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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group A. Lindem 3 Internet-Draft Cisco Systems 4 Intended status: Standards Track J. Arkko 5 Expires: February 28, 2015 Ericsson 6 August 27, 2014 8 OSPFv3 Auto-Configuration 9 draft-ietf-ospf-ospfv3-autoconfig-08.txt 11 Abstract 13 OSPFv3 is a candidate for deployments in environments where auto- 14 configuration is a requirement. One such environment is the IPv6 15 home network where users expect to simply plug in a router and have 16 it automatically use OSPFv3 for intra-domain routing. This document 17 describes the necessary mechanisms for OSPFv3 to be self-configuring. 19 Status of this Memo 21 This Internet-Draft is submitted in full conformance with the 22 provisions of BCP 78 and BCP 79. 24 Internet-Drafts are working documents of the Internet Engineering 25 Task Force (IETF). Note that other groups may also distribute 26 working documents as Internet-Drafts. The list of current Internet- 27 Drafts is at http://datatracker.ietf.org/drafts/current/. 29 Internet-Drafts are draft documents valid for a maximum of six months 30 and may be updated, replaced, or obsoleted by other documents at any 31 time. It is inappropriate to use Internet-Drafts as reference 32 material or to cite them other than as "work in progress." 34 This Internet-Draft will expire on February 28, 2015. 36 Copyright Notice 38 Copyright (c) 2014 IETF Trust and the persons identified as the 39 document authors. All rights reserved. 41 This document is subject to BCP 78 and the IETF Trust's Legal 42 Provisions Relating to IETF Documents 43 (http://trustee.ietf.org/license-info) in effect on the date of 44 publication of this document. Please review these documents 45 carefully, as they describe your rights and restrictions with respect 46 to this document. Code Components extracted from this document must 47 include Simplified BSD License text as described in Section 4.e of 48 the Trust Legal Provisions and are provided without warranty as 49 described in the Simplified BSD License. 51 This document may contain material from IETF Documents or IETF 52 Contributions published or made publicly available before November 53 10, 2008. The person(s) controlling the copyright in some of this 54 material may not have granted the IETF Trust the right to allow 55 modifications of such material outside the IETF Standards Process. 56 Without obtaining an adequate license from the person(s) controlling 57 the copyright in such materials, this document may not be modified 58 outside the IETF Standards Process, and derivative works of it may 59 not be created outside the IETF Standards Process, except to format 60 it for publication as an RFC or to translate it into languages other 61 than English. 63 Table of Contents 65 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 66 1.1. Requirements notation . . . . . . . . . . . . . . . . . . 3 67 1.2. Acknowledgments . . . . . . . . . . . . . . . . . . . . . 3 68 2. OSPFv3 Default Configuration . . . . . . . . . . . . . . . . . 5 69 3. OSPFv3 HelloInterval/RouterDeadInterval Flexibility . . . . . 7 70 3.1. Wait Timer Reduction . . . . . . . . . . . . . . . . . . . 7 71 4. OSPFv3 Minimal Authentication Configuration . . . . . . . . . 8 72 5. OSPFv3 Router ID Selection . . . . . . . . . . . . . . . . . . 9 73 6. OSPFv3 Adjacency Formation . . . . . . . . . . . . . . . . . . 10 74 7. OSPFv3 Duplicate Router ID Detection and Resolution . . . . . 11 75 7.1. Duplicate Router ID Detection for Neighbors . . . . . . . 11 76 7.2. Duplicate Router ID Detection for OSPFv3 Routers that 77 are not Neighbors . . . . . . . . . . . . . . . . . . . . 11 78 7.2.1. OSPFv3 Router Auto-Configuration LSA . . . . . . . . . 11 79 7.2.2. Router-Hardware-Fingerprint TLV . . . . . . . . . . . 13 80 7.3. Duplicate Router ID Resolution . . . . . . . . . . . . . . 14 81 7.4. Change to RFC 2328 Section 13.4, 'Receiving 82 Self-Originated LSA' Processing . . . . . . . . . . . . . 14 83 8. Security Considerations . . . . . . . . . . . . . . . . . . . 15 84 9. Management Considerations . . . . . . . . . . . . . . . . . . 16 85 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17 86 11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 18 87 11.1. Normative References . . . . . . . . . . . . . . . . . . . 18 88 11.2. Informative References . . . . . . . . . . . . . . . . . . 18 89 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 19 91 1. Introduction 93 OSPFv3 [OSPFV3] is a candidate for deployments in environments where 94 auto-configuration is a requirement. Its operation is largely 95 unchanged from the base OSPFv3 protocol specification [OSPFV3]. 97 The following aspects of OSPFv3 auto-configuration are described: 99 1. Default OSPFv3 Configuration 101 2. HelloInterval/RouterDeadInterval Flexibility 103 3. Unique OSPFv3 Router-ID generation 105 4. OSPFv3 Adjacency Formation 107 5. Duplicate OSPFv3 Router-ID Resolution 109 1.1. Requirements notation 111 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 112 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 113 document are to be interpreted as described in [RFC-KEYWORDS]. 115 1.2. Acknowledgments 117 This specification was inspired by the work presented in the Homenet 118 working group meeting in October 2011 in Philadelphia, Pennsylvania. 119 In particular, we would like to thank Fred Baker, Lorenzo Colitti, 120 Ole Troan, Mark Townsley, and Michael Richardson. 122 Arthur Dimitrelis and Aidan Williams did prior work in OSPFv3 auto- 123 configuration in the expired "Autoconfiguration of routers using a 124 link state routing protocol" IETF Draft. There are many similarities 125 between the concepts and techniques in this document. 127 Thanks for Abhay Roy and Manav Bhatia for comments regarding 128 duplicate router-id processing. 130 Thanks for Alvaro Retana and Michael Barnes for comments regarding 131 OSPFv3 Instance ID auto-configuration. 133 Thanks to Faraz Shamim for review and comments. 135 Thanks to Mark Smith for the requirement to reduce the adjacency 136 formation delay in the back-to-back ethernet topologies that are 137 prevalent in home networks. 139 Thanks to Les Ginsberg for document review and recommendations on 140 OSPFv3 hardware fingerprint content. 142 Thanks to Curtis Villamizar for document review and analysis of 143 duplicate router-id resolution nuances. 145 Thanks to Uma Chunduri for comments during OSPF WG last call. 147 Special thanks go to Markus Stenberg for his implementation of this 148 specification in Bird. 150 Special thanks also go to David Lamparter for his implementation of 151 this specification in Quagga. 153 The RFC text was produced using Marshall Rose's xml2rfc tool. 155 2. OSPFv3 Default Configuration 157 For complete auto-configuration, OSPFv3 will need to choose suitable 158 configuration defaults. These include: 160 1. Area 0 Only - All auto-configured OSPFv3 interfaces MUST be in 161 area 0. 163 2. OSPFv3 SHOULD be auto-configured on for IPv6 on all interfaces 164 intended as general IPv6-capable routers. Optionally, an 165 interface MAY be excluded if it is clear that running OSPFv3 on 166 the interface is not required. For example, if manual 167 configuration or another condition indicates that an interface is 168 connected to an Internet Service Provider (ISP) and there is no 169 Border Gateway Protocol (BGP) [BGP] peering, there is typically 170 no need to employ OSPFv3. In fact, [IPv6-CPE] specifically 171 requires that IPv6 Customer Premise Equipment (CPE) routers do 172 not initiate any dynamic routing protocol by default on the 173 router's WAN, i.e., ISP-facing, interface. In home networking 174 environments, an interface where no OSPFv3 neighbors are found 175 but a DHCP IPv6 prefix can be acquired may be considered an ISP- 176 facing interface and running OSPFv3 is unnecessary. 178 3. OSPFv3 interfaces will be auto-configured to an interface type 179 corresponding to their layer-2 capability. For example, Ethernet 180 interfaces and vanilla Wi-Fi interfaces will be auto-configured 181 as OSPFv3 broadcast networks and Point-to-Point Protocol (PPP) 182 interfaces will be auto-configured as OSPFv3 Point-to-Point 183 interfaces. Most extant OSPFv3 implementations do this already. 184 Auto-configured operation over wireless networks requiring a 185 point-to-multipoint (P2MP) topology and dynamic metrics based on 186 wireless feedback is not within the scope of this document. 187 However, auto-configuration is not precluded in these 188 environments. 190 4. OSPFv3 interfaces MAY use an arbitrary HelloInterval and 191 RouterDeadInterval as specified in Section 3. Of course, an 192 identical HelloInterval and RouterDeadInterval will still be 193 required to form an adjacency with an OSPFv3 router not 194 supporting auto-configuration [OSPFV3]. 196 5. All OSPFv3 interfaces SHOULD be auto-configured to use an 197 Interface Instance ID of 0 that corresponds to the base IPv6 198 unicast address family instance ID as defined in [OSPFV3-AF]. 199 Similarly, if IPv4 unicast addresses are advertised in a separate 200 auto-configured OSPFv3 instance, the base IPv4 unicast address 201 family instance ID value, i.e., 64, SHOULD be auto-configured as 202 the Interface Instance ID for all interfaces corresponding to the 203 IPv4 unicast OSPFv3 instance [OSPFV3-AF]. 205 3. OSPFv3 HelloInterval/RouterDeadInterval Flexibility 207 Auto-configured OSPFv3 routers will not require an identical 208 HelloInterval and RouterDeadInterval to form adjacencies. Rather, 209 the received HelloInterval will be ignored and the received 210 RouterDeadInterval will be used to determine OSPFv3 liveliness with 211 the sending router. In other words, the Neighbor Inactivity Timer 212 (Section 10 of [OSPFV2]) for each neighbor will reflect that 213 neighbor's advertised RouterDeadInterval and MAY be different from 214 other OSPFv3 routers on the link without impacting adjacency 215 formation. A similar mechanism requiring additional signaling is 216 proposed for all OSPFv2 and OSPFv3 routers [ASYNC-HELLO]. 218 3.1. Wait Timer Reduction 220 In many situations, auto-configured OSPFv3 routers will be deployed 221 in environments where back-to-back ethernet connections are utilized. 222 When this is the case, an OSPFv3 broadcast interface will not come up 223 until the other OSPFv3 router is connected and the routers will wait 224 RouterDeadInterval seconds before forming an adjacency [OSPFV2]. In 225 order to reduce this delay, an auto-configured OSPFv3 router MAY 226 reduce the wait interval to a value no less than (HelloInterval + 1). 227 Reducing the setting will slightly increase the likelihood of the 228 Designated Router (DR) flapping but is preferable to the long 229 adjacency formation delay. Note that this value is not included in 230 OSPFv3 Hello packets and does not impact interoperability. 232 4. OSPFv3 Minimal Authentication Configuration 234 In many deployments, the requirement for OSPFv3 authentication 235 overrides the goal of complete OSPFv3 autoconfiguration. Therefore, 236 it is RECOMMENDED that OSPFv3 routers supporting this specification 237 minimally offer an option to explicitly configure a single password 238 for HMAC-SHA authentication as described in [OSPFV3-AUTH-TRAILER]. 239 When configured, the password will be used on all auto-configured 240 interfaces with the Security Association Identifier (SA ID) set to 1 241 and HMAC-SHA-256 used as the authentication algorithm. 243 5. OSPFv3 Router ID Selection 245 As OSPFv3 Router implementing this specification must select a unique 246 Router ID. A pseudo-random number SHOULD be used for the OSPFv3 247 Router ID. The generation should be seeded with a variable that is 248 likely to be unique in the applicable OSPFv3 router deployment. A 249 good choice of seed would be some portion or hash of the Router- 250 Hardware-Fingerprint as described in Section 7.2.2. 252 Since there is a possibility of a Router ID collision, duplicate 253 Router ID detection and resolution are required as described in 254 Section 7 and Section 7.3. OSPFv3 Routers SHOULD maintain the last 255 successfully chosen Router ID in non-volatile storage to avoid 256 collisions subsequent to when an autoconfigured OSPFv3 router is 257 first added to the OSPFv3 routing domain. 259 6. OSPFv3 Adjacency Formation 261 Since OSPFv3 uses IPv6 link-local addresses for all protocol messages 262 other than messages sent on virtual links (which are not applicable 263 to auto-configuration), OSPFv3 adjacency formation can proceed as 264 soon as a Router ID has been selected and the IPv6 link-local address 265 has completed Duplicate Address Detection (DAD) as specified in IPv6 266 Stateless Address Autoconfiguration [SLAAC]. Otherwise, the only 267 changes to the OSPFv3 base specification are supporting 268 HelloInterval/RouterDeadInterval flexibility as described in 269 Section 3 and duplicate Router ID detection and resolution as 270 described in Section 7 and Section 7.3. 272 7. OSPFv3 Duplicate Router ID Detection and Resolution 274 There are two cases of duplicate OSPFv3 Router ID detection. One 275 where the OSPFv3 router with the duplicate Router ID is directly 276 connected and one where it is not. In both cases, the duplicate 277 resolution is for one of the routers to select a new OSPFv3 Router 278 ID. 280 7.1. Duplicate Router ID Detection for Neighbors 282 In this case, a duplicate Router ID is detected if any valid OSPFv3 283 packet is received with the same OSPFv3 Router ID but a different 284 IPv6 link-local source address. Once this occurs, the OSPFv3 router 285 with the numerically smaller IPv6 link-local address will need to 286 select a new Router ID as described in Section 7.3. Note that the 287 fact that the OSPFv3 router is a neighbor on a non-virtual interface 288 implies that the router is directly connected. An OSPFv3 router 289 implementing this specification should assure that the inadvertent 290 connection of multiple router interfaces to the same physical link is 291 not misconstrued as detection of an OSPFv3 neighbor with a duplicate 292 Router ID. 294 7.2. Duplicate Router ID Detection for OSPFv3 Routers that are not 295 Neighbors 297 OSPFv3 Routers implementing auto-configuration, as specified herein, 298 MUST originate an Auto-Configuration (AC) Link State Advertisement 299 (LSA) including the Router-Hardware-Fingerprint Type-Length-Value 300 (TLV). The Router-Hardware-Fingerprint TLV contains a variable 301 length value that has a very high probability of uniquely identifying 302 the advertising OSPFv3 router. An OSPFv3 router implementing this 303 specification MUST compare a received self-originated Auto- 304 Configuration LSA's Router-Hardware-Fingerprint TLV against its own 305 router hardware fingerprint. If the fingerprints are not equal, 306 there is a duplicate Router ID conflict and the OSPFv3 Router with 307 the numerically smaller router hardware fingerprint MUST select a new 308 Router ID as described in Section 7.3. 310 This new LSA is designated for information related to OSPFv3 Auto- 311 configuration and, in the future, could be used other auto- 312 configuration information, e.g., global IPv6 prefixes. However, this 313 is beyond the scope of this document. 315 7.2.1. OSPFv3 Router Auto-Configuration LSA 317 The OSPFv3 Auto-Configuration (AC) LSA has a function code of TBD and 318 the S2/S1 bits set to 01 indicating Area Flooding Scope. The U bit 319 will be set indicating that the OSPFv3 AC LSA should be flooded even 320 if it is not understood. The Link State ID (LSID) value will be a 321 integer index used to discriminate between multiple AC LSAs 322 originated by the same OSPFv3 Router. This specification only 323 describes the contents of an AC LSA with a Link State ID (LSID) of 0. 325 0 1 2 3 326 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 1 327 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 328 | LS age |1|0|1| TBD | 329 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 330 | Link State ID | 331 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 332 | Advertising Router | 333 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 334 | LS sequence number | 335 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 336 | LS checksum | Length | 337 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 338 | | 339 +- TLVs -+ 340 | ... | 342 OSPFv3 Auto-Configuration (AC) LSA 344 The format of the TLVs within the body of an AC LSA is the same as 345 the format used by the Traffic Engineering Extensions to OSPF [TE]. 346 The LSA payload consists of one or more nested Type/Length/Value 347 (TLV) triplets. The format of each TLV is: 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 | Length | 353 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 354 | Value... | 355 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 357 TLV Format 359 The Length field defines the length of the value portion in octets 360 (thus a TLV with no value portion would have a length of 0). The TLV 361 is padded to 4-octet alignment; padding is not included in the length 362 field (so a 3-octet value would have a length of 3, but the total 363 size of the TLV would be 8 octets). Nested TLVs are also 32-bit 364 aligned. For example, a 1-byte value would have the length field set 365 to 1, and 3 octets of padding would be added to the end of the value 366 portion of the TLV. Unrecognized types are ignored. 368 The new LSA is designated for information related to OSPFv3 Auto- 369 configuration and, in the future, can be used other auto- 370 configuration information. 372 7.2.2. Router-Hardware-Fingerprint TLV 374 The Router-Hardware-Fingerprint TLV is the first TLV defined for the 375 OSPFv3 Auto-Configuration (AC) LSA. It will have type 1 and MUST be 376 advertised in the LSID OSPFv3 AC LSA with an LSID of 0. It SHOULD 377 occur, at most, once and the first instance of the TLV will take 378 precedence over subsequent TLV instances. The length of the Router- 379 Hardware-Fingerprint is variable but must be 32 octets or greater. 381 The contents of the hardware fingerprint MUST be some combination of 382 MAC addresses, CPU ID, or serial number(s) that provides an extremely 383 high probability of uniqueness. It is RECOMMENDED that one or more 384 available universal tokens (e.g., IEEE 802 48-bit MAC addresses or 385 IEEE EUI-64 Identifiers [EUI64]) associated with the OSPFv3 router be 386 included in the hardware fingerprint. It MUST be based on hardware 387 attributes that will not change across hard and soft restarts. 389 0 1 2 3 390 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 1 391 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 392 | 1 | >32 | 393 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 394 | Router Hardware Fingerprint | 395 o 396 o 397 o 398 | | 399 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 401 Router-Hardware-Fingerprint TLV Format 403 7.3. Duplicate Router ID Resolution 405 The OSPFv3 Router selected to resolve the duplicate OSPFv3 Router ID 406 condition must select a new OSPFv3 Router ID. After selecting a new 407 Router ID, all self-originated LSAs MUST be reoriginated, and any 408 OSPFv3 neighbor adjacencies MUST be reestablished. The OSPFv3 router 409 retaining the Router ID causing the conflict will reoriginate or 410 purge stale any LSAs as described in Section 13.4 [OSPFV2]. 412 7.4. Change to RFC 2328 Section 13.4, 'Receiving Self-Originated LSA' 413 Processing 415 RFC 2328 [OSPFV2], Section 13.4, describes the processing of received 416 self-originated LSAs. If the received LSA doesn't exist, the 417 receiving router will purge it from the OSPF routing domain. If the 418 LSA is newer than the version in the Link State Database (LSDB), the 419 receiving router will originate a newer version by advancing the LSA 420 sequence number and reflooding. Since it is possible for an auto- 421 configured OSPFv3 router to choose a duplicate OSPFv3 Router ID, 422 OSPFv3 routers implementing this specification should detect when 423 multiple instances of the same self-originated LSA are purged or 424 reoriginated since this is indicative of an OSPFv3 router with a 425 duplicate Router ID in the OSPFv3 routing domain. When this 426 condition is detected, the OSPFv3 Router SHOULD delay self-originated 427 LSA processing for LSAs that have recently been purged or reflooded. 428 This specification recommends 10 seconds as the interval defining 429 recent self-originated LSA processing and an exponential back off of 430 1 to 8 seconds for the processing delay. This additional delay 431 should allow for the mechanisms described in Section 7 to resolve the 432 duplicate OSPFv3 Router ID conflict. 434 8. Security Considerations 436 A unique OSPFv3 Interface Instance ID is used for auto-configuration 437 to prevent inadvertent OSPFv3 adjacency formation, see Section 2 439 The goals of security and complete OSPFv3 auto-configuration are 440 somewhat contradictory. When no explicit security configuration 441 takes place, auto-configuration implies that additional devices 442 placed in the network are automatically adopted as a part of the 443 network. However, auto-configuration can also be combined with 444 password configuration (see Section 4) or future extensions for 445 automatic pairing between devices. These mechanisms can help provide 446 an automatically configured, securely routed network. 448 9. Management Considerations 450 It is RECOMMENDED that OSPFv3 routers supporting this specification 451 also allow explicit configuration of OSPFv3 parameters as specified 452 in Appendix C of [OSPFV3]. This is in addition to the authentication 453 key configuration recommended in Section 4. However, it is 454 acknowledged that there may be some deployment scenarios where manual 455 authentication key configuration is not required. 457 Since there is a small possibility of OSPFv3 Router ID collisions, 458 manual configuration of OSPFv3 Router-IDs is RECOMMENDED in OSPFv3 459 routing domains where route recovergence due to a router ID change is 460 intolerable. 462 10. IANA Considerations 464 This specification defines an OSPFv3 LSA Type for the OSPFv3 Auto- 465 Configuration (AC) LSA, as described in Section 7.2.1. The value TBD 466 will be allocated from the existing "OSPFv3 LSA Function Code" 467 registry for the OSPFv3 Auto-Configuration LSA. 469 This specification also creates a registry for OSPFv3 Auto- 470 Configuration (AC) LSA TLVs. This registry should be placed in the 471 existing OSPFv3 IANA registry, and new values can be allocated via 472 IETF Consensus or IESG Approval. 474 Three initial values are allocated: 476 o 0 is marked as reserved. 478 o 1 is Router-Hardware-Fingerprint TLV (Section 7.2.2). 480 o 65535 is an Auto-configuration-Experiment-TLV, a common value that 481 can be used for experimental purposes. 483 11. References 485 11.1. Normative References 487 [OSPFV2] Moy, J., "OSPF Version 2", RFC 2328, April 1998. 489 [OSPFV3] Coltun, R., Ferguson, D., Moy, J., and A. Lindem, "OSPF 490 for IPv6", RFC 5340, July 2008. 492 [OSPFV3-AF] 493 Lindem, A., Mirtorabi, S., Roy, A., Barnes, M., and R. 494 Aggarwal, "Support of Address Families in OSPFv3", 495 RFC 5838, April 2010. 497 [OSPFV3-AUTH-TRAILER] 498 Bhatia, M., Manral, V., and A. Lindem, "Supporting 499 Authentication Trailer for OSPFv3", RFC 7166, 500 February 2012. 502 [RFC-KEYWORDS] 503 Bradner, S., "Key words for use in RFCs to Indicate 504 Requirement Levels", RFC 2119, March 1997. 506 [SLAAC] Thomson, S., Narten, T., and J. Tatuya, "IPv6 Stateless 507 Address Autoconfiguration", RFC 4862, September 2007. 509 [TE] Katz, D., Yeung, D., and K. Kompella, "Traffic Engineering 510 Extensions to OSPF", RFC 3630, September 2003. 512 11.2. Informative References 514 [ASYNC-HELLO] 515 Anand, M., Grover, H., and A. Roy, "Asymmetric OSPF Hold 516 Timer", draft-madhukar-ospf-agr-asymmetric-01.txt (work in 517 progress). 519 [BGP] Rekhter, Y., Li, T., and S. Hares, "A Border Gateway 520 Protocol 4 (BGP-4)", RFC 4271, January 2006. 522 [EUI64] IEEE, "Guidelines for 64-bit Global Identifier (EUI-64) 523 Registration Authority", IEEE Tutorial http:// 524 standards.ieee.org/regauth/oui/tutorials/EUI64.html, 525 March 1997. 527 [IPv6-CPE] 528 Singh, H., Beebee, W., Donley, C., Stark, B., and O. 529 Troan, "Basic Requirements for IPv6 Customer Edge 530 Routers", RFC 6204, April 2011. 532 Authors' Addresses 534 Acee Lindem 535 Cisco Systems 536 301 Midenhall Way 537 Cary, NC 27513 538 USA 540 Email: acee@cisco.com 542 Jari Arkko 543 Ericsson 544 Jorvas, 02420 545 Finland 547 Email: jari.arkko@piuha.net