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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Work group N. Kumar, Ed. 3 Internet-Draft C. Pignataro, Ed. 4 Intended status: Standards Track F. Iqbal 5 Expires: April 26, 2019 Z. Ali 6 Cisco 7 October 23, 2018 9 Label Switched Path (LSP) Ping/Traceroute for Segment Routing SIDs with 10 MPLS Data-plane 11 draft-nainar-mpls-spring-lsp-ping-sids-00 13 Abstract 15 RFC8402 introduces Segment Routing architecture that leverages source 16 routing and tunneling paradigms and can be directly applied to the 17 Multi Protocol Label Switching (MPLS) data plane. A node steers a 18 packet through a controlled set of instructions called segments, by 19 prepending the packet with Segment Routing header. SR architecture 20 defines different types of segments with different forwarding 21 semantics associated. 23 RFC8287 defines the extensions to MPLS LSP Ping and Traceroute for 24 Segment Routing IGP-Prefix and IGP-Adjacency Segment Identifier 25 (SIDs) with an MPLS data plane. RFC8287 defines the Target FEC Stack 26 Sub-TLVs and the procedures to apply RFC8029 on SR architecture with 27 MPLS data plane. 29 This document defines the Target FEC Stack Sub-TLVs and the extension 30 required for other SR Segments. 32 Status of This Memo 34 This Internet-Draft is submitted in full conformance with the 35 provisions of BCP 78 and BCP 79. 37 Internet-Drafts are working documents of the Internet Engineering 38 Task Force (IETF). Note that other groups may also distribute 39 working documents as Internet-Drafts. The list of current Internet- 40 Drafts is at https://datatracker.ietf.org/drafts/current/. 42 Internet-Drafts are draft documents valid for a maximum of six months 43 and may be updated, replaced, or obsoleted by other documents at any 44 time. It is inappropriate to use Internet-Drafts as reference 45 material or to cite them other than as "work in progress." 47 This Internet-Draft will expire on April 26, 2019. 49 Copyright Notice 51 Copyright (c) 2018 IETF Trust and the persons identified as the 52 document authors. All rights reserved. 54 This document is subject to BCP 78 and the IETF Trust's Legal 55 Provisions Relating to IETF Documents 56 (https://trustee.ietf.org/license-info) in effect on the date of 57 publication of this document. Please review these documents 58 carefully, as they describe your rights and restrictions with respect 59 to this document. Code Components extracted from this document must 60 include Simplified BSD License text as described in Section 4.e of 61 the Trust Legal Provisions and are provided without warranty as 62 described in the Simplified BSD License. 64 Table of Contents 66 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 67 2. Requirements notation . . . . . . . . . . . . . . . . . . . . 3 68 3. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 69 4. Segment ID sub-TLV . . . . . . . . . . . . . . . . . . . . . 4 70 4.1. BGP Prefix Segment ID . . . . . . . . . . . . . . . . . . 4 71 4.2. BGP Peering Segment - Peer-Node-SID . . . . . . . . . . . 4 72 4.3. BGP Peering Segment - Peer-Adj-SID . . . . . . . . . . . 5 73 4.4. BGP Peering Segment - Peer-Set-SID . . . . . . . . . . . 7 74 4.4.1. Peer Set Sub-TLV . . . . . . . . . . . . . . . . . . 8 75 4.5. Path Binding SID . . . . . . . . . . . . . . . . . . . . 9 76 4.6. Multicast Replication . . . . . . . . . . . . . . . . . . 10 77 5. Procedures . . . . . . . . . . . . . . . . . . . . . . . . . 10 78 5.1. BGP Prefix SID . . . . . . . . . . . . . . . . . . . . . 10 79 5.2. BGP Peering Segment Sub-TLVs . . . . . . . . . . . . . . 10 80 5.2.1. Initiator Node Procedures . . . . . . . . . . . . . . 10 81 5.2.2. Responder Node Procedures . . . . . . . . . . . . . . 11 82 5.3. Path Binding SID . . . . . . . . . . . . . . . . . . . . 11 83 5.3.1. Initiator Node Procedures . . . . . . . . . . . . . . 11 84 5.3.2. Responder Node Procedures . . . . . . . . . . . . . . 11 85 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 86 7. Security Considerations . . . . . . . . . . . . . . . . . . . 11 87 8. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 12 88 9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 12 89 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 12 90 10.1. Normative References . . . . . . . . . . . . . . . . . . 12 91 10.2. Informative References . . . . . . . . . . . . . . . . . 13 92 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14 94 1. Introduction 96 [RFC8402] introduces and describes a Segment Routing architecture 97 that leverages the source routing and tunneling paradigms. A node 98 steers a packet through a controlled set of instructions called 99 segments, by prepending the packet with Segment Routing header. A 100 detailed definition of the Segment Routing architecture is available 101 in [RFC8402] 103 As described in [RFC8402] and [I-D.ietf-spring-segment-routing-mpls], 104 the Segment Routing architecture can be directly applied to an MPLS 105 data plane, the Segment identifier (Segment ID) will be of 20-bits 106 size and the Segment Routing header is the label stack. 108 [RFC8287] defines the mechanism to perform LSP Ping and Traceroute 109 for Segment Routing with MPLS data plane. [RFC8287] defines the 110 Target FEC Stack Sub-TLVs for IGP-Prefix Segment ID and IGP-Adjacency 111 Segment ID. 113 There are various other Segment IDs proposed by different documents 114 that are applicable for SR architecture. 115 [I-D.ietf-idr-bgp-prefix-sid] defines BGP Prefix Segment ID, 116 [I-D.ietf-idr-bgpls-segment-routing-epe] defines BGP Peering Segment 117 ID such as Peer Node SID, Peer Adj SID and Peer Set SID. 118 [I-D.sivabalan-pce-binding-label-sid] defines Path Binding Segment 119 ID. 121 As above Segment IDs get deployed in the field, operators require 122 corresponding MPLS OAM procedures for the SIDs. This document 123 describes the target FEC Stack Sub-TLVs and the procedure to use LSP 124 Ping and Traceroute for the above defined Segment IDs to support path 125 validation and fault isolation. 127 2. Requirements notation 129 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 130 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 131 document are to be interpreted as described in [RFC2119]. 133 3. Terminology 135 This document uses the terminologies defined in [RFC8402], [RFC8029], 136 readers are expected to be familiar with it. 138 The term "BGP EPE node" is used to refer to node assigning and 139 advertising BGP Peering Segment SIDs to steer traffic towards a BGP 140 peer, as described in [I-D.ietf-spring-segment-routing-central-epe]. 142 4. Segment ID sub-TLV 144 As defined in Section 5 of [RFC8287], the format of the following 145 Segment ID sub-TLVs defined in this document follows the philosophy 146 of Target FEC Stack TLV carrying FECs corresponding to each label in 147 the label stack. 149 4.1. BGP Prefix Segment ID 151 Section 3.2.13 and 3.2.14 of [RFC8029] defines the Sub-TLV for BGP 152 labeled IPv4 and IPv6 prefix respectively. This document proposes 153 the use of the same Sub-TLV for IPv4 and IPv6 BGP Prefix SID without 154 any change. 156 4.2. BGP Peering Segment - Peer-Node-SID 158 Peer-Node-SID identifies the peer node in the BGP Peering Segment. 159 The sub-TLV format for Peer-Node-SID of BGP Peering Segment MUST be 160 set as shown in the below TLV format: 162 0 1 2 3 163 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 1 164 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 165 |Type = TBD1 | Length = x | 166 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 167 | AF.Type | Reserved | 168 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 169 | Local BGP Router ID (4 octets) | 170 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 171 | Local ASN (4 octets) | 172 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 173 | Peer BGP Router ID (4 octets) | 174 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 175 | Peer ASN (4 octets) | 176 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 177 | Local Interface address (4 or 16 octets) | 178 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 179 | Remote Interface address (4 or 16 octets) | 180 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 182 AF.Type 184 Set to 4 if the address in Local/Remote Interface address field is 185 IPv4 and set to 6 if the address in Local/Remote Interface address 186 field is IPv6. 188 Reserved 190 MUST be set to 0 on send and MUST be ignored on receipt. 192 Local BGP Router ID 194 4-octet BGP Router ID of the node that assigns the Peer-Node-SID. 196 Local ASN 198 4-octet local ASN number of the node that assigns the Peer-Node- 199 SID. 201 Peer BGP Router ID 203 4-octet BGP Router ID of the peer node. 205 Peer ASN 207 4-octet ASN number of the peer node. 209 Local Interface Address 211 Set to the address used by the local node for BGP session peering. 212 When AF.Type is set to 4, this address is 4-octet IPv4 address and 213 when AF.Type is set to 6, this address is 16-octet IPv6 address. 215 Remote Interface Address 217 Set to the address used by the peer node for BGP session peering. 218 When AF.Type is set to 4, this address is 4-octet IPv4 address and 219 when AF.Type is set to 6, this address is 16-octet IPv6 address. 221 4.3. BGP Peering Segment - Peer-Adj-SID 223 Peer-Adj-SID identifies the underlying link to the BGP peer node. 224 The sub-TLV format for Peer-Adj-SID of BGP Peering Segment MUST be 225 set as shown in the below TLV format: 227 0 1 2 3 228 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 1 229 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 230 | Type = TBD2 | Length = 24 | 231 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 232 | Local BGP Router ID (4 octets) | 233 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 234 | Local ASN (4 octets) | 235 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 236 | Peer BGP Router ID (4 octets) | 237 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 238 | Peer ASN (4 octets) | 239 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 240 | Local Link Identifier (4 octet) | 241 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 242 | Remote Link Identifier (4 octet) | 243 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 245 Local BGP Router ID 247 4-octet BGP Router ID of the node that assigns the Peer-Node-SID. 249 Local ASN 251 4-octet local ASN number of the node that assigns the Peer-Node- 252 SID. 254 Peer BGP Router ID 256 4-octet BGP Router ID of the peer node. 258 Peer ASN 260 4-octet ASN number of the peer node. 262 Local Link Identifier 264 Set to 4-octet link identifier of the local interface to which 265 Peer-Adj-SID is assigned to. 267 Remote Link Identifier 269 Set to 4-octet link identifier of the peer interface to which 270 Peer-Adj-SID is assigned to. Set to all-zeros when this 271 identifier is unknown. 273 4.4. BGP Peering Segment - Peer-Set-SID 275 The sub-TLV format for Peer-Node-SID of BGP Peering Segment MUST be 276 set as shown in the below TLV format: 278 0 1 2 3 279 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 1 280 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 281 |Type = TBD3 | Length = x | 282 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 283 | Local BGP Router ID (4 octets) | 284 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 285 | Local ASN (4 octets) | 286 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 287 | Peer Set Count | Reserved | 288 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 289 . . 290 . List of Peer Set Sub-TLVs . 291 . . 292 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 294 Local BGP Router ID 296 4-octet BGP Router ID of the node that assigns the Peer-Set-SID. 298 Local ASN 300 4-octet local ASN number of the node that assigns the Peer-Set- 301 SID. 303 Peer Set Count 305 Set to the number of Peer Sub-TLVs included. 307 Sub-TLV Length 309 Total length in octets of the sub-TLVs associated with this TLV. 311 Peer Set Sub-TLV 313 Carries the Sub-TLVs defined in section 4.4.1. 315 4.4.1. Peer Set Sub-TLV 317 As defined in section 5.3 of 318 [I-D.ietf-idr-bgpls-segment-routing-epe], Peer-Set-SID can identify 319 the set where the members can be Peer-Node or Peer-Adj from same or 320 different ASN. The format of the Peer Set Sub-TLV will identify each 321 such member. 323 4.4.1.1. Peer Node 325 The format for this sub-TLV MUST be set as below: 327 0 1 2 3 328 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 1 329 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 330 | Type = 1 (Peer) | Length = 8 | 331 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 332 | Peer ASN (4 octets) | 333 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 334 | Peer BGP Router ID (4 octets) | 335 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 337 Peer ASN 339 4-octet ASN number of the peer node. 341 Peer Router ID 343 4-octet BGP Router ID of the peer node. 345 4.4.1.2. Link Identifier 347 The format for this sub-TLV is as below: 349 0 1 2 3 350 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 1 351 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 352 | Type = 2 (Link Id) | Length = 12 | 353 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 354 | Peer ASN (4 octets) | 355 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 356 | Local Link Identifier (4 octet) | 357 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 358 | Remote Link Identifier (4 octet) | 359 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 361 Peer ASN 363 4-octet ASN number of the peer node. 365 Local Link Identifier 367 Set to 4-octet link identifier of the local interface to which 368 Peer-Adj-SID is assigned to. 370 Remote Link Identifier 372 Set to 4-octet link identifier of the peer interface to which 373 Peer-Adj-SID is assigned to. Set to all-zeros when this 374 identifier is unknown. 376 4.5. Path Binding SID 378 Path Binding SID identifies the Binding Segment Identifier associated 379 with an RSVP-TE or SR-TE path. The format for this sub-TLV is as 380 below: 382 0 1 2 3 383 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 1 384 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 385 |Type = TBD4 | Length = x | 386 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 387 | AF.Type | Reserved | 388 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 389 | Head End Address (4 or 16 octets) | 390 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 392 AF.Type 393 Set to 4 if the address in Head End Address field is IPv4 and set 394 to 6 if the address in Head End address field is IPv6. 396 Reserved 398 MUST be set to 0 on send and MUST be ignored on receipt. 400 Head End Address 402 Set to the address of the head end node to which the policy is 403 assigned. When AF.Type is 4, this address is IPv4 and when 404 AF.Type is 6, it is IPv6. 406 4.6. Multicast Replication 408 [I-D.voyer-spring-sr-p2mp-policy] describes Segment Routing Multicast 409 Replication Policy and introduces the notion of Tree SID to achieve 410 this. A future version of this document will describe LSP Ping and 411 Traceroute Target FEC Stack sub-TLV and procedures for Tree SID 412 validation. 414 5. Procedures 416 This section describes the aspects of LSP Ping and Traceroute 417 operations that require further considerations beyond [RFC8029] and 418 [RFC8287]. 420 5.1. BGP Prefix SID 422 The procedures described in [RFC8029] are sufficient for MPLS Ping 423 and Traceroute operations for BGP Prefix SID using the FEC 424 definitions from Section 3.2.13 and 3.2.14 of [RFC8029]. 426 5.2. BGP Peering Segment Sub-TLVs 428 BGP Peering Segment sub-TLVs (BGP-Node-SID, BGP-Adj-SID, Peer-Set- 429 SID) are assigned by BGP EPE node for a particular BGP neighbor, and 430 advertised to the peer nodes. Any LSP Ping and Traceroute operation 431 MUST be performed on the BGP EPE node, and not the remote neighbor 432 node, as only the BGP EPE node can validate the contents of BGP 433 Peering Segment sub-TLVs. Additionally, leaking the echo packet to 434 the peer node may not be desirable for network operators. 436 5.2.1. Initiator Node Procedures 438 If the bottom-most label in the label stack is BGP Peer Segment 439 label, the initiating node MUST set the TTL of the bottom-most label 440 to 1 to ensure that MPLS TTL expires at the BGP EPE node, and the 441 echo packet does not leak to the BGP peer node. Echo packet MUST 442 include one of BGP-Node-SID, BGP-Adj-SID, or Peer-Set-SID sub-TLV in 443 the Target FEC Stack TLV corresponding to the BGP Peer Segment label. 444 Operator MAY push one or more transport labels on top of the BGP Peer 445 Segment label to forward the echo packet to the BGP EPE node. 447 5.2.2. Responder Node Procedures 449 In addition to procedures defined in [RFC8029], the responding node, 450 upon TTL expiry of the echo packet, MUST process the incoming BGP 451 Peer Segment sub-TLV of the Target FEC Stack. It MUST validate that 452 contents of the sub-TLV and ensure the incoming label is advertised 453 for the processed BGP Peer Segment sub-TLV. 455 5.3. Path Binding SID 457 5.3.1. Initiator Node Procedures 459 Similar to BGP Peering Segment sub-TLVs, Path Binding SID sub-TLV 460 MUST be validated at the node assigning and advertising the Binding 461 SID, instead of the endpoint of the path associated with the Binding 462 SID. The initiating node MUST set the TTL of the Binding SID label 463 to 1 and include the associated Path Binding SID TLV in the Target 464 FEC Stack TLV of the echo request. Operator MAY push one or more 465 transport labels on top of Binding SID label to forward echo packet 466 from initiating node to the assigning node. 468 5.3.2. Responder Node Procedures 470 In addition to procedures defined in [RFC8029], the responding node, 471 upon TTL expiry of the echo packet, MUST process the incoming Path 472 Binding SID sub-TLV of the Target FEC Stack. The responding node 473 MUST ensure that it is the advertising node specified in the Path 474 Bindng SID sub-TLV, and the incoming Binding SID label matches the 475 advertised label value. 477 6. IANA Considerations 479 To be Updated. 481 7. Security Considerations 483 To be Updated 485 8. Acknowledgement 487 TBD 489 9. Contributors 491 TBD 493 10. References 495 10.1. Normative References 497 [I-D.ietf-idr-bgp-prefix-sid] 498 Previdi, S., Filsfils, C., Lindem, A., Sreekantiah, A., 499 and H. Gredler, "Segment Routing Prefix SID extensions for 500 BGP", draft-ietf-idr-bgp-prefix-sid-27 (work in progress), 501 June 2018. 503 [I-D.ietf-idr-bgpls-segment-routing-epe] 504 Previdi, S., Filsfils, C., Patel, K., Ray, S., and J. 505 Dong, "BGP-LS extensions for Segment Routing BGP Egress 506 Peer Engineering", draft-ietf-idr-bgpls-segment-routing- 507 epe-15 (work in progress), March 2018. 509 [I-D.sivabalan-pce-binding-label-sid] 510 Sivabalan, S., Tantsura, J., Filsfils, C., Previdi, S., 511 Hardwick, J., and D. Dhody, "Carrying Binding Label/ 512 Segment-ID in PCE-based Networks.", draft-sivabalan-pce- 513 binding-label-sid-04 (work in progress), March 2018. 515 [I-D.voyer-spring-sr-p2mp-policy] 516 daniel.voyer@bell.ca, d., Hassen, C., Gillis, K., 517 Filsfils, C., Parekh, R., and H. Bidgoli, "SR Replication 518 Policy for P2MP Service Delivery", draft-voyer-spring-sr- 519 p2mp-policy-01 (work in progress), October 2018. 521 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 522 Requirement Levels", BCP 14, RFC 2119, 523 DOI 10.17487/RFC2119, March 1997, 524 . 526 [RFC3443] Agarwal, P. and B. Akyol, "Time To Live (TTL) Processing 527 in Multi-Protocol Label Switching (MPLS) Networks", 528 RFC 3443, DOI 10.17487/RFC3443, January 2003, 529 . 531 [RFC4203] Kompella, K., Ed. and Y. Rekhter, Ed., "OSPF Extensions in 532 Support of Generalized Multi-Protocol Label Switching 533 (GMPLS)", RFC 4203, DOI 10.17487/RFC4203, October 2005, 534 . 536 [RFC5307] Kompella, K., Ed. and Y. Rekhter, Ed., "IS-IS Extensions 537 in Support of Generalized Multi-Protocol Label Switching 538 (GMPLS)", RFC 5307, DOI 10.17487/RFC5307, October 2008, 539 . 541 [RFC8029] Kompella, K., Swallow, G., Pignataro, C., Ed., Kumar, N., 542 Aldrin, S., and M. Chen, "Detecting Multiprotocol Label 543 Switched (MPLS) Data-Plane Failures", RFC 8029, 544 DOI 10.17487/RFC8029, March 2017, 545 . 547 [RFC8287] Kumar, N., Ed., Pignataro, C., Ed., Swallow, G., Akiya, 548 N., Kini, S., and M. Chen, "Label Switched Path (LSP) 549 Ping/Traceroute for Segment Routing (SR) IGP-Prefix and 550 IGP-Adjacency Segment Identifiers (SIDs) with MPLS Data 551 Planes", RFC 8287, DOI 10.17487/RFC8287, December 2017, 552 . 554 [RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L., 555 Decraene, B., Litkowski, S., and R. Shakir, "Segment 556 Routing Architecture", RFC 8402, DOI 10.17487/RFC8402, 557 July 2018, . 559 10.2. Informative References 561 [I-D.ietf-isis-segment-routing-extensions] 562 Previdi, S., Ginsberg, L., Filsfils, C., Bashandy, A., 563 Gredler, H., Litkowski, S., Decraene, B., and J. Tantsura, 564 "IS-IS Extensions for Segment Routing", draft-ietf-isis- 565 segment-routing-extensions-19 (work in progress), July 566 2018. 568 [I-D.ietf-ospf-ospfv3-segment-routing-extensions] 569 Psenak, P., Filsfils, C., Previdi, S., Gredler, H., 570 Shakir, R., Henderickx, W., and J. Tantsura, "OSPFv3 571 Extensions for Segment Routing", draft-ietf-ospf-ospfv3- 572 segment-routing-extensions-15 (work in progress), August 573 2018. 575 [I-D.ietf-ospf-segment-routing-extensions] 576 Psenak, P., Previdi, S., Filsfils, C., Gredler, H., 577 Shakir, R., Henderickx, W., and J. Tantsura, "OSPF 578 Extensions for Segment Routing", draft-ietf-ospf-segment- 579 routing-extensions-25 (work in progress), April 2018. 581 [I-D.ietf-spring-segment-routing-central-epe] 582 Filsfils, C., Previdi, S., Dawra, G., Aries, E., and D. 583 Afanasiev, "Segment Routing Centralized BGP Egress Peer 584 Engineering", draft-ietf-spring-segment-routing-central- 585 epe-10 (work in progress), December 2017. 587 [I-D.ietf-spring-segment-routing-ldp-interop] 588 Bashandy, A., Filsfils, C., Previdi, S., Decraene, B., and 589 S. Litkowski, "Segment Routing interworking with LDP", 590 draft-ietf-spring-segment-routing-ldp-interop-15 (work in 591 progress), September 2018. 593 [I-D.ietf-spring-segment-routing-mpls] 594 Bashandy, A., Filsfils, C., Previdi, S., Decraene, B., 595 Litkowski, S., and R. Shakir, "Segment Routing with MPLS 596 data plane", draft-ietf-spring-segment-routing-mpls-14 597 (work in progress), June 2018. 599 [IANA-MPLS-LSP-PING] 600 IANA, "Multi-Protocol Label Switching (MPLS) Label 601 Switched Paths (LSPs) Ping Parameters", 602 . 605 [RFC0792] Postel, J., "Internet Control Message Protocol", STD 5, 606 RFC 792, DOI 10.17487/RFC0792, September 1981, 607 . 609 Authors' Addresses 611 Nagendra Kumar (editor) 612 Cisco Systems, Inc. 613 7200-12 Kit Creek Road 614 Research Triangle Park, NC 27709-4987 615 US 617 Email: naikumar@cisco.com 618 Carlos Pignataro (editor) 619 Cisco Systems, Inc. 620 7200-11 Kit Creek Road 621 Research Triangle Park, NC 27709-4987 622 US 624 Email: cpignata@cisco.com 626 Faisal Iqbal 627 Cisco Systems, Inc. 629 Email: faiqbal@cisco.com 631 Zafar Ali 632 Cisco Systems, Inc. 634 Email: zali@cisco.com