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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group J. Laganier 3 Internet-Draft Juniper Networks 4 Obsoletes: 5204 (if approved) L. Eggert 5 Intended status: Standards Track NetApp 6 Expires: March 26, 2013 September 22, 2012 8 Host Identity Protocol (HIP) Rendezvous Extension 9 draft-ietf-hip-rfc5204-bis-02 11 Abstract 13 This document defines a rendezvous extension for the Host Identity 14 Protocol (HIP). The rendezvous extension extends HIP and the HIP 15 registration extension for initiating communication between HIP nodes 16 via HIP rendezvous servers. Rendezvous servers improve reachability 17 and operation when HIP nodes are multi-homed or mobile. 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 March 26, 2013. 36 Copyright Notice 38 Copyright (c) 2012 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 Table of Contents 53 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 54 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 55 3. Overview of Rendezvous Server Operation . . . . . . . . . . . 4 56 3.1. Diagram Notation . . . . . . . . . . . . . . . . . . . . . 5 57 3.2. Rendezvous Client Registration . . . . . . . . . . . . . . 6 58 3.3. Relaying the Base Exchange . . . . . . . . . . . . . . . . 6 59 4. Rendezvous Server Extensions . . . . . . . . . . . . . . . . . 7 60 4.1. RENDEZVOUS Registration Type . . . . . . . . . . . . . . . 7 61 4.2. Parameter Formats and Processing . . . . . . . . . . . . . 8 62 4.2.1. RVS_HMAC Parameter . . . . . . . . . . . . . . . . . . 8 63 4.2.2. FROM Parameter . . . . . . . . . . . . . . . . . . . . 9 64 4.2.3. VIA_RVS Parameter . . . . . . . . . . . . . . . . . . 10 65 4.3. Modified Packets Processing . . . . . . . . . . . . . . . 10 66 4.3.1. Processing Outgoing I1 Packets . . . . . . . . . . . . 10 67 4.3.2. Processing Incoming I1 Packets . . . . . . . . . . . . 11 68 4.3.3. Processing Outgoing R1 Packets . . . . . . . . . . . . 11 69 4.3.4. Processing Incoming R1 Packets . . . . . . . . . . . . 11 70 5. Security Considerations . . . . . . . . . . . . . . . . . . . 12 71 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 72 7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 13 73 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13 74 8.1. Normative References . . . . . . . . . . . . . . . . . . . 13 75 8.2. Informative References . . . . . . . . . . . . . . . . . . 14 76 Appendix A. Changes from RFC 5204 . . . . . . . . . . . . . . . . 14 78 1. Introduction 80 The Host Identity Protocol (HIP) Architecture 81 [I-D.ietf-hip-rfc4423-bis] introduces the rendezvous mechanism to 82 help a HIP node to contact a frequently moving HIP node. The 83 rendezvous mechanism involves a third party, the rendezvous server 84 (RVS), which serves as an initial contact point ("rendezvous point") 85 for its clients. The clients of an RVS are HIP nodes that use the 86 HIP Registration Extension [I-D.ietf-hip-rfc5203-bis] to register 87 their HIT->IP address mappings with the RVS. After this 88 registration, other HIP nodes can initiate a base exchange using the 89 IP address of the RVS instead of the current IP address of the node 90 they attempt to contact. Essentially, the clients of an RVS become 91 reachable at the RVS's IP address. Peers can initiate a HIP base 92 exchange with the IP address of the RVS, which will relay this 93 initial communication such that the base exchange may successfully 94 complete. 96 2. Terminology 98 This section defines terms used throughout the remainder of this 99 specification. 101 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 102 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 103 document are to be interpreted as described in RFC 2119 [RFC2119]. 105 In addition to the terminology defined in the HIP specification 106 [I-D.ietf-hip-rfc5201-bis] and the HIP Registration Extension 107 [I-D.ietf-hip-rfc5203-bis], this document defines and uses the 108 following terms: 110 Rendezvous Service 111 A HIP service provided by a rendezvous server to its rendezvous 112 clients. The rendezvous server offers to relay some of the 113 arriving base exchange packets between the initiator and 114 responder. 116 Rendezvous Server (RVS) 117 A HIP registrar providing rendezvous service. 119 Rendezvous Client 120 A HIP requester that has registered for rendezvous service at a 121 rendezvous server. 123 Rendezvous Registration 124 A HIP registration for rendezvous service, established between a 125 rendezvous server and a rendezvous client. 127 3. Overview of Rendezvous Server Operation 129 Figure 1 shows a simple HIP base exchange without a rendezvous 130 server, in which the initiator initiates the exchange directly with 131 the responder by sending an I1 packet to the responder's IP address, 132 as per the HIP specification [I-D.ietf-hip-rfc5201-bis]. 134 +-----+ +-----+ 135 | |-------I1------>| | 136 | I |<------R1-------| R | 137 | |-------I2------>| | 138 | |<------R2-------| | 139 +-----+ +-----+ 141 Figure 1: HIP base exchange without rendezvous server. 143 The End-Host Mobility and Multihoming with the Host Identity 144 Protocol specification [I-D.ietf-hip-rfc5206-bis] allows a HIP node 145 to notify its peers about changes in its set of IP addresses. This 146 specification presumes initial reachability of the two nodes with 147 respect to each other. 149 However, such a HIP node MAY also want to be reachable to other 150 future correspondent peers that are unaware of its location change. 151 The HIP Architecture [I-D.ietf-hip-rfc4423-bis] introduces rendezvous 152 servers with whom a HIP node MAY register its host identity tags 153 (HITs) and current IP addresses. An RVS relays HIP packets arriving 154 for these HITs to the node's registered IP addresses. When a HIP 155 node has registered with an RVS, it SHOULD record the IP address of 156 its RVS in its DNS record, using the HIP DNS resource record type 157 defined in the HIP DNS Extension [I-D.ietf-hip-rfc5205-bis]. 159 +-----+ 160 +--I1--->| RVS |---I1--+ 161 | +-----+ | 162 | v 163 +-----+ +-----+ 164 | |<------R1-------| | 165 | I |-------I2------>| R | 166 | |<------R2-------| | 167 +-----+ +-----+ 169 Figure 2: HIP base exchange with a rendezvous server. 171 Figure 2 shows a HIP base exchange involving a rendezvous server. It 172 is assumed that HIP node R previously registered its HITs and current 173 IP addresses with the RVS, using the HIP Registration Extension 174 [I-D.ietf-hip-rfc5203-bis]. When the initiator I tries to establish 175 contact with the responder R, it must send the I1 of the base 176 exchange either to one of R's IP addresses (if known via DNS or other 177 means) or to one of R's rendezvous servers. Here, I obtains the IP 178 address of R's rendezvous server from R's DNS record and then sends 179 the I1 packet of the HIP base exchange to RVS. RVS, noticing that 180 the HIT contained in the arriving I1 packet is not one of its own, 181 MUST check its current registrations to determine if it needs to 182 relay the packets. Here, it determines that the HIT belongs to R and 183 then relays the I1 packet to the registered IP address. R then 184 completes the base exchange without further assistance from RVS by 185 sending an R1 directly to the I's IP address, as obtained from the I1 186 packet. In this specification, the client of the RVS is always the 187 responder. However, there might be reasons to allow a client to 188 initiate a base exchange through its own RVS, like NAT and firewall 189 traversal. This specification does not address such scenarios, which 190 should be specified in other documents. 192 3.1. Diagram Notation 194 Notation Significance 195 -------- ------------ 197 I, R I and R are the respective source and destination IP 198 addresses in the IP header. 200 HIT-I, HIT-R HIT-I and HIT-R are the initiator's and the 201 responder's HITs in the packet, respectively. 203 REG_REQ A REG_REQUEST parameter is present in the HIP header. 205 REG_RES A REG_RESPONSE parameter is present in the HIP header. 207 FROM:I A FROM parameter containing the IP address I is 208 present in the HIP header. 210 RVS_HMAC An RVS_HMAC parameter containing an HMAC keyed with the 211 appropriate registration key is present in the HIP 212 header. 214 VIA:RVS A VIA_RVS parameter containing the IP address RVS of a 215 rendezvous server is present in the HIP header. 217 3.2. Rendezvous Client Registration 219 Before a rendezvous server starts to relay HIP packets to a 220 rendezvous client, the rendezvous client needs to register with it to 221 receive rendezvous service by using the HIP Registration Extension 222 [I-D.ietf-hip-rfc5203-bis] as illustrated in the following schema: 224 +-----+ +-----+ 225 | | I1 | | 226 | |--------------------------->| | 227 | |<---------------------------| | 228 | I | R1(REG_INFO) | RVS | 229 | | I2(REG_REQ) | | 230 | |--------------------------->| | 231 | |<---------------------------| | 232 | | R2(REG_RES) | | 233 +-----+ +-----+ 235 Rendezvous client registering with a rendezvous server. 237 3.3. Relaying the Base Exchange 239 If a HIP node and one of its rendezvous servers have a rendezvous 240 registration, the rendezvous servers relay inbound I1 packets (that 241 contain one of the client's HITs) by rewriting the IP header. They 242 replace the destination IP address of the I1 packet with one of the 243 IP addresses of the owner of the HIT, i.e., the rendezvous client. 244 They MUST also recompute the IP checksum accordingly. 246 Because of egress filtering on the path from the RVS to the client 247 [RFC2827][RFC3013], a HIP rendezvous server SHOULD replace the source 248 IP address, i.e., the IP address of I, with one of its own IP 249 addresses. The replacement IP address SHOULD be chosen according to 250 relevant IPv4 and IPv6 specifications [RFC1122][RFC3484]. Because 251 this replacement conceals the initiator's IP address, the RVS MUST 252 append a FROM parameter containing the original source IP address of 253 the packet. This FROM parameter MUST be integrity protected by an 254 RVS_HMAC keyed with the corresponding rendezvous registration 255 integrity key [I-D.ietf-hip-rfc5203-bis]. 257 I1(RVS, R, HIT-I, HIT-R 258 I1(I, RVS, HIT-I, HIT-R) +---------+ FROM:I, RVS_HMAC) 259 +----------------------->| |--------------------+ 260 | | RVS | | 261 | | | | 262 | +---------+ | 263 | V 264 +-----+ R1(R, I, HIT-R, HIT-I, VIA:RVS) +-----+ 265 | |<---------------------------------------------| | 266 | | | | 267 | I | I2(I, R, HIT-I, HIT-R) | R | 268 | |--------------------------------------------->| | 269 | |<---------------------------------------------| | 270 +-----+ R2(R, I, HIT-R, HIT-I) +-----+ 272 Rendezvous server rewriting IP addresses. 274 This modification of HIP packets at a rendezvous server can be 275 problematic because the HIP protocol uses integrity checks. Because 276 the I1 does not include HMAC or SIGNATURE parameters, these two end- 277 to-end integrity checks are unaffected by the operation of rendezvous 278 servers. 280 The RVS SHOULD verify the checksum field of an I1 packet before doing 281 any modifications. After modification, it MUST recompute the 282 checksum field using the updated HIP header, which possibly included 283 new FROM and RVS_HMAC parameters, and a pseudo-header containing the 284 updated source and destination IP addresses. This enables the 285 responder to validate the checksum of the I1 packet "as is", without 286 having to parse any FROM parameters. 288 4. Rendezvous Server Extensions 290 This section describes extensions to the HIP Registration Extension 291 [I-D.ietf-hip-rfc5203-bis], allowing a HIP node to register with a 292 rendezvous server for rendezvous service and notify the RVS aware of 293 changes to its current location. It also describes an extension to 294 the HIP specification [I-D.ietf-hip-rfc5201-bis] itself, allowing 295 establishment of HIP associations via one or more HIP rendezvous 296 server(s). 298 4.1. RENDEZVOUS Registration Type 300 This specification defines an additional registration for the HIP 301 Registration Extension [I-D.ietf-hip-rfc5203-bis] that allows 302 registering with a rendezvous server for rendezvous service. 304 Number Registration Type 305 ------ ----------------- 306 1 RENDEZVOUS 308 4.2. Parameter Formats and Processing 310 4.2.1. RVS_HMAC Parameter 312 The RVS_HMAC is a non-critical parameter whose only difference with 313 the HMAC parameter defined in the HIP specification 314 [I-D.ietf-hip-rfc5201-bis] is its "type" code. This change causes it 315 to be located after the FROM parameter (as opposed to the HMAC): 317 Type 65500 318 Length Variable. Length in octets, excluding Type, Length, and 319 Padding. 320 HMAC HMAC computed over the HIP packet, excluding the 321 RVS_HMAC parameter and any following parameters. The 322 HMAC is keyed with the appropriate HIP integrity key 323 (HIP-lg or HIP-gl) established when rendezvous 324 registration happened. The HIP "checksum" field MUST be set 325 to zero, and the HIP header length in the HIP common header 326 MUST be calculated not to cover any excluded parameter 327 when the HMAC is calculated. The size of the 328 HMAC is the natural size of the hash computation 329 output depending on the used hash function. 331 To allow a rendezvous client and its RVS to verify the integrity of 332 packets flowing between them, both SHOULD protect packets with an 333 added RVS_HMAC parameter keyed with the HIP-lg or HIP-gl integrity 334 key established while registration occurred. A valid RVS_HMAC SHOULD 335 be present on every packet flowing between a client and a server and 336 MUST be present when a FROM parameter is processed. 338 4.2.2. FROM Parameter 340 0 1 2 3 341 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 1 342 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 343 | Type | Length | 344 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 345 | | 346 | Address | 347 | | 348 | | 349 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 351 Type 65498 352 Length 16 353 Address An IPv6 address or an IPv4-in-IPv6 format IPv4 address. 355 A rendezvous server MUST add a FROM parameter containing the original 356 source IP address of a HIP packet whenever the source IP address in 357 the IP header is rewritten. If one or more FROM parameters are 358 already present, the new FROM parameter MUST be appended after the 359 existing ones. 361 Whenever an RVS inserts a FROM parameter, it MUST insert an RVS_HMAC 362 protecting the packet integrity, especially the IP address included 363 in the FROM parameter. 365 4.2.3. VIA_RVS Parameter 367 0 1 2 3 368 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 1 369 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 370 | Type | Length | 371 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 372 | | 373 | Address | 374 | | 375 | | 376 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 377 . . . 378 . . . 379 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 380 | | 381 | Address | 382 | | 383 | | 384 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 386 Type 65502 387 Length Variable 388 Address An IPv6 address or an IPv4-in-IPv6 format IPv4 address. 390 After the responder receives a relayed I1 packet, it can begin to 391 send HIP packets addressed to the initiator's IP address, without 392 further assistance from an RVS. For debugging purposes, it MAY 393 include a subset of the IP addresses of its RVSs in some of these 394 packets. When a responder does so, it MUST append a newly created 395 VIA_RVS parameter at the end of the HIP packet. The main goal of 396 using the VIA_RVS parameter is to allow operators to diagnose 397 possible issues encountered while establishing a HIP association via 398 an RVS. 400 4.3. Modified Packets Processing 402 The following subsections describe the differences of processing of 403 I1 and R1 while a rendezvous server is involved in the base exchange. 405 4.3.1. Processing Outgoing I1 Packets 407 An initiator SHOULD NOT send an opportunistic I1 with a NULL 408 destination HIT to an IP address that is known to be a rendezvous 409 server address, unless it wants to establish a HIP association with 410 the rendezvous server itself and does not know its HIT. 412 When an RVS rewrites the source IP address of an I1 packet due to 413 egress filtering, it MUST add a FROM parameter to the I1 that 414 contains the initiator's source IP address. This FROM parameter MUST 415 be protected by an RVS_HMAC keyed with the integrity key established 416 at rendezvous registration. 418 4.3.2. Processing Incoming I1 Packets 420 When a rendezvous server receives an I1 whose destination HIT is not 421 its own, it consults its registration database to find a registration 422 for the rendezvous service established by the HIT owner. If it finds 423 an appropriate registration, it relays the packet to the registered 424 IP address. If it does not find an appropriate registration, it 425 drops the packet. 427 A rendezvous server SHOULD interpret any incoming opportunistic I1 428 (i.e., an I1 with a NULL destination HIT) as an I1 addressed to 429 itself and SHOULD NOT attempt to relay it to one of its clients. 431 When a rendezvous client receives an I1, it MUST validate any present 432 RVS_HMAC parameter. If the RVS_HMAC cannot be verified, the packet 433 SHOULD be dropped. If the RVS_HMAC cannot be verified and a FROM 434 parameter is present, the packet MUST be dropped. 436 A rendezvous client acting as responder SHOULD drop opportunistic I1s 437 that include a FROM parameter, because this indicates that the I1 has 438 been relayed. 440 4.3.3. Processing Outgoing R1 Packets 442 When a responder replies to an I1 relayed via an RVS, it MUST append 443 to the regular R1 header a VIA_RVS parameter containing the IP 444 addresses of the traversed RVSs. 446 4.3.4. Processing Incoming R1 Packets 448 The HIP specification [I-D.ietf-hip-rfc5201-bis] mandates that a 449 system receiving an R1 MUST first check to see if it has sent an I1 450 to the originator of the R1 (i.e., the system is in state I1-SENT). 451 When the R1 is replying to a relayed I1, this check SHOULD be based 452 on HITs only. In case the IP addresses are also checked, then the 453 source IP address MUST be checked against the IP address included in 454 the VIA_RVS parameter. 456 5. Security Considerations 458 This section discusses the known threats introduced by these HIP 459 extensions and the implications on the overall security of HIP. In 460 particular, it argues that the extensions described in this document 461 do not introduce additional threats to the Host Identity Protocol. 463 It is difficult to encompass the whole scope of threats introduced by 464 rendezvous servers because their presence has implications both at 465 the IP and HIP layers. In particular, these extensions might allow 466 for redirection, amplification, and reflection attacks at the IP 467 layer, as well as attacks on the HIP layer itself, for example, man- 468 in-the-middle attacks against the HIP base exchange. 470 If an initiator has a priori knowledge of the responder's host 471 identity when it first contacts the responder via an RVS, it has a 472 means to verify the signatures in the HIP base exchange, which 473 protects against man-in-the-middle attacks. 475 If an initiator does not have a priori knowledge of the responder's 476 host identity (so-called "opportunistic initiators"), it is almost 477 impossible to defend the HIP exchange against these attacks, because 478 the public keys exchanged cannot be authenticated. The only approach 479 would be to mitigate hijacking threats on HIP state by requiring an 480 R1 answering an opportunistic I1 to come from the same IP address 481 that originally sent the I1. This procedure retains a level of 482 security that is equivalent to what exists in the Internet today. 484 However, for reasons of simplicity, this specification does not allow 485 the establishment of a HIP association via a rendezvous server in an 486 opportunistic manner. 488 6. IANA Considerations 490 This section is to be interpreted according to the Guidelines for 491 Writing an IANA Considerations Section in RFCs [RFC2434]. 493 This document updates the IANA Registry for HIP Parameters Types by 494 assigning new HIP Parameter Types values for the new HIP Parameters 495 defined in Section 4.2: 497 o RVS_HMAC (defined in Section 4.2.1) 499 o FROM (defined in Section 4.2.2) 501 o VIA_RVS (defined in Section 4.2.3) 502 This document defines an additional registration for the HIP 503 Registration Extension [I-D.ietf-hip-rfc5203-bis] that allows 504 registering with a rendezvous server for rendezvous service. 506 Number Registration Type 507 ------ ----------------- 508 1 RENDEZVOUS 510 7. Acknowledgments 512 The following people have provided thoughtful and helpful discussions 513 and/or suggestions that have improved this document: Marcus Brunner, 514 Tom Henderson, Miika Komu, Mika Kousa, Pekka Nikander, Justino 515 Santos, Simon Schuetz, Tim Shepard, Kristian Slavov, Martin 516 Stiemerling, and Juergen Quittek. 518 8. References 520 8.1. Normative References 522 [I-D.ietf-hip-rfc5201-bis] Moskowitz, R., Heer, T., Jokela, P., and 523 T. Henderson, "Host Identity Protocol 524 Version 2 (HIPv2)", 525 draft-ietf-hip-rfc5201-bis-09 (work in 526 progress), July 2012. 528 [I-D.ietf-hip-rfc5203-bis] Laganier, J., Koponen, T., and L. Eggert, 529 "Host Identity Protocol (HIP) 530 Registration Extension", 531 draft-ietf-hip-rfc5203-bis-01 (work in 532 progress), March 2011. 534 [I-D.ietf-hip-rfc5205-bis] Laganier, J., "Host Identity Protocol 535 (HIP) Domain Name System (DNS) 536 Extension", draft-ietf-hip-rfc5205-bis-01 537 (work in progress), March 2011. 539 [RFC1122] Braden, R., "Requirements for Internet 540 Hosts - Communication Layers", STD 3, 541 RFC 1122, October 1989. 543 [RFC2119] Bradner, S., "Key words for use in RFCs 544 to Indicate Requirement Levels", BCP 14, 545 RFC 2119, March 1997. 547 [RFC2434] Narten, T. and H. Alvestrand, "Guidelines 548 for Writing an IANA Considerations 549 Section in RFCs", BCP 26, RFC 2434, 550 October 1998. 552 [RFC3484] Draves, R., "Default Address Selection 553 for Internet Protocol version 6 (IPv6)", 554 RFC 3484, February 2003. 556 8.2. Informative References 558 [I-D.ietf-hip-rfc4423-bis] Moskowitz, R., "Host Identity Protocol 559 Architecture", 560 draft-ietf-hip-rfc4423-bis-04 (work in 561 progress), July 2012. 563 [I-D.ietf-hip-rfc5206-bis] Henderson, T., Vogt, C., and J. Arkko, 564 "Host Mobility with the Host Identity 565 Protocol", draft-ietf-hip-rfc5206-bis-04 566 (work in progress), July 2012. 568 [RFC2827] Ferguson, P. and D. Senie, "Network 569 Ingress Filtering: Defeating Denial of 570 Service Attacks which employ IP Source 571 Address Spoofing", BCP 38, RFC 2827, 572 May 2000. 574 [RFC3013] Killalea, T., "Recommended Internet 575 Service Provider Security Services and 576 Procedures", BCP 46, RFC 3013, 577 November 2000. 579 Appendix A. Changes from RFC 5204 581 o Updated HIP references to revised HIP specifications. 583 o Added relaying of UPDATE packets to support double jump mobility 584 scenario. 586 Authors' Addresses 588 Julien Laganier 589 Juniper Networks 590 1094 North Mathilda Avenue 591 Sunnyvale, CA 94089 592 USA 594 Phone: +1 408 936 0385 595 EMail: julien.ietf@gmail.com 596 Lars Eggert 597 NetApp 598 Sonnenallee 1 599 Kirchheim 85551 600 Germany 602 Phone: +49 151 12055791 603 EMail: lars@netapp.com 604 URI: http://eggert.org