6 End.X SID TLV 297 The SRv6 End.X SID TLV is used to advertise the SRv6 End.X SIDs that 298 correspond to a point-to-point or point-to-multipoint link or 299 adjacency of the local node for IS-IS and OSPFv3 protocols. This TLV 300 can also be used to advertise the End.X function SRv6 SID 301 corresponding to the underlying layer-2 member links for a layer-3 302 bundle interface using L2 Bundle Member Attribute TLV as specified in 303 [I-D.ietf-idr-bgp-ls-segment-routing-ext] . 305 For the nodes running BGP routing protocol, this TLV is used to 306 advertise the BGP EPE Peer Adjacency SID for SRv6 on the same lines 307 as specified for SR/MPLS in [I-D.ietf-idr-bgpls-segment-routing-epe]. 308 The SRv6 End.X SID for the BGP Peer Adjacency indicates the cross- 309 connect to a specific layer-3 link to the specific BGP session peer 310 (neighbor). 312 The TLV has the following format: 314 0 1 2 3 315 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 1 316 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 317 | Type | Length | 318 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 319 | SRv6 Endpoint Function | Flags | Algorithm | 320 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 321 | Weight | Reserved | SID (16 octets) ... 322 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 323 SID (cont ...) 324 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 325 SID (cont ...) 326 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 327 SID (cont ...) 328 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 329 SID (cont ...) | Sub-TLVs (variable) . . . 330 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 332 Figure 4: SRv6 End.X TLV Format 334 Where: 336 Type: 2 octet field with value TBD, see Section 8. 338 Length: 2 octet field with the total length of the value portion 339 of the TLV. 341 Function Code: 2 octet field. The Endpoint Function code point 342 for this SRv6 SID as defined in 343 [I-D.filsfils-spring-srv6-network-programming]. 345 Flags: 1 octet of flags with the following definition: 347 0 1 2 3 4 5 6 7 348 +-+-+-+-+-+-+-+-+ 349 |B|S|P| Rsvd | 350 +-+-+-+-+-+-+-+-+ 352 Figure 5: SRv6 End.X SID TLV Flags Format 354 * B-Flag: Backup Flag. If set, the SID is eligible for 355 protection (e.g. using IPFRR) as described in [RFC8355]. 357 * S-Flag: Set Flag. When set, the S-Flag indicates that the SID 358 refers to a set of adjacencies (and therefore MAY be assigned 359 to other adjacencies as well). 361 * P-Flag: Persistent Flag: When set, the P-Flag indicates that 362 the SID is persistently allocated, i.e., the value remains 363 consistent across router restart and/or interface flap. 365 * Rsvd bits: Reserved for future use and MUST be zero when 366 originated and ignored when received. 368 Algorithm: 1 octet field. Algorithm associated with the SID. 369 Algorithm values are defined in the IGP Algorithm Type registry. 371 Weight: 1 octet field. The value represents the weight of the SID 372 for the purpose of load balancing. The use of the weight is 373 defined in [RFC8402]. 375 Reserved: 1 octet field that SHOULD be set to 0 and MUST be 376 ignored on receipt. 378 SID: 16 octet field. This field encodes the advertised SRv6 SID 379 as 128 bit value. 381 Sub-TLVs : currently none defined. Used to advertise sub-TLVs 382 that provide additional attributes for the given SRv6 End.X SID. 384 4.2. SRv6 LAN End.X SID TLV 386 For a LAN interface, normally a node only announces its adjacency to 387 the IS-IS pseudo-node (or the equivalent OSPF Designated Router). 388 The SRv6 LAN End.X SID TLV allows a node to announce SRv6 SID 389 corresponding to functions like END.X for its adjacencies to all 390 other (i.e. non-DIS or non-DR) nodes attached to the LAN in a single 391 instance of the BGP-LS Link NLRI. Without this TLV, the 392 corresponding BGP-LS link NLRI would need to be originated for each 393 additional adjacency in order to advertise the SRv6 End.X SID TLVs 394 for these neighbor adjacencies. 396 The IS-IS and OSPFv3 SRv6 LAN End.X SID TLVs have the following 397 format: 399 0 1 2 3 400 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 1 401 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 402 | Type | Length | 403 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 404 | SRv6 Endpoint Function | Flags | Algorithm | 405 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 406 | Weight | Reserved | ISIS System-ID (6 octets) | 407 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 408 | or OSPFv3 Router-ID (4 octets) of the neighbor | 409 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 410 | SID (16 octets) ... 411 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 412 SID (cont ...) 413 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 414 SID (cont ...) 415 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 416 SID (cont ...) | 417 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 418 | Sub-TLVs (variable) . . . 419 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 421 Figure 6: SRv6 LAN End.X SID TLV Format 423 Where: 425 o Type: 2 octet field with value TBD in case of IS-IS and TBD in 426 case of OSPFv3, see Section 8. 428 o Length: 2 octet field with the total length of the value portion 429 of the TLV. 431 o Function Code: 2 octet field. The Endpoint Function code point 432 for this SRv6 SID as defined in 433 [I-D.filsfils-spring-srv6-network-programming]. 435 o Flags: 1 octet of flags with the following definition: 437 0 1 2 3 4 5 6 7 438 +-+-+-+-+-+-+-+-+ 439 |B|S|P| Rsvd | 440 +-+-+-+-+-+-+-+-+ 442 Figure 7: SRv6 LAN End.X SID TLV Flags Format 444 * B-Flag: Backup Flag. If set, the SID is eligible for 445 protection (e.g. using IPFRR) as described in [RFC8355]. 447 * S-Flag: Set Flag. When set, the S-Flag indicates that the SID 448 refers to a set of adjacencies (and therefore MAY be assigned 449 to other adjacencies as well). 451 * P-Flag: Persistent Flag: When set, the P-Flag indicates that 452 the SID is persistently allocated, i.e., the value remains 453 consistent across router restart and/or interface flap. 455 * Rsvd bits: Reserved for future use and MUST be zero when 456 originated and ignored when received. 458 o Algorithm: 1 octet field. Algorithm associated with the SID. 459 Algorithm values are defined in the IGP Algorithm Type registry. 461 o Weight: 1 octet field. The value represents the weight of the SID 462 for the purpose of load balancing. The use of the weight is 463 defined in [RFC8402]. 465 o Reserved: 1 octet field that SHOULD be set to 0 and MUST be 466 ignored on receipt. 468 o Neighbor ID : 6 octets of ISIS System ID of the neighbor for the 469 ISIS SRv6 LAN End.X SID TLV and 4 octets of OSPFv3 Router-id of 470 the neighbor for the OSPFv3 SRv6 LAN End.X SID TLV. 472 o SID: 16 octet field. This field encodes the advertised SRv6 SID 473 as 128 bit value. 475 o Sub-TLVs : currently none defined. Used to advertise sub-TLVs 476 that provide additional attributes for the given SRv6 LAN End.X 477 SID. 479 4.3. SRv6 Link MSD Types 481 The Link MSD TLV [I-D.ietf-idr-bgp-ls-segment-routing-msd] of the 482 BGP-LS Attribute of the Link NLRI is also used to advertise the 483 limits and the supported Segment Routing Header (SRH) operations 484 supported on the specific link by the SRv6 capable node. The SRv6 485 MSD Types specified in [I-D.bashandy-isis-srv6-extensions] are also 486 used with the BGP-LS Link MSD TLV as these codepoints are shared 487 between IS-IS, OSPF and BGP-LS protocols. The description and 488 semantics of these new MSD types for BGP-LS are identical as 489 specified [I-D.bashandy-isis-srv6-extensions] and summarized in the 490 table below: 492 +----------+------------------------------+ 493 | MSD Type | Description | 494 +----------+------------------------------+ 495 | TBD | Maximum Segments Left | 496 | TBD | Maximum End Pop | 497 | TBD | Maximum T.Insert | 498 | TBD | Maximum T.Encaps | 499 | TBD | Maximum End D | 500 +----------+------------------------------+ 502 Figure 8: SRv6 Link MSD Types 504 Each MSD type is encoded as a one octet type followed by a one octet 505 value. 507 5. SRv6 Prefix Attributes 509 SRv6 attributes with an IPv6 prefix are advertised using the new BGP- 510 LS Attribute TLVs defined in this section and associated with the 511 BGP-LS Prefix NLRI. 513 5.1. SRv6 Locator TLV 515 As described in [I-D.filsfils-spring-srv6-network-programming], an 516 SRv6 SID is 128 bits and represented as 518 LOC:FUNCT 520 where LOC (the locator portion) is the L most significant bits and 521 FUNCT is the 128-L least significant bits. L is called the locator 522 length and is flexible. A node is provisioned with one or more 523 locators supported by that node. Locators are covering prefixes for 524 the set of SIDs provisioned on that node. These Locators are 525 advertised as BGP-LS Prefix NLRI objects along with the SRv6 Locator 526 TLV in its BGP-LS Attribute. 528 The IPv6 Prefix matching the Locator MAY be also advertised as a 529 prefix reachability by the underlying routing protocol. In this 530 case, the Prefix NLRI would be also associated with the Prefix Metric 531 TLV that carries the routing metric for this prefix. When the 532 Locator prefix is not being advertised as a prefix reachability, then 533 the Prefix NLRI would have the SRv6 Locator TLV associated with it 534 but no Prefix Metric TLV. In the absence of Prefix Metric TLV, the 535 consumer of the BGP-LS topology information MUST NOT interpret the 536 Locator prefix as a prefix reachability routing advertisement. 538 The SRv6 Locator TLV has the following format: 540 0 1 2 3 541 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 1 542 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 543 | Type | Length | 544 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 545 | Flags | Algorithm | Reserved | 546 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 547 | Metric | 548 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 549 | Sub-TLVs (variable) . . . 550 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 552 Figure 9: SRv6 Locator TLV Format 554 Where: 556 Type: 2 octet field with value TBD, see Section 8. 558 Length: 2 octet field with the total length of the value portion 559 of the TLV. 561 Flags: 1 octet of flags with the following definition: 563 0 1 2 3 4 5 6 7 564 +-+-+-+-+-+-+-+-+ 565 |D|A| Reserved | 566 +-+-+-+-+-+-+-+-+ 568 Figure 10: SRv6 Locator TLV Flags Format 570 * D-Flag: Indicates that the locator has been leaked into the IGP 571 domain when set. IS-IS operations for this are discussed in 572 [I-D.bashandy-isis-srv6-extensions]. 574 * A-Flag: When the Locator is associated with anycast 575 destinations, the A flag SHOULD be set. Otherwise, this bit 576 MUST be clear. 578 * Reserved bits: Reserved for future use and MUST be zero when 579 originated and ignored when received. 581 Algorithm: 1 octet field. Algorithm associated with the SID. 582 Algorithm values are defined in the IGP Algorithm Type registry. 584 Reserved: 2 octet field. The value MUST be zero when originated 585 and ignored when received. 587 Metric: 4 octet field. The value of the metric for the Locator. 589 Sub-TLVs : currently none defined. Used to advertise sub-TLVs 590 that provide additional attributes for the given SRv6 Locator. 592 6. SRv6 SID NLRI 594 SRv6 SID information is advertised in BGP UPDATE messages using the 595 MP_REACH_NLRI and MP_UNREACH_NLRI attributes [RFC4760]. The "Link- 596 State NLRI" defined in [RFC7752] is extended to carry the SRv6 SID 597 information. 599 A new "Link-State NLRI Type" is defined for SRv6 SID information as 600 following: 602 o Link-State NLRI Type: SRv6 SID NLRI (value TBD see IANA 603 Considerations Section 8.1). 605 The format of this new NLRI type is as shown in the following figure: 607 0 1 2 3 608 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 1 609 +-+-+-+-+-+-+-+-+ 610 | Protocol-ID | 611 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 612 | Identifier | 613 | (64 bits) | 614 ++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| 615 | Local Node Descriptors (variable) // 616 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 617 | SRv6 SID Descriptors (variable) // 618 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 620 Figure 11: SRv6 SID NLRI Format 622 Where: 624 o Protocol-ID: 1 octet field that specifies the protocol component 625 through which BGP-LS learns the SRv6 SIDs of the node. The 626 following Protocol-IDs apply to the SRv6 SID NLRI: 628 +-------------+----------------------------------+ 629 | Protocol-ID | NLRI information source protocol | 630 +-------------+----------------------------------+ 631 | 1 | IS-IS Level 1 | 632 | 2 | IS-IS Level 2 | 633 | 4 | Direct | 634 | 5 | Static configuration | 635 | 6 | OSPFv3 | 636 | 7 | BGP | 637 +-------------+----------------------------------+ 639 Figure 12: Protocol IDs for SRv6 SID NLRI 641 o Identifier: 8 octet value as defined in [RFC7752]. 643 o Local Node Descriptors TLV: as defined in [RFC7752] for IGPs, 644 local and static configuration and as defined in 645 [I-D.ietf-idr-bgpls-segment-routing-epe] for BGP protocol. 647 o SRv6 SID Descriptors: MUST include the SRv6 SID Information TLV 648 defined in Section 6.1 and optionally MAY include the Multi- 649 Topology Identifier TLV as defined in [RFC7752]. 651 New TLVs carried in the BGP Link State Attribute defined in [RFC7752] 652 are also defined in order to carry the attributes of a SRv6 SID in 653 Section 7. 655 6.1. SRv6 SID Information TLV 657 A SRv6 SID is a 128 bit value 658 [I-D.filsfils-spring-srv6-network-programming] and is encoded using 659 the SRv6 SID Information TLV. 661 The TLV has the following format: 663 0 1 2 3 664 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 1 665 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 666 | Type | Length | 667 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 668 | SID (16 octets) ... 669 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 670 SID (cont ...) 671 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 672 SID (cont ...) 673 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 674 SID (cont ...) | 675 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 677 Figure 13: SRv6 SID Information TLV Format 679 Where: 681 Type: 2 octet field with value TBD, see Section 8. 683 Length: 2 octet field with value set to 16. 685 SID: 16 octet field. This field encodes the advertised SRv6 SID 686 as 128 bit value. 688 7. SRv6 SID Attributes 690 This section specifies the new TLVs to be carried in the BGP Link 691 State Attribute associated with the BGP-LS SRv6 SID NLRI. 693 7.1. SRv6 Endpoint Function TLV 695 Each SRv6 SID instantiated in the "My SID Table" of an SRv6 capable 696 node has a specific instruction bound to it. A set of well-known 697 functions that can be associated with a SID are defined in 698 [I-D.filsfils-spring-srv6-network-programming]. 700 The SRv6 Endpoint Function TLV is a mandatory TLV that MUST be 701 included in the BGP-LS Attribute associated with the BGP-LS SRv6 SID 702 NLRI. The TLV has the following format: 704 0 1 2 3 705 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 1 706 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 707 | Type | Length | 708 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 709 | SRv6 Endpoint Function | Flags | Algorithm | 710 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 712 Figure 14: SRv6 Endpoint Function TLV 714 Where: 716 Type: 2 octet field with value TBD, see Section 8. 718 Length: 2 octet field with the value 4. 720 Function Code: 2 octet field. The Endpoint Function code point 721 for this SRv6 SID as defined in 722 [I-D.filsfils-spring-srv6-network-programming]. 724 Flags: 1 octet of flags with the none defined currently. Reserved 725 for future use and MUST be zero when originated and ignored when 726 received. 728 Algorithm: 1 octet field. Algorithm associated with the SID. 729 Algorithm values are defined in the IGP Algorithm Type registry. 731 7.2. SRv6 BGP Peer Node SID TLV 733 The BGP Peer Node SID and Peer Set SID for SR with MPLS dataplane are 734 specified in [I-D.ietf-idr-bgpls-segment-routing-epe]. The similar 735 Peer Node and Peer Set SID functionality can be realized with SRv6 736 using the END.X SRv6 SID. The SRv6 BGP Peer Node SID TLV is an 737 optional TLV for use in the BGP-LS Attribute for an SRv6 SID NLRI 738 corresponding to BGP protocol. This TLV MUST be included along with 739 SRv6 End.X SID that is associated with the BGP Peer Node or Peer Set 740 functionality. 742 The TLV has the following format: 744 0 1 2 3 745 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 1 746 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 747 | Type | Length | 748 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 749 | Flags | Weight | Reserved | 750 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 751 | Peer AS Number | 752 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 753 | Peer BGP Identifier | 754 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 756 Figure 15: SRv6 BGP Peer Node SID TLV Format 758 Where: 760 o Type: 2 octet field with value TBD, see Section 8. 762 o Length: 2 octet field with the value 12. 764 o Flags: 1 octet of flags with the following definition: 766 0 1 2 3 4 5 6 7 767 +-+-+-+-+-+-+-+-+ 768 |B|S|P| Rsvd | 769 +-+-+-+-+-+-+-+-+ 771 Figure 16: SRv6 BGP Peer End.X SID TLV Flags Format 773 * B-Flag: Backup Flag. If set, the SID is eligible for 774 protection (e.g. using IPFRR) as described in [RFC8355]. 776 * S-Flag: Set Flag. When set, the S-Flag indicates that the SID 777 refers to a set of BGP peering sessions (i.e. BGP Peer Set SID 778 functionality) and therefore MAY be assigned to one or more 779 End.X SIDs associated with BGP peer sessions. 781 * P-Flag: Persistent Flag: When set, the P-Flag indicates that 782 the SID is persistently allocated, i.e., the value remains 783 consistent across router restart and/or session flap. 785 * Rsvd bits: Reserved for future use and MUST be zero when 786 originated and ignored when received. 788 o Weight: 1 octet field. The value represents the weight of the SID 789 for the purpose of load balancing. The use of the weight is 790 defined in [RFC8402]. 792 o Peer AS Number : 4 octets of BGP AS number of the peer router. 794 o Peer BGP Identifier : 4 octets of the BGP Identifier (BGP Router- 795 ID) of the peer router. 797 For a SRv6 BGP EPE Peer Node SID, one instance of this TLV is 798 associated with the SRv6 SID. For SRv6 BGP EPE Peer Set SID, 799 multiple instances of this TLV (one for each peer in the "peer set") 800 are associated with the SRv6 SID and the S (set/group) flag is SET. 802 8. IANA Considerations 804 This document requests assigning code-points from the IANA "Border 805 Gateway Protocol - Link State (BGP-LS) Parameters" registry as 806 described in the sub-sections below. 808 8.1. BGP-LS NLRI-Types 810 The following codepoints is suggested (to be assigned by IANA) from 811 within the sub-registry called "BGP-LS NLRI-Types": 813 +------+----------------------------+---------------+ 814 | Type | NLRI Type | Reference | 815 +------+----------------------------+---------------+ 816 | TBD | SRv6 SID | this document | 817 +------+----------------------------+---------------+ 819 Figure 17: SRv6 SID NLRI Type Codepoint 821 8.2. BGP-LS TLVs 823 The following TLV codepoints are suggested (to be assigned by IANA) 824 from within the sub-registry called "BGP-LS Node Descriptor, Link 825 Descriptor, Prefix Descriptor, and Attribute TLVs": 827 +----------+----------------------------------------+---------------+ 828 | TLV Code | Description | Value defined | 829 | Point | | in | 830 +----------+----------------------------------------+---------------+ 831 | TBD | SRv6 Capabilities TLV | this document | 832 | TBD | SRv6 End.X SID TLV | this document | 833 | TBD | IS-IS SRv6 LAN End.X SID TLV | this document | 834 | TBD | OSPFv3 SRv6 LAN End.X SID TLV | this document | 835 | TBD | SRv6 Locator TLV | this document | 836 | TBD | SRv6 SID Information TLV | this document | 837 | TBD | SRv6 Endpoint Function TLV | this document | 838 | TBD | SRv6 BGP Peer Node SID TLV | this document | 839 +----------+----------------------------------------+---------------+ 841 Figure 18: SRv6 BGP-LS Attribute TLV Codepoints 843 9. Manageability Considerations 845 This section is structured as recommended in[RFC5706] 847 10. Operational Considerations 849 10.1. Operations 851 Existing BGP and BGP-LS operational procedures apply. No additional 852 operation procedures are defined in this document. 854 11. Security Considerations 856 Procedures and protocol extensions defined in this document do not 857 affect the BGP security model. See the 'Security Considerations' 858 section of [RFC4271] for a discussion of BGP security. Also refer 859 to[RFC4272] and [RFC6952] for analysis of security issues for BGP. 861 12. Contributors 863 James Uttaro 864 AT&T 865 USA 866 Email: ju1738@att.com 868 Hani Elmalky 869 Ericsson 870 USA 871 Email: hani.elmalky@gmail.com 872 Arjun Sreekantiah 873 Individual 874 USA 875 Email: arjunhrs@gmail.com 877 Les Ginsberg 878 Cisco Systems 879 USA 880 Email: ginsberg@cisco.com 882 Shunwan Zhuang 883 Huawei 884 China 885 Email: zhuangshunwan@huawei.com 887 13. Acknowledgements 889 The authors would like to thank Peter Psenak and Arun Babu for their 890 review of this document and their comments. 892 14. References 894 14.1. Normative References 896 [I-D.ali-spring-srv6-oam] 897 Ali, Z., Filsfils, C., Kumar, N., Pignataro, C., 898 faiqbal@cisco.com, f., Gandhi, R., Leddy, J., Matsushima, 899 S., Raszuk, R., daniel.voyer@bell.ca, d., Dawra, G., 900 Peirens, B., Chen, M., and G. Naik, "Operations, 901 Administration, and Maintenance (OAM) in Segment Routing 902 Networks with IPv6 Data plane (SRv6)", draft-ali-spring- 903 srv6-oam-02 (work in progress), October 2018. 905 [I-D.bashandy-isis-srv6-extensions] 906 Psenak, P., Filsfils, C., Bashandy, A., Decraene, B., and 907 Z. Hu, "IS-IS Extensions to Support Routing over IPv6 908 Dataplane", draft-bashandy-isis-srv6-extensions-05 (work 909 in progress), March 2019. 911 [I-D.dawra-idr-srv6-vpn] 912 Dawra, G., Filsfils, C., Dukes, D., Brissette, P., 913 Camarillo, P., Leddy, J., daniel.voyer@bell.ca, d., 914 daniel.bernier@bell.ca, d., Steinberg, D., Raszuk, R., 915 Decraene, B., Matsushima, S., and S. Zhuang, "BGP 916 Signaling for SRv6 based Services.", draft-dawra-idr- 917 srv6-vpn-05 (work in progress), October 2018. 919 [I-D.filsfils-spring-srv6-network-programming] 920 Filsfils, C., Camarillo, P., Leddy, J., 921 daniel.voyer@bell.ca, d., Matsushima, S., and Z. Li, "SRv6 922 Network Programming", draft-filsfils-spring-srv6-network- 923 programming-07 (work in progress), February 2019. 925 [I-D.ietf-6man-segment-routing-header] 926 Filsfils, C., Dukes, D., Previdi, S., Leddy, J., 927 Matsushima, S., and d. daniel.voyer@bell.ca, "IPv6 Segment 928 Routing Header (SRH)", draft-ietf-6man-segment-routing- 929 header-19 (work in progress), May 2019. 931 [I-D.ietf-idr-bgp-ls-segment-routing-ext] 932 Previdi, S., Talaulikar, K., Filsfils, C., Gredler, H., 933 and M. Chen, "BGP Link-State extensions for Segment 934 Routing", draft-ietf-idr-bgp-ls-segment-routing-ext-15 935 (work in progress), May 2019. 937 [I-D.ietf-idr-bgp-ls-segment-routing-msd] 938 Tantsura, J., Chunduri, U., Mirsky, G., Sivabalan, S., and 939 N. Triantafillis, "Signaling MSD (Maximum SID Depth) using 940 Border Gateway Protocol Link-State", draft-ietf-idr-bgp- 941 ls-segment-routing-msd-04 (work in progress), February 942 2019. 944 [I-D.ietf-idr-bgpls-segment-routing-epe] 945 Previdi, S., Talaulikar, K., Filsfils, C., Patel, K., Ray, 946 S., and J. Dong, "BGP-LS extensions for Segment Routing 947 BGP Egress Peer Engineering", draft-ietf-idr-bgpls- 948 segment-routing-epe-19 (work in progress), May 2019. 950 [I-D.li-ospf-ospfv3-srv6-extensions] 951 Li, Z., Hu, Z., Cheng, D., Talaulikar, K., and P. Psenak, 952 "OSPFv3 Extensions for SRv6", draft-li-ospf- 953 ospfv3-srv6-extensions-03 (work in progress), March 2019. 955 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 956 Requirement Levels", BCP 14, RFC 2119, 957 DOI 10.17487/RFC2119, March 1997, 958 . 960 [RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and 961 S. Ray, "North-Bound Distribution of Link-State and 962 Traffic Engineering (TE) Information Using BGP", RFC 7752, 963 DOI 10.17487/RFC7752, March 2016, 964 . 966 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 967 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 968 May 2017, . 970 [RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L., 971 Decraene, B., Litkowski, S., and R. Shakir, "Segment 972 Routing Architecture", RFC 8402, DOI 10.17487/RFC8402, 973 July 2018, . 975 14.2. Informative References 977 [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A 978 Border Gateway Protocol 4 (BGP-4)", RFC 4271, 979 DOI 10.17487/RFC4271, January 2006, 980 . 982 [RFC4272] Murphy, S., "BGP Security Vulnerabilities Analysis", 983 RFC 4272, DOI 10.17487/RFC4272, January 2006, 984 . 986 [RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter, 987 "Multiprotocol Extensions for BGP-4", RFC 4760, 988 DOI 10.17487/RFC4760, January 2007, 989 . 991 [RFC5706] Harrington, D., "Guidelines for Considering Operations and 992 Management of New Protocols and Protocol Extensions", 993 RFC 5706, DOI 10.17487/RFC5706, November 2009, 994 . 996 [RFC6952] Jethanandani, M., Patel, K., and L. Zheng, "Analysis of 997 BGP, LDP, PCEP, and MSDP Issues According to the Keying 998 and Authentication for Routing Protocols (KARP) Design 999 Guide", RFC 6952, DOI 10.17487/RFC6952, May 2013, 1000 . 1002 [RFC8355] Filsfils, C., Ed., Previdi, S., Ed., Decraene, B., and R. 1003 Shakir, "Resiliency Use Cases in Source Packet Routing in 1004 Networking (SPRING) Networks", RFC 8355, 1005 DOI 10.17487/RFC8355, March 2018, 1006 . 1008 Authors' Addresses 1009 Gaurav Dawra (editor) 1010 LinkedIn 1011 USA 1013 Email: gdawra.ietf@gmail.com 1015 Clarence Filsfils 1016 Cisco Systems 1017 Belgium 1019 Email: cfilsfil@cisco.com 1021 Ketan Talaulikar (editor) 1022 Cisco Systems 1023 India 1025 Email: ketant@cisco.com 1027 Mach Chen 1028 Huawei 1029 China 1031 Email: mach.chen@huawei.com 1033 Daniel Bernier 1034 Bell Canada 1035 Canada 1037 Email: daniel.bernier@bell.ca 1039 Bruno Decraene 1040 Orange 1041 France 1043 Email: bruno.decraene@orange.com