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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references to lower-maturity documents in RFCs) ** Obsolete normative reference: RFC 3107 (Obsoleted by RFC 8277) == Outdated reference: A later version (-05) exists of draft-filsfils-spring-segment-routing-central-epe-04 == Outdated reference: A later version (-19) exists of draft-ietf-idr-bgpls-segment-routing-epe-00 == Outdated reference: A later version (-15) exists of draft-ietf-spring-segment-routing-04 == Outdated reference: A later version (-08) exists of draft-previdi-6man-segment-routing-header-07 Summary: 1 error (**), 0 flaws (~~), 5 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 IDR K. Patel 3 Internet-Draft S. Previdi 4 Intended status: Standards Track C. Filsfils 5 Expires: February 28, 2016 A. Sreekantiah 6 Cisco Systems 7 S. Ray 8 Unaffiliated 9 H. Gredler 10 Juniper Networks 11 August 27, 2015 13 Segment Routing Prefix SID extensions for BGP 14 draft-ietf-idr-bgp-prefix-sid-00 16 Abstract 18 Segment Routing (SR) architecture allows a node to steer a packet 19 flow through any topological path and service chain by leveraging 20 source routing. The ingress node prepends a SR header to a packet 21 containing a set of "segments". Each segment represents a 22 topological or a service-based instruction. Per-flow state is 23 maintained only at the ingress node of the SR domain. 25 This document describes the BGP extension for announcing BGP Prefix 26 Segment Identifier (BGP Prefix SID) information. 28 Requirements Language 30 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 31 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 32 document are to be interpreted as described in RFC 2119 [RFC2119] 33 only when they appear in all upper case. They may also appear in 34 lower or mixed case as English words, without any normative meaning. 36 Status of This Memo 38 This Internet-Draft is submitted in full conformance with the 39 provisions of BCP 78 and BCP 79. 41 Internet-Drafts are working documents of the Internet Engineering 42 Task Force (IETF). Note that other groups may also distribute 43 working documents as Internet-Drafts. The list of current Internet- 44 Drafts is at http://datatracker.ietf.org/drafts/current/. 46 Internet-Drafts are draft documents valid for a maximum of six months 47 and may be updated, replaced, or obsoleted by other documents at any 48 time. It is inappropriate to use Internet-Drafts as reference 49 material or to cite them other than as "work in progress." 51 This Internet-Draft will expire on February 28, 2016. 53 Copyright Notice 55 Copyright (c) 2015 IETF Trust and the persons identified as the 56 document authors. All rights reserved. 58 This document is subject to BCP 78 and the IETF Trust's Legal 59 Provisions Relating to IETF Documents 60 (http://trustee.ietf.org/license-info) in effect on the date of 61 publication of this document. Please review these documents 62 carefully, as they describe your rights and restrictions with respect 63 to this document. Code Components extracted from this document must 64 include Simplified BSD License text as described in Section 4.e of 65 the Trust Legal Provisions and are provided without warranty as 66 described in the Simplified BSD License. 68 Table of Contents 70 1. Segment Routing Documents . . . . . . . . . . . . . . . . . . 3 71 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 72 3. BGP-Prefix-SID . . . . . . . . . . . . . . . . . . . . . . . 4 73 3.1. MPLS Prefix Segment . . . . . . . . . . . . . . . . . . . 4 74 3.2. IPv6 Prefix Segment . . . . . . . . . . . . . . . . . . . 5 75 4. BGP-Prefix-SID Attribute . . . . . . . . . . . . . . . . . . 5 76 4.1. Label-Index TLV . . . . . . . . . . . . . . . . . . . . . 6 77 4.2. IPv6 SID . . . . . . . . . . . . . . . . . . . . . . . . 6 78 4.3. Originator SRGB TLV . . . . . . . . . . . . . . . . . . . 7 79 5. Receiving BGP-Prefix-SID Attribute . . . . . . . . . . . . . 9 80 5.1. MPLS Dataplane: Labeled Unicast . . . . . . . . . . . . . 9 81 5.2. IPv6 Dataplane . . . . . . . . . . . . . . . . . . . . . 10 82 6. Announcing BGP-Prefix-SID Attribute . . . . . . . . . . . . . 10 83 6.1. MPLS Dataplane: Labeled Unicast . . . . . . . . . . . . . 10 84 6.2. IPv6 Dataplane . . . . . . . . . . . . . . . . . . . . . 11 85 7. Error Handling of BGP-Prefix-SID Attribute . . . . . . . . . 11 86 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 87 9. Security Considerations . . . . . . . . . . . . . . . . . . . 12 88 10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 12 89 11. Change Log . . . . . . . . . . . . . . . . . . . . . . . . . 12 90 12. References . . . . . . . . . . . . . . . . . . . . . . . . . 12 91 12.1. Normative References . . . . . . . . . . . . . . . . . . 12 92 12.2. Informative References . . . . . . . . . . . . . . . . . 13 93 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14 95 1. Segment Routing Documents 97 The main references for this document are the SR architecture defined 98 in [I-D.ietf-spring-segment-routing] and the related use case 99 illustrated in [I-D.filsfils-spring-segment-routing-msdc]. 101 The Segment Routing Egress Peer Engineering architecture is described 102 in [I-D.filsfils-spring-segment-routing-central-epe]. 104 The Segment Routing Egress Peer Engineering BGPLS extensions are 105 described in [I-D.ietf-idr-bgpls-segment-routing-epe]. 107 2. Introduction 109 Segment Routing (SR) architecture leverages the source routing 110 paradigm. A group of inter-connected nodes that use SR forms a SR 111 domain. The ingress node of the SR domain prepends a SR header 112 containing "segments" to an incoming packet. Each segment represents 113 a topological instruction such as "go to prefix P following shortest 114 path" or a service instruction (e.g.: "pass through deep packet 115 inspection"). By inserting the desired sequence of instructions, the 116 ingress node is able to steer a packet via any topological path and/ 117 or service chain; per-flow state is maintained only at the ingress 118 node of the SR domain. 120 Each segment is identified by a Segment Identifier (SID). As 121 described in [I-D.ietf-spring-segment-routing], when SR is applied to 122 the MPLS dataplane the SID consists of a label while when SR is 123 applied to the IPv6 dataplane the SID consists of an IPv6 prefix (see 124 [I-D.previdi-6man-segment-routing-header]). 126 A BGP-Prefix Segment (aka BGP-Prefix-SID), is a BGP segment attached 127 to a BGP prefix. A BGP-Prefix-SID is always global within the SR/BGP 128 domain and identifies an instruction to forward the packet over the 129 ECMP-aware best-path computed by BGP to the related prefix. The BGP- 130 Prefix-SID is the identifier of the BGP prefix segment. 132 This document describes the BGP extension to signal the BGP-Prefix- 133 SID. Specifically, this document defines a new BGP attribute known 134 as the BGP Prefix SID attribute and specifies the rules to originate, 135 receive and handle error conditions of the new attribute. 137 As described in [I-D.filsfils-spring-segment-routing-msdc], the newly 138 proposed BGP Prefix-SID attribute can be attached to prefixes from 139 AFI/SAFI: 141 Multiprotocol BGP labeled IPv4/IPv6 Unicast ([RFC3107]). 143 Multiprotocol BGP ([RFC4760]) unlabeled IPv6 Unicast. 145 [I-D.filsfils-spring-segment-routing-msdc] describes use cases where 146 the Prefix-SID is used for the above AFI/SAFI. 148 3. BGP-Prefix-SID 150 The BGP-Prefix-SID attached to a BGP prefix P represents the 151 instruction "go to Prefix P" along its BGP bestpath (potentially 152 ECMP-enabled). 154 3.1. MPLS Prefix Segment 156 The BGP Prefix Segment is realized on the MPLS dataplane in the 157 following way: 159 According to [I-D.ietf-spring-segment-routing], each BGP speaker 160 is configured with a label block called the Segment Routing Global 161 Block (SRGB). The SRGB of a node is a local property and could be 162 different on different speakers. 164 As described in [I-D.filsfils-spring-segment-routing-msdc] the 165 operator assigns a globally unique "index", L_I, to a locally 166 sourced prefix of a BGP speaker N which is advertised to all other 167 BGP speakers in the SR domain. 169 The index L_I is a 32 bit offset in the SRGB. Each BGP speaker 170 derives its local MPLS label, L, by adding L_I to the start value 171 of its own SRGB, and programs L in its MPLS dataplane as its 172 incoming/local label for the prefix. 174 If the BGP speakers are configured with the same SRGB start value, 175 they will all program the same MPLS label for a given prefix P. 176 This has the effect of having a single label for prefix P across 177 all BGP speakers despite that the MPLS paradigm of "local label" 178 is preserved and this clearly simplifies the deployment and 179 operations of traffic engineering in BGP driven networks, as 180 described in [I-D.filsfils-spring-segment-routing-msdc]. 182 If the BGP speakers cannot be configured with the same SRGB, the 183 proposed BGP Prefix-SID attribute allows the advertisement of the 184 SRGB so each node can advertise the SRGB it's configured with. The 185 drawbacks of the use case where BGP speakers have different SRGBs are 186 documented in [I-D.filsfils-spring-segment-routing-msdc]. 188 In order to advertise the label index of a given prefix P and, 189 optionally, the SRGB, a new extension to BGP is needed: the BGP 190 Prefix SID attribute. This extension is described in subsequent 191 sections. 193 3.2. IPv6 Prefix Segment 195 As defined in [I-D.previdi-6man-segment-routing-header], in SR for 196 the IPv6 dataplane, the SRGB consists of the set of IPv6 addresses 197 used within the SR domain (as described in 198 [I-D.previdi-6man-segment-routing-header]). Therefore the BGP 199 speaker willing to process SR IPv6 packets MUST advertise an IPv6 200 prefix with the attached Prefix SID attribute and related SR IPv6 201 flag (see subsequent section). 203 As described in [I-D.filsfils-spring-segment-routing-msdc], when SR 204 is used over an IPv6 dataplane, the BGP Prefix Segment is 205 instantiated by an IPv6 prefix originated by the BGP speaker. 207 Each node advertises a globally unique IPv6 address representing 208 itself in the domain. This prefix (e.g.: its loopback interface 209 address) is advertised to all other BGP speakers in the SR domain. 211 Also, each node MUST advertise its support of Segment Routing for 212 IPv6 dataplane. This is realized using the Prefix SID Attribute 213 defined below. 215 4. BGP-Prefix-SID Attribute 217 The BGP Prefix SID attribute is an optional, transitive BGP path 218 attribute. The attribute type code is to be assigned by IANA 219 (suggested value: 40). The value field of the BGP-Prefix-SID 220 attribute has the following format: 222 The value field of the BGP Prefix SID attribute is defined here to be 223 a set of elements encoded as "Type/Length/Value" (i.e., a set of 224 TLVs). Following TLVs are defined: 226 o Label-Index TLV 228 o IPv6 SID TLV 230 o Originator SRGB TLV 232 Label-Index and Originator SRGB TLVs are used only when SR is applied 233 to the MPLS dataplane. 235 IPv6 SID TLV is used only when SR is applied to the IPv6 dataplane. 237 4.1. Label-Index TLV 239 The Label-Index TLV MUST be present in the Prefix-SID attribute 240 attached to Labeled IPv4/IPv6 unicast prefixes ([RFC3107]) and has 241 the following format: 243 0 1 2 3 244 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 1 245 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 246 | Type | Length | RESERVED | 247 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 248 | Flags | Label Index | 249 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 250 | Label Index | 251 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 253 where: 255 o Type is 1. 257 o Length: is 7, the total length of the value portion of the TLV. 259 o RESERVED: 8 bit field. SHOULD be 0 on transmission and MUST be 260 ignored on reception. 262 o Flags: 16 bits of flags. None are defined at this stage of the 263 document. The flag field SHOULD be clear on transmission and MUST 264 be ignored at reception. 266 o Label Index: 32 bit value representing the index value in the SRGB 267 space. 269 4.2. IPv6 SID 271 The IPv6-SID TLV MUST be present in the Prefix-SID attribute attached 272 to MP-BGP unlabeled IPv6 unicast prefixes ([RFC4760]) and has the 273 following format: 275 0 1 2 3 276 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 1 277 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 278 | Type | Length | RESERVED | 279 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 280 | Flags | 281 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 283 where: 285 o Type is 2. 287 o Length: is 3, the total length of the value portion of the TLV. 289 o RESERVED: 8 bit field. SHOULD be 0 on transmission and MUST be 290 ignored on reception. 292 o Flags: 16 bits of flags defined as follow: 294 0 1 295 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 296 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 297 |S| | 298 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 300 where: 302 * S flag: if set then it means that the BGP speaker attaching the 303 Prefix-SID Attribute to a prefix is capable of processing the 304 IPv6 Segment Routing Header (SRH, 305 [I-D.previdi-6man-segment-routing-header]) for the segment 306 corresponding to the originated IPv6 prefix. The use case 307 leveraging the S flag is described in 308 [I-D.filsfils-spring-segment-routing-msdc]. 310 The other bits of the flag field SHOULD be clear on transmission 311 an MUST be ignored at reception. 313 4.3. Originator SRGB TLV 315 The Originator SRGB TLV is an optional TLV and has the following 316 format: 318 0 1 2 3 319 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 1 320 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 321 | Type | Length | Flags | 322 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 323 | Flags | 324 +-+-+-+-+-+-+-+-+ 326 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 327 | SRGB 1 (6 octets) | 328 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 329 | | 330 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 332 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 333 | SRGB n (6 octets) | 334 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 335 | | 336 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 338 where: 340 o Type is 3. 342 o Length is the total length of the value portion of the TLV: 2 + 343 multiple of 6. 345 o Flags: 16 bits of flags. None are defined in this document. 346 Flags SHOULD be clear on transmission an MUST be ignored at 347 reception. 349 o SRGB: 3 octets of base followed by 3 octets of range. Note that 350 SRGB field MAY appear multiple times. 352 The Originator SRGB TLV contains the SRGB of the router originating 353 the prefix to which the BGP Prefix SID is attached and MUST be kept 354 in the Prefix-SID Attribute unchanged during the propagation of the 355 BGP update. 357 The originator SRGB describes the SRGB of the node where the BGP 358 Prefix Segment end. It is used to build SRTE policies when different 359 SRGB's are used in the fabric 360 ([I-D.filsfils-spring-segment-routing-msdc]). 362 The originator SRGB may only appear on Prefix-SID attribute attached 363 to prefixes of SAFI 4 (labeled unicast, [RFC3107]). 365 5. Receiving BGP-Prefix-SID Attribute 367 A BGP speaker receiving a BGP Prefix-SID attribute from an EBGP 368 neighbor residing outside the boundaries of the SR domain, SHOULD 369 discard the attribute unless it is configured to accept the attribute 370 from the EBGP neighbor. A BGP speaker MAY log an error for further 371 analysis when discarding an attribute. 373 5.1. MPLS Dataplane: Labeled Unicast 375 The Prefix-SID attribute MUST contain the Label-Index TLV and MAY 376 contain the Originator SRGB. A BGP Prefix-SID attribute received 377 without a Label-Index TLV MUST be considered as "unacceptable" by the 378 receiving speaker. 380 A BGP speaker may be locally configured with an SRGB=[GB_S, GB_E]. 381 The preferred method for deriving the SRGB is a matter of local 382 router configuration. 384 Given a label index L_I, we call L = L_I + GB_S as the derived label. 385 A BGP Prefix-SID attribute is called "unacceptable" for a speaker M 386 if the derived label value L lies outside the SRGB configured on M. 387 Otherwise the Label Index attribute is called "acceptable" to speaker 388 M. 390 The mechanisms through which a given label_index value is assigned to 391 a given prefix are outside the scope of this document. The label- 392 index value associated with a prefix is locally configured at the BGP 393 router originating the prefix. 395 The Prefix-SID attribute MUST contain the Label-Index TLV and MAY 396 contain the Originator SRGB TLV. A BGP Prefix-SID attribute received 397 without a Label-Index TLV MUST be considered as "unacceptable" by the 398 receiving speaker. 400 When a BGP speaker receives a path from a neighbor with an acceptable 401 BGP Prefix-SID attribute, it SHOULD program the derived label as the 402 local label for the prefix in its MPLS dataplane. In case of any 403 error, a BGP speaker MUST resort to the error handling rules 404 specified in Section 7. A BGP speaker MAY log an error for further 405 analysis. 407 When a BGP speaker receives a path from a neighbor with an 408 unacceptable BGP Prefix-SID attribute, for the purpose of label 409 allocation, it SHOULD treat the path as if it came without a Prefix- 410 SID attribute. A BGP speaker MAY choose to assign a local (also 411 called dynamic) label (non-SRGB) for such a prefix. A BGP speaker 412 MAY log an error for further analysis. 414 A BGP speaker receiving a prefix with a Prefix-SID attribute and a 415 label NLRI field of implicit-null from a neighbor MUST adhere to 416 standard behavior and program its MPLS dataplane to pop the top label 417 when forwarding traffic to the prefix. The label NLRI defines the 418 outbound label that MUST be used by the receiving node. The Label 419 Index gives a hint to the receiving node on which local/incoming 420 label the BGP speaker SHOULD use. 422 5.2. IPv6 Dataplane 424 When a SR IPv6 BGP speaker receives a IPv6 Unicast BGP Update with a 425 prefix having the BGP Prefix SID attribute attached, it checks 426 whether the IPv6 SID TLV is present and if the S-flag is set. If the 427 IPv6 SID TLV is not present or if the S-flag is not set, then the 428 Prefix-SID attribute MUST be considered as "unacceptable" by the 429 receiving speaker. 431 The Originator SRGB MUST be ignored on reception. 433 A BGP speaker receiving a BGP Prefix-SID attribute from an EBGP 434 neighbor residing outside the boundaries of the SR domain, SHOULD 435 discard the attribute unless it is configured to accept the attribute 436 from the EBGP neighbor. A BGP speaker MAY log an error for further 437 analysis when discarding an attribute. 439 6. Announcing BGP-Prefix-SID Attribute 441 The BGP Prefix-SID attribute MAY be attached to labeled BGP prefixes 442 (IPv4/IPv6) [RFC3107]or to IPv6 prefixes [RFC4760]. In order to 443 prevent distribution of the BGP Prefix-SID attribute beyond its 444 intended scope of applicability, attribute filtering MAY be deployed. 446 6.1. MPLS Dataplane: Labeled Unicast 448 A BGP speaker that originates a prefix attaches the Prefix-SID 449 attribute when it advertises the prefix to its neighbors. The value 450 of the Label-Index in the Label-Index TLV is determined by 451 configuration. 453 A BGP speaker that originates a Prefix-SID attribute MAY optionally 454 announce Originator SRGB TLV along with the mandatory Label-Index 455 TLV. The content of the Originator SRGB TLV is determined by the 456 configuration. 458 Since the Label-index value must be unique within an SR domain, by 459 default an implementation SHOULD NOT advertise the BGP Prefix-SID 460 attribute outside an Autonomous System unless it is explicitly 461 configured to do so. 463 A BGP speaker that advertises a path received from one of its 464 neighbors SHOULD advertise the Prefix-SID received with the path 465 without modification regardless of whether the Prefix-SID was 466 acceptable. If the path did not come with a Prefix-SID attribute, 467 the speaker MAY attach a Prefix-SID to the path if configured to do 468 so. The content of the TLVs present in the Prefix-SID is determined 469 by the configuration. 471 In all cases, the label field of the NLRI ([RFC3107], [RFC4364]) MUST 472 be set to the local/incoming label programmed in the MPLS dataplane 473 for the given prefix. If the prefix is associated with one of the 474 BGP speakers interfaces, this label is the usual MPLS label (such as 475 the implicit or explicit NULL label). 477 6.2. IPv6 Dataplane 479 A BGP speaker that originates a prefix attaches the Prefix-SID 480 attribute when it advertises the prefix to its neighbors. The IPv6 481 SID TLV MUST be present and the S-flag MUST be set. 483 A BGP speaker that advertises a path received from one of its 484 neighbors SHOULD advertise the Prefix-SID received with the path 485 without modification regardless of whether the Prefix-SID was 486 acceptable. If the path did not come with a Prefix-SID attribute, 487 the speaker MAY attach a Prefix-SID to the path if configured to do 488 so. The IPv6-SID TLV MUST be present in the Prefix-SID and with the 489 S-flag set. 491 7. Error Handling of BGP-Prefix-SID Attribute 493 When a BGP Speaker receives a BGP Update message containing a 494 malformed BGP Prefix-SID attribute, it MUST ignore the received BGP 495 Prefix-SID attributes and not pass it to other BGP peers. This is 496 equivalent to the -attribute discard- action specified in [RFC7606]. 497 When discarding an attribute, a BGP speaker MAY log an error for 498 further analysis. 500 If the BGP Prefix-SID attribute appears more than once in an BGP 501 Update message message, then, according to [RFC7606], all the 502 occurrences of the attribute other than the first one SHALL be 503 discarded and the BGP Update message shall continue to be processed. 505 When a BGP speaker receives an unacceptable Prefix-SID attribute, it 506 MAY log an error for further analysis. 508 8. IANA Considerations 510 This document defines a new BGP path attribute known as the BGP 511 Prefix-SID attribute. This document requests IANA to assign a new 512 attribute code type (suggested value: 40) for BGP the Prefix-SID 513 attribute from the BGP Path Attributes registry. 515 This document defines two new TLVs for BGP Prefix-SID attribute. 516 These TLVs need to be registered with IANA. We request IANA to 517 create a new registry for BGP Prefix-SID Attribute TLVs as follows: 519 Under "Border Gateway Protocol (BGP) Parameters" registry, "BGP 520 Prefix SID attribute Types" Reference: draft-ietf-idr-bgp-prefix- 521 sid-00 Registration Procedure(s): Values 1-254 First Come, First 522 Served, Value 0 and 255 reserved 524 Value Type Reference 525 0 Reserved draft-ietf-idr-bgp-prefix-sid-00 526 1 Label-Index draft-ietf-idr-bgp-prefix-sid-00 527 2 IPv6 SID draft-ietf-idr-bgp-prefix-sid-00 528 3 Originator SRGB draft-ietf-idr-bgp-prefix-sid-00 529 4-254 Unassigned 530 255 Reserved draft-ietf-idr-bgp-prefix-sid-00 532 9. Security Considerations 534 This document introduces no new security considerations above and 535 beyond those already specified in [RFC4271] and [RFC3107]. 537 10. Acknowledgements 539 The authors would like to thanks Satya Mohanty and Acee Lindem for 540 their contribution to this document. 542 11. Change Log 544 Initial Version: Sep 21 2014 546 12. References 548 12.1. Normative References 550 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 551 Requirement Levels", BCP 14, RFC 2119, 552 DOI 10.17487/RFC2119, March 1997, 553 . 555 [RFC3107] Rekhter, Y. and E. Rosen, "Carrying Label Information in 556 BGP-4", RFC 3107, DOI 10.17487/RFC3107, May 2001, 557 . 559 [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A 560 Border Gateway Protocol 4 (BGP-4)", RFC 4271, 561 DOI 10.17487/RFC4271, January 2006, 562 . 564 [RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private 565 Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364, February 566 2006, . 568 [RFC7606] Chen, E., Ed., Scudder, J., Ed., Mohapatra, P., and K. 569 Patel, "Revised Error Handling for BGP UPDATE Messages", 570 RFC 7606, DOI 10.17487/RFC7606, August 2015, 571 . 573 12.2. Informative References 575 [I-D.filsfils-spring-segment-routing-central-epe] 576 Filsfils, C., Previdi, S., Patel, K., shaw@fb.com, s., 577 Ginsburg, D., and D. Afanasiev, "Segment Routing 578 Centralized Egress Peer Engineering", draft-filsfils- 579 spring-segment-routing-central-epe-04 (work in progress), 580 July 2015. 582 [I-D.filsfils-spring-segment-routing-msdc] 583 Filsfils, C., Previdi, S., Mitchell, J., Lapukhov, P., 584 Gaya, G., Afanasiev, D., Laberge, T., Nkposong, E., 585 Nanduri, M., Uttaro, J., and S. Ray, "BGP-Prefix Segment 586 in large-scale data centers", draft-filsfils-spring- 587 segment-routing-msdc-03 (work in progress), July 2015. 589 [I-D.ietf-idr-bgpls-segment-routing-epe] 590 Previdi, S., Filsfils, C., Ray, S., Patel, K., Dong, J., 591 and M. Chen, "Segment Routing Egress Peer Engineering BGP- 592 LS Extensions", draft-ietf-idr-bgpls-segment-routing- 593 epe-00 (work in progress), June 2015. 595 [I-D.ietf-spring-segment-routing] 596 Filsfils, C., Previdi, S., Decraene, B., Litkowski, S., 597 and r. rjs@rob.sh, "Segment Routing Architecture", draft- 598 ietf-spring-segment-routing-04 (work in progress), July 599 2015. 601 [I-D.previdi-6man-segment-routing-header] 602 Previdi, S., Filsfils, C., Field, B., Leung, I., Vyncke, 603 E., and D. Lebrun, "IPv6 Segment Routing Header (SRH)", 604 draft-previdi-6man-segment-routing-header-07 (work in 605 progress), July 2015. 607 [RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter, 608 "Multiprotocol Extensions for BGP-4", RFC 4760, 609 DOI 10.17487/RFC4760, January 2007, 610 . 612 Authors' Addresses 614 Keyur Patel 615 Cisco Systems 616 170 W. Tasman Drive 617 San Jose, CA 95124 95134 618 USA 620 Email: keyupate@cisco.com 622 Stefano Previdi 623 Cisco Systems 624 Via Del Serafico, 200 625 Rome 00142 626 Italy 628 Email: sprevidi@cisco.com 630 Clarence Filsfils 631 Cisco Systems 632 Brussels 633 Belgium 635 Email: cfilsfils@cisco.com 637 Arjun Sreekantiah 638 Cisco Systems 639 170 W. Tasman Drive 640 San Jose, CA 95124 95134 641 USA 643 Email: asreekan@cisco.com 644 Saikat Ray 645 Unaffiliated 647 Email: raysaikat@gmail.com 649 Hannes Gredler 650 Juniper Networks 652 Email: hannes@juniper.net