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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Inter-Domain Routing G. Dawra 3 Internet-Draft LinkedIn 4 Intended status: Standards Track C. Filsfils 5 Expires: January 11, 2021 K. Talaulikar, Ed. 6 Cisco Systems 7 M. Chen 8 Huawei 9 D. Bernier 10 Bell Canada 11 B. Decraene 12 Orange 13 July 10, 2020 15 BGP Link State Extensions for SRv6 16 draft-ietf-idr-bgpls-srv6-ext-03 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 behaviors 29 and other attributes via BGP. 31 Status of This Memo 33 This Internet-Draft is submitted in full conformance with the 34 provisions of BCP 78 and BCP 79. 36 Internet-Drafts are working documents of the Internet Engineering 37 Task Force (IETF). Note that other groups may also distribute 38 working documents as Internet-Drafts. The list of current Internet- 39 Drafts is at https://datatracker.ietf.org/drafts/current/. 41 Internet-Drafts are draft documents valid for a maximum of six months 42 and may be updated, replaced, or obsoleted by other documents at any 43 time. It is inappropriate to use Internet-Drafts as reference 44 material or to cite them other than as "work in progress." 46 This Internet-Draft will expire on January 11, 2021. 48 Copyright Notice 50 Copyright (c) 2020 IETF Trust and the persons identified as the 51 document authors. All rights reserved. 53 This document is subject to BCP 78 and the IETF Trust's Legal 54 Provisions Relating to IETF Documents 55 (https://trustee.ietf.org/license-info) in effect on the date of 56 publication of this document. Please review these documents 57 carefully, as they describe your rights and restrictions with respect 58 to this document. Code Components extracted from this document must 59 include Simplified BSD License text as described in Section 4.e of 60 the Trust Legal Provisions and are provided without warranty as 61 described in the Simplified BSD License. 63 Table of Contents 65 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 66 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 67 2. BGP-LS Extensions for SRv6 . . . . . . . . . . . . . . . . . 4 68 3. SRv6 Node Attributes . . . . . . . . . . . . . . . . . . . . 5 69 3.1. SRv6 Capabilities TLV . . . . . . . . . . . . . . . . . . 5 70 3.2. SRv6 Node MSD Types . . . . . . . . . . . . . . . . . . . 6 71 4. SRv6 Link Attributes . . . . . . . . . . . . . . . . . . . . 7 72 4.1. SRv6 End.X SID TLV . . . . . . . . . . . . . . . . . . . 7 73 4.2. SRv6 LAN End.X SID TLV . . . . . . . . . . . . . . . . . 9 74 4.3. SRv6 Link MSD Types . . . . . . . . . . . . . . . . . . . 11 75 5. SRv6 Prefix Attributes . . . . . . . . . . . . . . . . . . . 11 76 5.1. SRv6 Locator TLV . . . . . . . . . . . . . . . . . . . . 11 77 6. SRv6 SID NLRI . . . . . . . . . . . . . . . . . . . . . . . . 13 78 6.1. SRv6 SID Information TLV . . . . . . . . . . . . . . . . 14 79 7. SRv6 SID Attributes . . . . . . . . . . . . . . . . . . . . . 15 80 7.1. SRv6 Endpoint Behavior TLV . . . . . . . . . . . . . . . 15 81 7.2. SRv6 BGP Peer Node SID TLV . . . . . . . . . . . . . . . 16 82 7.3. SRv6 SID Structure TLV . . . . . . . . . . . . . . . . . 18 83 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19 84 8.1. BGP-LS NLRI-Types . . . . . . . . . . . . . . . . . . . . 19 85 8.2. BGP-LS TLVs . . . . . . . . . . . . . . . . . . . . . . . 19 86 9. Manageability Considerations . . . . . . . . . . . . . . . . 19 87 10. Operational Considerations . . . . . . . . . . . . . . . . . 20 88 10.1. Operations . . . . . . . . . . . . . . . . . . . . . . . 20 89 11. Security Considerations . . . . . . . . . . . . . . . . . . . 20 90 12. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 20 91 13. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 20 92 14. References . . . . . . . . . . . . . . . . . . . . . . . . . 21 93 14.1. Normative References . . . . . . . . . . . . . . . . . . 21 94 14.2. Informative References . . . . . . . . . . . . . . . . . 22 95 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 23 97 1. Introduction 99 SRv6 refers to Segment Routing instantiated on the IPv6 dataplane 100 [RFC8402]. Segment Identifier (SID) is often used as a shorter 101 reference for "SRv6 Segment". 103 The network programming paradigm 104 [I-D.ietf-spring-srv6-network-programming] is central to SRv6. It 105 describes how different behaviors can be bound to SIDs and how a 106 network program can be expressed as a combination of SIDs. 108 An SRv6-capable node N maintains all the SRv6 segments explicitly 109 instantiated at node N. 111 The IS-IS [I-D.ietf-lsr-isis-srv6-extensions] and OSPFv3 112 [I-D.ietf-lsr-ospfv3-srv6-extensions] link-state routing protocols 113 have been extended to advertise some of these SRv6 SIDs and 114 SRv6-related information. BGP ([I-D.ietf-bess-srv6-services]) has 115 been extended to advertise some of these SRv6 SIDs for VPN services. 116 Certain other SRv6 SIDs may be instantiated on a node via other 117 mechanisms for topological or service functionalities. 119 The advertisement of SR related information along with the topology 120 for the MPLS dataplane instantiation is specified in 121 [I-D.ietf-idr-bgp-ls-segment-routing-ext] and for the BGP Egress Peer 122 Engineering (EPE) is specified in 123 [I-D.ietf-idr-bgpls-segment-routing-epe]. On the similar lines, 124 introducing the SRv6 related information in BGP-LS allows consumer 125 applications that require topological visibility to also receive the 126 SRv6 SIDs from nodes across a domain or even across Autonomous 127 Systems (AS), as required. This allows applications to leverage the 128 SRv6 capabilities for network programming. 130 The identifying key of each Link-State object, namely a node, link, 131 or prefix, is encoded in the NLRI and the properties of the object 132 are encoded in the BGP-LS Attribute [RFC7752]. 134 This document describes extensions to BGP-LS to advertise the SRv6 135 SIDs and other SRv6 information from all the SRv6 capable nodes in 136 the domain when sourced from link-state routing protocols and 137 directly from individual SRv6 capable nodes when sourced from BGP. 139 1.1. Requirements Language 141 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 142 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 143 "OPTIONAL" in this document are to be interpreted as described in BCP 144 14 [RFC2119] [RFC8174] when, and only when, they appear in all 145 capitals, as shown here. 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 SRv6 Capabilities 158 TLV 160 o MSD types introduced for SRv6 are advertised as sub-TLVs of the 161 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 SR Algorithm TLV 165 specified in [I-D.ietf-idr-bgp-ls-segment-routing-ext]. 167 The SRv6 information pertaining to a link is advertised via the BGP- 168 LS Link NLRI and using the BGP-LS Attribute TLVs as follows: 170 o SRv6 End.X SID of the link state routing adjacency or the BGP EPE 171 Peer Adjacency is advertised via SRv6 End.X SID TLV introduced in 172 this document 174 o SRv6 LAN End.X SID of the link state routing adjacency to a non- 175 DR/DIS router is advertised via SRv6 LAN End.X SID TLV introduced 176 in this document 178 o MSD types introduced for SRv6 are advertised as sub-TLVs of the 179 Link MSD TLV specified in 180 [I-D.ietf-idr-bgp-ls-segment-routing-msd]. 182 The SRv6 information pertaining to a prefix is advertised via the 183 BGP-LS Prefix NLRI and using the BGP-LS Attribute TLVs as follows: 185 o SRv6 Locator is advertised via SRv6 Locator TLV introduced in this 186 document 188 o The attributes of the SRv6 Locator are advertised via the Prefix 189 Attribute Flags TLV specified in 190 [I-D.ietf-idr-bgp-ls-segment-routing-ext]. 192 The SRv6 SIDs associated with the node are advertised as a BGP-LS 193 SRv6 SID NLRI introduced in this document. This enables the BGP-LS 194 encoding to scale to cover a potentially large set of SRv6 SIDs 195 instantiated on a node with the granularity of individual SIDs and 196 without affecting the size and scalability of the BGP-LS updates. 197 BGP-LS Attribute TLVs for the SRv6 SID NLRI are introduced in this 198 document as follows: 200 o The endpoint behavior of the SRv6 SID is advertised via SRv6 201 Endpoint Behavior TLV 203 o The BGP EPE Peer Node and Peer Set SID context is advertised via 204 SRv6 BGP EPE Peer Node SID TLV 206 When the BGP-LS router is advertising topology information that it 207 sources from the underlying link-state routing protocol, then it maps 208 the corresponding SRv6 information from the SRv6 extensions for IS-IS 209 [I-D.ietf-lsr-isis-srv6-extensions] and OSPFv3 210 [I-D.ietf-lsr-ospfv3-srv6-extensions] protocols to their BGP-LS TLVs/ 211 sub-TLVs for all SRv6 capable nodes in that routing protocol domain. 212 When the BGP-LS router is advertising topology information from the 213 BGP routing protocol [I-D.ietf-idr-bgpls-segment-routing-epe], then 214 it advertises the SRv6 information from the local node alone (e.g. 215 BGP EPE topology information or in the case of a data center network 216 running BGP as the only routing protocol). 218 Subsequent sections of this document specify the encoding and usage 219 of these extensions. 221 3. SRv6 Node Attributes 223 SRv6 attributes of a node are advertised using the BGP-LS Attribute 224 TLVs defined in this section and associated with the BGP-LS Node 225 NLRI. 227 3.1. SRv6 Capabilities TLV 229 This BGP-LS Attribute TLV is used to announce the SRv6 capabilities 230 of the node along with the BGP-LS Node NLRI and indicates the SRv6 231 support by the node. A single instance of this TLV MUST be included 232 in the BGP-LS attribute for each SRv6 capable node. This TLV maps to 233 the SRv6 Capabilities sub-TLV and the SRv6 Capabilities TLV of the 234 IS-IS and OSPFv3 protocol SRv6 extensions respectively. 236 0 1 2 3 237 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 1 238 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 239 | Type | Length | 240 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 241 | Flags | Reserved | 242 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 244 Figure 1: SRv6 Capabilities TLV Format 246 Where: 248 o Type: 2 octet field with value 1038 250 o Length : 2 octet field with value set to 4. 252 o Flags: 2 octet field. The following flags are defined: 254 0 1 255 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 256 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 257 | |O| | 258 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 260 Figure 2: SRv6 Capability TLV Flags Format 262 * O-flag: If set, then router is capable of supporting SRH O-bit 263 Flags, as specified in [I-D.ietf-6man-spring-srv6-oam]. 265 o Reserved: 2 octet that SHOULD be set to 0 and MUST be ignored on 266 receipt. 268 3.2. SRv6 Node MSD Types 270 The Node MSD TLV [I-D.ietf-idr-bgp-ls-segment-routing-msd] of the 271 BGP-LS Attribute of the Node NLRI is also used to advertise the 272 limits and the supported Segment Routing Header (SRH) [RFC8754] 273 operations supported by the SRv6 capable node. The SRv6 MSD Types 274 specified in section 4 of [I-D.ietf-lsr-isis-srv6-extensions] are 275 also used with the BGP-LS Node MSD TLV as these codepoints are shared 276 between IS-IS, OSPF and BGP-LS protocols. The description and 277 semantics of these new MSD types for BGP-LS are identical as 278 specified [I-D.ietf-lsr-isis-srv6-extensions]. 280 Each MSD type is encoded as a one octet type followed by a one octet 281 value. 283 4. SRv6 Link Attributes 285 SRv6 attributes and SIDs associated with a link or adjacency are 286 advertised using the BGP-LS Attribute TLVs defined in this section 287 and associated with the BGP-LS Link NLRI. 289 4.1. SRv6 End.X SID TLV 291 The SRv6 End.X SID TLV is used to advertise the SRv6 End.X SIDs that 292 correspond to a point-to-point or point-to-multipoint link or 293 adjacency of the local node for IS-IS and OSPFv3 protocols. This TLV 294 can also be used to advertise the End.X SRv6 SID corresponding to the 295 underlying layer-2 member links for a layer-3 bundle interface using 296 L2 Bundle Member Attribute TLV as specified in 297 [I-D.ietf-idr-bgp-ls-segment-routing-ext] . 299 For the nodes running BGP routing protocol, this TLV is used to 300 advertise the BGP EPE Peer Adjacency SID for SRv6 on the same lines 301 as specified for SR/MPLS in [I-D.ietf-idr-bgpls-segment-routing-epe]. 302 The SRv6 End.X SID for the BGP Peer Adjacency indicates the cross- 303 connect to a specific layer-3 link to the specific BGP session peer 304 (neighbor). 306 The TLV has the following format: 308 0 1 2 3 309 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 1 310 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 311 | Type | Length | 312 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 313 | Endpoint Behavior | Flags | Algorithm | 314 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 315 | Weight | Reserved | SID (16 octets) ... 316 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 317 SID (cont ...) 318 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 319 SID (cont ...) 320 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 321 SID (cont ...) 322 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 323 SID (cont ...) | Sub-TLVs (variable) . . . 324 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 326 Figure 3: SRv6 End.X TLV Format 328 Where: 330 Type: 2 octet field with value 1106 332 Length: 2 octet field with the total length of the value portion 333 of the TLV. 335 Endpoint Behavior: 2 octet field. The Endpoint Behavior code 336 point for this SRv6 SID as defined in section 9.2 of 337 [I-D.ietf-spring-srv6-network-programming]. 339 Flags: 1 octet of flags with the following definition: 341 0 1 2 3 4 5 6 7 342 +-+-+-+-+-+-+-+-+ 343 |B|S|P| Rsvd | 344 +-+-+-+-+-+-+-+-+ 346 Figure 4: SRv6 End.X SID TLV Flags Format 348 * B-Flag: Backup Flag. If set, the SID is eligible for 349 protection (e.g. using IPFRR) as described in [RFC8355]. 351 * S-Flag: Set Flag. When set, the S-Flag indicates that the SID 352 refers to a set of adjacencies (and therefore MAY be assigned 353 to other adjacencies as well). 355 * P-Flag: Persistent Flag: When set, the P-Flag indicates that 356 the SID is persistently allocated, i.e., the value remains 357 consistent across router restart and/or interface flap. 359 * Rsvd bits: Reserved for future use and MUST be zero when 360 originated and ignored when received. 362 Algorithm: 1 octet field. Algorithm associated with the SID. 363 Algorithm values are defined in the IGP Algorithm Type registry. 365 Weight: 1 octet field. The value represents the weight of the SID 366 for the purpose of load balancing. The use of the weight is 367 defined in [RFC8402]. 369 Reserved: 1 octet field that SHOULD be set to 0 and MUST be 370 ignored on receipt. 372 SID: 16 octet field. This field encodes the advertised SRv6 SID 373 as 128 bit value. 375 Sub-TLVs : Used to advertise sub-TLVs that provide additional 376 attributes for the given SRv6 End.X SID. 378 4.2. SRv6 LAN End.X SID TLV 380 For a LAN interface, normally a node only announces its adjacency to 381 the IS-IS pseudo-node (or the equivalent OSPF Designated Router). 382 The SRv6 LAN End.X SID TLV allows a node to announce SRv6 SID 383 corresponding to behaviors like END.X for its adjacencies to all 384 other (i.e. non-DIS or non-DR) nodes attached to the LAN in a single 385 instance of the BGP-LS Link NLRI. Without this TLV, the 386 corresponding BGP-LS link NLRI would need to be originated for each 387 additional adjacency in order to advertise the SRv6 End.X SID TLVs 388 for these neighbor adjacencies. 390 The IS-IS and OSPFv3 SRv6 LAN End.X SID TLVs have the following 391 format: 393 0 1 2 3 394 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 1 395 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 396 | Type | Length | 397 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 398 | Endpoint Behavior | Flags | Algorithm | 399 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 400 | Weight | Reserved | ISIS System-ID (6 octets) | 401 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 402 | or OSPFv3 Router-ID (4 octets) of the neighbor | 403 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 404 | SID (16 octets) ... 405 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 406 SID (cont ...) 407 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 408 SID (cont ...) 409 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 410 SID (cont ...) | 411 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 412 | Sub-TLVs (variable) . . . 413 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 415 Figure 5: SRv6 LAN End.X SID TLV Format 417 Where: 419 o Type: 2 octet field with value 1107 in case of IS-IS and 1108 in 420 case of OSPFv3 422 o Length: 2 octet field with the total length of the value portion 423 of the TLV. 425 o Endpoint Behavior: 2 octet field. The Endpoint Behavior code 426 point for this SRv6 SID as defined in section 9.2 of 427 [I-D.ietf-spring-srv6-network-programming]. 429 o Flags: 1 octet of flags with the following definition: 431 0 1 2 3 4 5 6 7 432 +-+-+-+-+-+-+-+-+ 433 |B|S|P| Rsvd | 434 +-+-+-+-+-+-+-+-+ 436 Figure 6: SRv6 LAN End.X SID TLV Flags Format 438 * B-Flag: Backup Flag. If set, the SID is eligible for 439 protection (e.g. using IPFRR) as described in [RFC8355]. 441 * S-Flag: Set Flag. When set, the S-Flag indicates that the SID 442 refers to a set of adjacencies (and therefore MAY be assigned 443 to other adjacencies as well). 445 * P-Flag: Persistent Flag: When set, the P-Flag indicates that 446 the SID is persistently allocated, i.e., the value remains 447 consistent across router restart and/or interface flap. 449 * Rsvd bits: Reserved for future use and MUST be zero when 450 originated and ignored when received. 452 o Algorithm: 1 octet field. Algorithm associated with the SID. 453 Algorithm values are defined in the IGP Algorithm Type registry. 455 o Weight: 1 octet field. The value represents the weight of the SID 456 for the purpose of load balancing. The use of the weight is 457 defined in [RFC8402]. 459 o Reserved: 1 octet field that SHOULD be set to 0 and MUST be 460 ignored on receipt. 462 o Neighbor ID : 6 octets of ISIS System ID of the neighbor for the 463 ISIS SRv6 LAN End.X SID TLV and 4 octets of OSPFv3 Router-id of 464 the neighbor for the OSPFv3 SRv6 LAN End.X SID TLV. 466 o SID: 16 octet field. This field encodes the advertised SRv6 SID 467 as 128 bit value. 469 o Sub-TLVs : Used to advertise sub-TLVs that provide additional 470 attributes for the given SRv6 LAN End.X SID. 472 4.3. SRv6 Link MSD Types 474 The Link MSD TLV [I-D.ietf-idr-bgp-ls-segment-routing-msd] of the 475 BGP-LS Attribute of the Link NLRI is also used to advertise the 476 limits and the supported Segment Routing Header (SRH) operations 477 supported on the specific link by the SRv6 capable node. The SRv6 478 MSD Types specified in section 4 479 of[I-D.ietf-lsr-isis-srv6-extensions] are also used with the BGP-LS 480 Link MSD TLV as these codepoints are shared between IS-IS, OSPF and 481 BGP-LS protocols. The description and semantics of these new MSD 482 types for BGP-LS are identical as specified 483 [I-D.ietf-lsr-isis-srv6-extensions]. 485 Each MSD type is encoded as a one octet type followed by a one octet 486 value. 488 5. SRv6 Prefix Attributes 490 SRv6 attributes with an IPv6 prefix are advertised using the new BGP- 491 LS Attribute TLVs defined in this section and associated with the 492 BGP-LS Prefix NLRI. 494 5.1. SRv6 Locator TLV 496 As described in [I-D.ietf-spring-srv6-network-programming], an SRv6 497 SID is 128 bits and comprises of Locator, Function and Argument 498 parts. 500 A node is provisioned with one or more locators supported by that 501 node. Locators are covering prefixes for the set of SIDs provisioned 502 on that node. These Locators are advertised as BGP-LS Prefix NLRI 503 objects along with the SRv6 Locator TLV in its BGP-LS Attribute. 505 The IPv6 Prefix matching the Locator MAY be also advertised as a 506 prefix reachability by the underlying routing protocol. In this 507 case, the Prefix NLRI would be also associated with the Prefix Metric 508 TLV that carries the routing metric for this prefix. When the 509 Locator prefix is not being advertised as a prefix reachability, then 510 the Prefix NLRI would have the SRv6 Locator TLV associated with it 511 but no Prefix Metric TLV. In the absence of Prefix Metric TLV, the 512 consumer of the BGP-LS topology information MUST NOT interpret the 513 Locator prefix as a prefix reachability routing advertisement. 515 The SRv6 Locator TLV has the following format: 517 0 1 2 3 518 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 1 519 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 520 | Type | Length | 521 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 522 | Flags | Algorithm | Reserved | 523 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 524 | Metric | 525 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 526 | Sub-TLVs (variable) . . . 527 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 529 Figure 7: SRv6 Locator TLV Format 531 Where: 533 Type: 2 octet field with value 1162 535 Length: 2 octet field with the total length of the value portion 536 of the TLV. 538 Flags: 1 octet of flags with the following definition: 540 0 1 2 3 4 5 6 7 541 +-+-+-+-+-+-+-+-+ 542 |D| Reserved | 543 +-+-+-+-+-+-+-+-+ 545 Figure 8: SRv6 Locator TLV Flags Format 547 * D-Flag: Indicates that the locator has been leaked into the IGP 548 domain when set. IS-IS operations for this are discussed in 549 [I-D.ietf-lsr-isis-srv6-extensions]. 551 * Reserved bits: Reserved for future use and MUST be zero when 552 originated and ignored when received. 554 Algorithm: 1 octet field. Algorithm associated with the SID. 555 Algorithm values are defined in the IGP Algorithm Type registry. 557 Reserved: 2 octet field. The value MUST be zero when originated 558 and ignored when received. 560 Metric: 4 octet field. The value of the metric for the Locator. 562 Sub-TLVs : currently none defined. Used to advertise sub-TLVs 563 that provide additional attributes for the given SRv6 Locator. 565 6. SRv6 SID NLRI 567 SRv6 SID information is advertised in BGP UPDATE messages using the 568 MP_REACH_NLRI and MP_UNREACH_NLRI attributes [RFC4760]. The "Link- 569 State NLRI" defined in [RFC7752] is extended to carry the SRv6 SID 570 information. 572 A new "Link-State NLRI Type" is defined for SRv6 SID information as 573 following: 575 o Link-State NLRI Type: SRv6 SID NLRI value 6. 577 The format of this new NLRI type is as shown in the following figure: 579 0 1 2 3 580 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 1 581 +-+-+-+-+-+-+-+-+ 582 | Protocol-ID | 583 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 584 | Identifier | 585 | (64 bits) | 586 ++-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+| 587 | Local Node Descriptors (variable) // 588 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 589 | SRv6 SID Descriptors (variable) // 590 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 592 Figure 9: SRv6 SID NLRI Format 594 Where: 596 o Protocol-ID: 1 octet field that specifies the protocol component 597 through which BGP-LS learns the SRv6 SIDs of the node. The 598 following Protocol-IDs apply to the SRv6 SID NLRI: 600 +-------------+----------------------------------+ 601 | Protocol-ID | NLRI information source protocol | 602 +-------------+----------------------------------+ 603 | 1 | IS-IS Level 1 | 604 | 2 | IS-IS Level 2 | 605 | 4 | Direct | 606 | 5 | Static configuration | 607 | 6 | OSPFv3 | 608 | 7 | BGP | 609 +-------------+----------------------------------+ 611 Figure 10: Protocol IDs for SRv6 SID NLRI 613 o Identifier: 8 octet value as defined in [RFC7752]. 615 o Local Node Descriptors TLV: as defined in [RFC7752] for IGPs, 616 local and static configuration and as defined in 617 [I-D.ietf-idr-bgpls-segment-routing-epe] for BGP protocol. 619 o SRv6 SID Descriptors: MUST include the SRv6 SID Information TLV 620 defined in Section 6.1 and optionally MAY include the Multi- 621 Topology Identifier TLV as defined in [RFC7752]. 623 New TLVs carried in the BGP Link State Attribute defined in [RFC7752] 624 are also defined in order to carry the attributes of a SRv6 SID in 625 Section 7. 627 6.1. SRv6 SID Information TLV 629 A SRv6 SID is a 128 bit value 630 [I-D.ietf-spring-srv6-network-programming] and is encoded using the 631 SRv6 SID Information TLV. 633 The TLV has the following format: 635 0 1 2 3 636 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 1 637 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 638 | Type | Length | 639 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 640 | SID (16 octets) ... 641 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 642 SID (cont ...) 643 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 644 SID (cont ...) 645 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 646 SID (cont ...) | 647 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 649 Figure 11: SRv6 SID Information TLV Format 651 Where: 653 Type: 2 octet field with value 518 655 Length: 2 octet field with value set to 16. 657 SID: 16 octet field. This field encodes the advertised SRv6 SID 658 as 128 bit value. 660 7. SRv6 SID Attributes 662 This section specifies the new TLVs to be carried in the BGP Link 663 State Attribute associated with the BGP-LS SRv6 SID NLRI. 665 7.1. SRv6 Endpoint Behavior TLV 667 Each SRv6 SID instantiated on an SRv6 capable node has a specific 668 instruction bound to it. A set of well-known behaviors that can be 669 associated with a SID are defined in 670 [I-D.ietf-spring-srv6-network-programming]. 672 The SRv6 Endpoint Behavior TLV is a mandatory TLV that MUST be 673 included in the BGP-LS Attribute associated with the BGP-LS SRv6 SID 674 NLRI. The TLV has the following format: 676 0 1 2 3 677 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 1 678 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 679 | Type | Length | 680 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 681 | Endpoint Behavior | Flags | Algorithm | 682 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 684 Figure 12: SRv6 Endpoint Behavior TLV 686 Where: 688 Type: 2 octet field with value 1250 690 Length: 2 octet field with the value 4. 692 Endpoint Behavior: 2 octet field. The Endpoint Behavior code 693 point for this SRv6 SID as defined in section 9.2 of 694 [I-D.ietf-spring-srv6-network-programming]. 696 Flags: 1 octet of flags with the none defined currently. Reserved 697 for future use and MUST be zero when originated and ignored when 698 received. 700 Algorithm: 1 octet field. Algorithm associated with the SID. 701 Algorithm values are defined in the IGP Algorithm Type registry. 703 7.2. SRv6 BGP Peer Node SID TLV 705 The BGP Peer Node SID and Peer Set SID for SR with MPLS dataplane are 706 specified in [I-D.ietf-idr-bgpls-segment-routing-epe]. The similar 707 Peer Node and Peer Set functionality can be realized with SRv6 using 708 the END.X behavior. The SRv6 BGP Peer Node SID TLV is an optional 709 TLV for use in the BGP-LS Attribute for an SRv6 SID NLRI 710 corresponding to BGP protocol. This TLV MUST be included along with 711 SRv6 End.X SID that is associated with the BGP Peer Node or Peer Set 712 functionality. 714 The TLV has the following format: 716 0 1 2 3 717 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 1 718 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 719 | Type | Length | 720 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 721 | Flags | Weight | Reserved | 722 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 723 | Peer AS Number | 724 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 725 | Peer BGP Identifier | 726 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 728 Figure 13: SRv6 BGP Peer Node SID TLV Format 730 Where: 732 o Type: 2 octet field with value 1251 734 o Length: 2 octet field with the value 12. 736 o Flags: 1 octet of flags with the following definition: 738 0 1 2 3 4 5 6 7 739 +-+-+-+-+-+-+-+-+ 740 |B|S|P| Rsvd | 741 +-+-+-+-+-+-+-+-+ 743 Figure 14: SRv6 BGP Peer End.X SID TLV Flags Format 745 * B-Flag: Backup Flag. If set, the SID is eligible for 746 protection (e.g. using IPFRR) as described in [RFC8355]. 748 * S-Flag: Set Flag. When set, the S-Flag indicates that the SID 749 refers to a set of BGP peering sessions (i.e. BGP Peer Set SID 750 functionality) and therefore MAY be assigned to one or more 751 End.X SIDs associated with BGP peer sessions. 753 * P-Flag: Persistent Flag: When set, the P-Flag indicates that 754 the SID is persistently allocated, i.e., the value remains 755 consistent across router restart and/or session flap. 757 * Rsvd bits: Reserved for future use and MUST be zero when 758 originated and ignored when received. 760 o Weight: 1 octet field. The value represents the weight of the SID 761 for the purpose of load balancing. The use of the weight is 762 defined in [RFC8402]. 764 o Peer AS Number : 4 octets of BGP AS number of the peer router. 766 o Peer BGP Identifier : 4 octets of the BGP Identifier (BGP Router- 767 ID) of the peer router. 769 For a SRv6 BGP EPE Peer Node SID, one instance of this TLV is 770 associated with the SRv6 SID. For SRv6 BGP EPE Peer Set SID, 771 multiple instances of this TLV (one for each peer in the "peer set") 772 are associated with the SRv6 SID and the S (set/group) flag is SET. 774 7.3. SRv6 SID Structure TLV 776 SRv6 SID Structure TLV is used to advertise the length of each 777 individual part of the SRv6 SID as defined in 778 [I-D.ietf-spring-srv6-network-programming]. It is an optional TLV 779 for use in the BGP-LS Attribute for an SRv6 SID NLRI and as an 780 optional sub-TLV of the SRv6 End, IS-IS SRv6 LAN End.X and OSPFv3 781 SRv6 LAN End.X TLVs. The TLV has the following format: 783 0 1 2 3 784 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 1 785 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 786 | Type | Length | 787 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 788 | LB Length | LN Length | Fun. Length | Arg. Length | 789 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 791 Figure 15: SRv6 SID Structure TLV 793 Where: 795 Type: 2 octet field with value 1252 797 Length: 2 octet field with the value 4. 799 LB Length: 1 octet field. SRv6 SID Locator Block length in bits. 801 LN Length: 1 octet field. SRv6 SID Locator Node length in bits. 803 Function Length: 1 octet field. SRv6 SID Function length in bits. 805 Argument Length: 1 octet field. SRv6 SID Argument length in bits. 807 8. IANA Considerations 809 This document requests assigning code-points from the IANA "Border 810 Gateway Protocol - Link State (BGP-LS) Parameters" registry as 811 described in the sub-sections below. 813 8.1. BGP-LS NLRI-Types 815 The following codepoints are assigned by IANA via the early 816 allocation processs from within the sub-registry called "BGP-LS NLRI- 817 Types": 819 +------+----------------------------+---------------+ 820 | Type | NLRI Type | Reference | 821 +------+----------------------------+---------------+ 822 | 6 | SRv6 SID | this document | 823 +------+----------------------------+---------------+ 825 Figure 16: SRv6 SID NLRI Type Codepoint 827 8.2. BGP-LS TLVs 829 The following TLV codepoints are assigned by IANA via the early 830 allocation process from within the sub-registry called "BGP-LS Node 831 Descriptor, Link Descriptor, Prefix Descriptor, and Attribute TLVs": 833 +----------+----------------------------------------+---------------+ 834 | TLV Code | Description | Value defined | 835 | Point | | in | 836 +----------+----------------------------------------+---------------+ 837 | 1038 | SRv6 Capabilities TLV | this document | 838 | 1106 | SRv6 End.X SID TLV | this document | 839 | 1107 | IS-IS SRv6 LAN End.X SID TLV | this document | 840 | 1108 | OSPFv3 SRv6 LAN End.X SID TLV | this document | 841 | 1162 | SRv6 Locator TLV | this document | 842 | 518 | SRv6 SID Information TLV | this document | 843 | 1250 | SRv6 Endpoint Behavior TLV | this document | 844 | 1251 | SRv6 BGP Peer Node SID TLV | this document | 845 | 1252 | SRv6 SID Structure TLV | this document | 846 +----------+----------------------------------------+---------------+ 848 Figure 17: SRv6 BGP-LS Attribute TLV Codepoints 850 9. Manageability Considerations 852 This section is structured as recommended in[RFC5706] 854 10. Operational Considerations 856 10.1. Operations 858 Existing BGP and BGP-LS operational procedures apply. No additional 859 operation procedures are defined in this document. 861 11. Security Considerations 863 Procedures and protocol extensions defined in this document do not 864 affect the BGP security model. See the 'Security Considerations' 865 section of [RFC4271] for a discussion of BGP security. Also refer 866 to[RFC4272] and [RFC6952] for analysis of security issues for BGP. 868 12. Contributors 870 James Uttaro 871 AT&T 872 USA 873 Email: ju1738@att.com 875 Hani Elmalky 876 Ericsson 877 USA 878 Email: hani.elmalky@gmail.com 880 Arjun Sreekantiah 881 Individual 882 USA 883 Email: arjunhrs@gmail.com 885 Les Ginsberg 886 Cisco Systems 887 USA 888 Email: ginsberg@cisco.com 890 Shunwan Zhuang 891 Huawei 892 China 893 Email: zhuangshunwan@huawei.com 895 13. Acknowledgements 897 The authors would like to thank Peter Psenak, Arun Babu, Pablo 898 Camarillo and Francois Clad for their review of this document and 899 their comments. 901 14. References 903 14.1. Normative References 905 [I-D.ietf-6man-spring-srv6-oam] 906 Ali, Z., Filsfils, C., Matsushima, S., Voyer, D., and M. 907 Chen, "Operations, Administration, and Maintenance (OAM) 908 in Segment Routing Networks with IPv6 Data plane (SRv6)", 909 draft-ietf-6man-spring-srv6-oam-05 (work in progress), 910 June 2020. 912 [I-D.ietf-idr-bgp-ls-segment-routing-ext] 913 Previdi, S., Talaulikar, K., Filsfils, C., Gredler, H., 914 and M. Chen, "BGP Link-State extensions for Segment 915 Routing", draft-ietf-idr-bgp-ls-segment-routing-ext-16 916 (work in progress), June 2019. 918 [I-D.ietf-idr-bgp-ls-segment-routing-msd] 919 Tantsura, J., Chunduri, U., Talaulikar, K., Mirsky, G., 920 and N. Triantafillis, "Signaling MSD (Maximum SID Depth) 921 using Border Gateway Protocol - Link State", draft-ietf- 922 idr-bgp-ls-segment-routing-msd-18 (work in progress), May 923 2020. 925 [I-D.ietf-idr-bgpls-segment-routing-epe] 926 Previdi, S., Talaulikar, K., Filsfils, C., Patel, K., Ray, 927 S., and J. Dong, "BGP-LS extensions for Segment Routing 928 BGP Egress Peer Engineering", draft-ietf-idr-bgpls- 929 segment-routing-epe-19 (work in progress), May 2019. 931 [I-D.ietf-lsr-isis-srv6-extensions] 932 Psenak, P., Filsfils, C., Bashandy, A., Decraene, B., and 933 Z. Hu, "IS-IS Extension to Support Segment Routing over 934 IPv6 Dataplane", draft-ietf-lsr-isis-srv6-extensions-08 935 (work in progress), April 2020. 937 [I-D.ietf-lsr-ospfv3-srv6-extensions] 938 Li, Z., Hu, Z., Cheng, D., Talaulikar, K., and P. Psenak, 939 "OSPFv3 Extensions for SRv6", draft-ietf-lsr- 940 ospfv3-srv6-extensions-00 (work in progress), February 941 2020. 943 [I-D.ietf-spring-srv6-network-programming] 944 Filsfils, C., Camarillo, P., Leddy, J., Voyer, D., 945 Matsushima, S., and Z. Li, "SRv6 Network Programming", 946 draft-ietf-spring-srv6-network-programming-16 (work in 947 progress), June 2020. 949 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 950 Requirement Levels", BCP 14, RFC 2119, 951 DOI 10.17487/RFC2119, March 1997, 952 . 954 [RFC7752] Gredler, H., Ed., Medved, J., Previdi, S., Farrel, A., and 955 S. Ray, "North-Bound Distribution of Link-State and 956 Traffic Engineering (TE) Information Using BGP", RFC 7752, 957 DOI 10.17487/RFC7752, March 2016, 958 . 960 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 961 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 962 May 2017, . 964 [RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L., 965 Decraene, B., Litkowski, S., and R. Shakir, "Segment 966 Routing Architecture", RFC 8402, DOI 10.17487/RFC8402, 967 July 2018, . 969 [RFC8754] Filsfils, C., Ed., Dukes, D., Ed., Previdi, S., Leddy, J., 970 Matsushima, S., and D. Voyer, "IPv6 Segment Routing Header 971 (SRH)", RFC 8754, DOI 10.17487/RFC8754, March 2020, 972 . 974 14.2. Informative References 976 [I-D.ietf-bess-srv6-services] 977 Dawra, G., Filsfils, C., Raszuk, R., Decraene, B., Zhuang, 978 S., and J. Rabadan, "SRv6 BGP based Overlay services", 979 draft-ietf-bess-srv6-services-02 (work in progress), 980 February 2020. 982 [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A 983 Border Gateway Protocol 4 (BGP-4)", RFC 4271, 984 DOI 10.17487/RFC4271, January 2006, 985 . 987 [RFC4272] Murphy, S., "BGP Security Vulnerabilities Analysis", 988 RFC 4272, DOI 10.17487/RFC4272, January 2006, 989 . 991 [RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter, 992 "Multiprotocol Extensions for BGP-4", RFC 4760, 993 DOI 10.17487/RFC4760, January 2007, 994 . 996 [RFC5706] Harrington, D., "Guidelines for Considering Operations and 997 Management of New Protocols and Protocol Extensions", 998 RFC 5706, DOI 10.17487/RFC5706, November 2009, 999 . 1001 [RFC6952] Jethanandani, M., Patel, K., and L. Zheng, "Analysis of 1002 BGP, LDP, PCEP, and MSDP Issues According to the Keying 1003 and Authentication for Routing Protocols (KARP) Design 1004 Guide", RFC 6952, DOI 10.17487/RFC6952, May 2013, 1005 . 1007 [RFC8355] Filsfils, C., Ed., Previdi, S., Ed., Decraene, B., and R. 1008 Shakir, "Resiliency Use Cases in Source Packet Routing in 1009 Networking (SPRING) Networks", RFC 8355, 1010 DOI 10.17487/RFC8355, March 2018, 1011 . 1013 Authors' Addresses 1015 Gaurav Dawra 1016 LinkedIn 1017 USA 1019 Email: gdawra.ietf@gmail.com 1021 Clarence Filsfils 1022 Cisco Systems 1023 Belgium 1025 Email: cfilsfil@cisco.com 1027 Ketan Talaulikar (editor) 1028 Cisco Systems 1029 India 1031 Email: ketant@cisco.com 1033 Mach Chen 1034 Huawei 1035 China 1037 Email: mach.chen@huawei.com 1038 Daniel Bernier 1039 Bell Canada 1040 Canada 1042 Email: daniel.bernier@bell.ca 1044 Bruno Decraene 1045 Orange 1046 France 1048 Email: bruno.decraene@orange.com