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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 intarea Working Group L. Li 3 Internet-Draft Y. Cui 4 Intended status: Standards Track C. Liu 5 Expires: October 22, 2019 J. Wu 6 Tsinghua University 7 F. Baker 9 J. Palet Martinez 10 The IPv6 Company 11 April 20, 2019 13 DHCPv6 Options for Discovery NAT64 Prefixes 14 draft-li-intarea-nat64-prefix-dhcp-option-02 16 Abstract 18 Several IPv6 transition mechanisms require the usage of stateless or 19 stateful translators (commonly named as NAT64) able to allow IP/ICMP 20 communication between IPv4 and IPv6 networks. 22 Those translators are using either a default Well-Known Prefix (WKP), 23 and/or one or several additional Network Specific Prefixes (NSP), 24 which need to be configured into the nodes willing to use the 25 translator. Different translators will likely have different IPv6 26 prefixes, to attract traffic to the correct translator. Thus, an 27 automatic translator prefix discovery method is necessary. 29 This document defines a DHCPv6-based method to inform DHCPv6 clients 30 the set of IPv6 and IPv4 prefixes it serves. This DHCPv6 option can 31 be used by several transition mechanisms such as SIIT, 464XLAT, EAM. 33 Status of This Memo 35 This Internet-Draft is submitted in full conformance with the 36 provisions of BCP 78 and BCP 79. 38 Internet-Drafts are working documents of the Internet Engineering 39 Task Force (IETF). Note that other groups may also distribute 40 working documents as Internet-Drafts. The list of current Internet- 41 Drafts is at https://datatracker.ietf.org/drafts/current/. 43 Internet-Drafts are draft documents valid for a maximum of six months 44 and may be updated, replaced, or obsoleted by other documents at any 45 time. It is inappropriate to use Internet-Drafts as reference 46 material or to cite them other than as "work in progress." 48 This Internet-Draft will expire on October 22, 2019. 50 Copyright Notice 52 Copyright (c) 2019 IETF Trust and the persons identified as the 53 document authors. All rights reserved. 55 This document is subject to BCP 78 and the IETF Trust's Legal 56 Provisions Relating to IETF Documents 57 (https://trustee.ietf.org/license-info) in effect on the date of 58 publication of this document. Please review these documents 59 carefully, as they describe your rights and restrictions with respect 60 to this document. Code Components extracted from this document must 61 include Simplified BSD License text as described in Section 4.e of 62 the Trust Legal Provisions and are provided without warranty as 63 described in the Simplified BSD License. 65 Table of Contents 67 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 68 2. Requirements Language . . . . . . . . . . . . . . . . . . . . 4 69 3. New DHCPv6 Option . . . . . . . . . . . . . . . . . . . . . . 4 70 3.1. NAT64 Prefix List Option Format . . . . . . . . . . . . . 4 71 3.2. NAT64 Prefix Option Format . . . . . . . . . . . . . . . 5 72 4. Client Behavior . . . . . . . . . . . . . . . . . . . . . . . 6 73 5. Message Flow Illustration . . . . . . . . . . . . . . . . . . 7 74 6. Security Considerations . . . . . . . . . . . . . . . . . . . 8 75 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 76 8. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 9 77 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 78 9.1. Normative References . . . . . . . . . . . . . . . . . . 9 79 9.2. Informative References . . . . . . . . . . . . . . . . . 10 80 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11 82 1. Introduction 84 Stateless IP/ICMP Translation (SIIT) [RFC7915], describes the basic 85 translation mechanism (NAT64), which is actually used as the base for 86 many of the related translation protocols. 88 Stateful NAT64 [RFC6146], describes a stateful IPv6 to IPv4 89 translation mechanism, which allows IPv6-only hosts to communicate 90 with IPv4-only servers using unicast UDP, TCP, or ICMP, by means of 91 IPv4 public addresses sharing, among multiple IPv6-only hosts. 92 Unless otherwise stated, references in the rest of this document to 93 NAT64 (function) should be interpreted as to Stateful NAT64. 95 The translation of the packet headers is done using the IP/ICMP 96 translation algorithm defined in [RFC7915] and algorithmically 97 translating the IPv4 addresses to IPv6 addresses and vice versa, 98 following [RFC6052]. 100 464XLAT [RFC6877] describes an architecture that provides IPv4 101 connectivity across a network, or part of it, when it is only 102 natively transporting IPv6. [RFC7849] already suggest the need to 103 support the CLAT function in order to ensure the IPv4 service 104 continuity in IPv6-only cellular deployments. The 464XLAT 105 architecture uses IPv4/IPv6 translation, described in [RFC6144], and 106 standardized in [RFC6052], [RFC7915], and [RFC6146]. In the 464XLAT 107 architecture, the CLAT (customer-side NAT46 translator) must 108 determine which among potentially several PLAT (provider-side NAT64 109 translator) IPv6 prefixes to use in order to send a packet to the 110 PLAT that provides the connectivity to its destination. 112 [RFC7050] describes a mechanism to learn the PLAT-side IPv6 prefix 113 for protocol translation by DNS64 [RFC6147]. Although it supports 114 multiple PLAT-side prefix by responding with multiple AAAA records to 115 a DNS64 query, it does not support mapping IPv4 prefixes to IPv6 116 prefix, which would be required, for example, if one PLAT has 117 connectivity to the general Internet following a default route, 118 another has connectivity to a BGP peer, and a third has connectivity 119 to a network using private addressing [RFC1918]. Therefore, in the 120 scenario with multiple PLATs, [RFC7050] does not directly support 121 destination-based IPv4 routing among PLATs; instead, the DNS64 122 database must contain equivalent information. It also requires the 123 additional deployment of DNS64 service in customer-side networks, 124 which is not required in 464XLAT deployment. Indeed, this scenario, 125 which may become very common in wired access networks, has not even 126 been considered by [RFC7051]. 128 464XLAT is in fact, a very frequent usage case of Stateful NAT64 and 129 actually the predominant one in cellular networks. As indicated in 130 [I-D.ietf-v6ops-nat64-deployment], it is expected that in some 131 scenarios, DNS64 is not used, so mandating the use of [RFC7050] in 132 those cases it is not a sensible approach. 134 Explicit Address Mappings for Stateless IP/ICMP Translation [RFC7757] 135 extends SIIT with an Explicit Address Mapping (EAM) algorithm to 136 facilitate stateless IP/ICMP translation between arbitrary (non- 137 IPv4-translatable) IPv6 endpoints and IPv4. 139 Furthermore, [I-D.ietf-v6ops-nat64-deployment] and 140 [I-D.ietf-v6ops-transition-ipv4aas] show that there is an increasing 141 demand for deployment of NAT64/464XLAT in broadband networks, which 142 may use PCP [RFC7225], to learn the NAT64 prefixes, however is not 143 widely deployed. Instead, DHCPv6/DHCPv6-PD [RFC8415] is the 144 predominant provisioning protocol for broadband CEs (Customer Edge 145 Routers). 147 DHPCv6/DHCPv6-PD is also supported in 3GPP specifications for 148 cellular networks ([RFC6459], [RFC7066], [RFC7849]), even if today is 149 not predominant, but it is expected that the deployment of cellular 150 broadband services will use it, as it is the only standard way to 151 provide shorter prefixes to CEs through the cellular interphase. 153 Finally, even if [RFC7051] discarded DHCPv6 as one of the interesting 154 choices for learning the NAT64 prefix, the deployment considerations 155 have evolved, and in fact there is a new Router Advertising option 156 ([I-D.ietf-6man-ra-pref64]), which provides an alternative in some 157 cases, which is complementary to the one suggested by this document. 159 Consequently, this document proposes a method for the discovery of 160 the NAT64 prefix, based on DHCPv6, which is widely deployed and 161 supported in customer networks. It defines two new DHCPv6 options 162 for use by a DHCPv6 client to discover the NAT64 IPv6 prefix(es). 163 Also, the proposed mechanism can deal with the scenario with multiple 164 independent DNS64 databases supporting separate translators. 166 2. Requirements Language 168 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 169 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 170 "OPTIONAL" in this document are to be interpreted as described in BCP 171 14 [RFC2119] [RFC8174] when, and only when, they appear in all 172 capitals, as shown here. 174 3. New DHCPv6 Option 176 3.1. NAT64 Prefix List Option Format 178 The NAT Prefix List Option is a container for NAT64 Prefix Option(s). 179 A NAT64 Prefix List Option MAY contain multiple NAT64 Prefix Options. 181 The format of the NAT64 Prefix List Option is: 183 0 1 2 3 184 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 1 185 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 186 | OPTION_NAT64_PREFIX_LIST | option-length | 187 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 188 | | 189 + NAT64_PREFIX-options + 190 | | 191 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 193 Figure 1: The format of NAT64 Prefix List option 195 o option-code: OPTION_NAT64_PREFIX_LIST (TBA1) 197 o option-length: length of NAT64_PREFIX-options, specified in 198 octets. 200 o NAT64_PREFIX-options: one or more OPTION_NAT64_PREFIX options. 202 3.2. NAT64 Prefix Option Format 204 The NAT64 Prefix Option is encapsulated in the NAT64 Prefix List 205 Option. This option allows the mapping of destination IPv4 address 206 ranges (contained in the IPv4 Prefix List) to a NAT64 IPv6 prefix. 207 If there is more than one such prefix, each prefix comes in its own 208 option, with its associated IPv4 prefix list. In this way, the 209 DHCPv6 client can select the NAT64 with the corresponding destination 210 IPv4 address. 212 The format of the NAT64 Prefix Option is: 214 0 1 2 3 215 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 1 216 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 217 | OPTION_NAT64_PREFIX | option-length | 218 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 219 | NAT64-Type | NAT64-prelen | 220 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 221 | NAT64-prefix | 222 | (variable length) | 223 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 224 | NAT64-suffix | 225 | (variable length) | 226 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 227 . (optional) . 228 . IPv4 Prefix List (variable length) . 229 . (see Figure 3) . 230 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 232 Figure 2: The format of NAT64 Prefix option 234 0 1 2 3 235 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 1 236 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 237 | IPv4-prelen | IPv4 Prefix (32 bits) | 238 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 239 | (cont.) | IPv4-prelen | IPv4 Prefix (32 bits) | 240 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 241 | IPv4 Prefix (cont.) | ... | 242 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 243 | ... | 244 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 246 Figure 3: The format of IPv4 Prefix List field 248 o option-code: OPTION_NAT64_PREFIX (TBA2) 250 o type-field: NAT64-Type (TBA3) 252 o option-length: 1 + length of NAT64-prefix + length of IPv4 Prefix 253 List, specified in octets. 255 o NAT64-prelen: length of NAT64-prefix. 257 o NAT64-prefix: The NAT64 IPv6 prefix to be used by the DHCPv6 258 client for the IPv6 address synthesis. 260 o NAT64-suffix: The NAT64 suffix to be used by the DHCPv6 client for 261 the IPv6 address synthesis. Not used in case of using the WKP 262 (i.e., 64:ff9b::/96) or any other NSP (Network-Specific Prefix) 263 which a length of 96 bits (/96). 265 o IPv4 Prefix List: This is an optional field. The format of the 266 IPv4 Prefix List is shown in Figure 3. It is a list of zero or 267 more IPv4 Prefixes. Each entry is formed by IPv4-prelen and IPv4 268 Prefix. The total length of the field is 5*number of IPv4 269 prefixes. 271 o IPv4-prelen: the length of the IPv4 Prefix. 273 o IPv4 Prefix: the destination-based IPv4 Prefix. The length is 4 274 octets. 276 4. Client Behavior 278 The client requests the OPTION_NAT64_PREFIX_LIST option using the 279 Option Request option (ORO) in every Solicit, Request, Renew, Rebind, 280 and Information-request message. The NAT64-Type field defines the 281 mechanism being used. If the DHCPv6 server includes the 282 OPTION_NAT64_PREFIX_LIST option in its response, the DHCPv6 client 283 may use the contained NAT64-prefix to translate the destination IPv4 284 address into the destination IPv6 address. 286 When receiving the OPTION_NAT64_PREFIX option with IPv4 Prefix List, 287 the DHCPv6 client MUST record the received IPv6 prefix and the 288 corresponding IPv4 prefixes in IPv4 Prefix List. When receiving the 289 OPTION_NAT64_PREFIX option without IPv4 Prefix List, the DHCPv6 290 client MUST treat the IPv6 prefix and the default IPv4 prefix 291 0.0.0.0/0 as one of the records. 293 If the DHCPv6 client loses contact with the DHCPv6 server, the DHCPv6 294 client SHOULD clear the prefix(es) it learned from the DHCPv6 server. 296 When translating the destination IPv4 address into the destination 297 IPv6 address, DHCPv6 client MUST search an IPv4 routing database 298 using the longest-match-first rule and select the IPv6 prefix 299 offering that IPv4 prefix. 301 5. Message Flow Illustration 303 The figure below shows an example of message flow for a Client 304 learning IPv6 prefixes using DHCPv6. 306 In this example, two IPv6 prefixes are provided by the DHCPv6 server. 307 The first IPv6 prefix is 2001:db8:122:300::/56, the corresponding 308 IPv4 prefixes are 192.0.2.0/24 and 198.51.100.0/24. The second IPv6 309 prefix is 2001:db8:122::/48, the corresponding IPv4 prefix is 310 192.0.2.128/25. 312 When the DHCPv6 client receives the packet with destination IPv4 313 address 192.0.2.1, according to the rule of longest prefix match, the 314 NAT64 with IPv6 prefix 2001:db8:122::/48 is chosen. In the same way, 315 the NAT64 with IPv6 prefix 2001:db8:122::/48 is chosen. 317 +---------------+ +-----------------+ 318 | DHCPv6 Client | | DHCPv6 server | 319 +---------------+ +-----------------+ 320 | DHCPv6 query for IPv6 prefix | 321 |--------------------------------------------------->| 322 | ORO with OPTION_NAT64_PREFIX_LIST | 323 | | 324 | DHCPv6 response with: | 325 | NAT64PREFIX{ | 326 | NAT64-v6-pre = 2001:db8:122:300::/56 | 327 | NAT64-v4-pre = 192.0.2.0/24 | 328 | NAT64-v4-pre = 198.51.100.0/24} | 329 | NAT64PREFIX{ | 330 | NAT64-v6-pre = 2001:db8:122::/48 | 331 | NAT64-v4-pre = 192.0.2.128/25} | 332 |<---------------------------------------------------| 333 | | 334 | 335 | +-----------------+ +-----------------+ 336 | | NAT64 1 | | NAT64 2 | 337 | +-----------------+ +-----------------+ 338 | NAT64-v6-pre = NAT64-v6-pre = 339 | 2001:db8:122:300::/56 2001:db8:122::/48 340 | NAT64-v4-pre = NAT64-v4-pre = 341 | 192.0.2.0/24 192.0.2.128/25 342 | 198.51.100.0/24 | 343 | | | 344 | Dest IPv4 addr: | | 345 | 192.0.2.1 | | 346 | Dest IPv6 addr: | | 347 | 2001:db8:122:300::c000:201 | | 348 |----------------------------->| | 349 | | | 350 | | 351 | Dest IPv4 addr: 192.0.2.193 | 352 | Dest IPv6 addr: 2001:db8:122::c000:2c1 | 353 |--------------------------------------------------->| 355 Figure 4: The example figure of the process procedure 357 6. Security Considerations 359 Considerations for security in this type of environment are primarily 360 around the operation of the DHCPv6 protocol and the databases it 361 uses. 363 In the DHCPv6 server, should the database be compromised, it will 364 deliver incorrect data to its DHCPv6 clients. In the DHCPv6 client, 365 should its database be compromised by attack or polluted by an 366 incorrect DHCPv6 server database, it will route data incorrectly. In 367 both cases, the security of the systems and their databases in an 368 operational matter, not managed by protocol. 370 However, the operation of the DHCPv6 protocol itself is also required 371 to be correct - the server and its clients must recognize valid 372 requests and reject invalid ones. Therefore, DHCPv6 exchanges MUST 373 be secured as described in [RFC8415]. 375 7. IANA Considerations 377 IANA should allocate two DHCPv6 option codes for use by 378 OPTION_V6_PLATPREFIX_LIST and OPTION_V6_PLATPREFIX from the "Option 379 Codes" table. Similarly, a request to IANA for assigning the 380 NAT64-Type field codes. The following initial values are assigned in 381 this document (values are 16-bit unsigned intergers). 383 Name | Value | RFC 384 -----------------+---------+--------- 385 Unspecified | 0x00 | RFC6052 386 SIIT | 0x01 | RFC7915 387 Stateful NAT64 | 0x02 | RFC6146 388 EAM-SIIT | 0x03 | RFC7757 390 8. Acknowledgements 392 The authors will like to recognize the inputs from Tore Anderson in a 393 previous version of this work. Mohamed Boucadair provided very 394 significant inputs. 396 9. References 398 9.1. Normative References 400 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 401 Requirement Levels", BCP 14, RFC 2119, 402 DOI 10.17487/RFC2119, March 1997, 403 . 405 [RFC6877] Mawatari, M., Kawashima, M., and C. Byrne, "464XLAT: 406 Combination of Stateful and Stateless Translation", 407 RFC 6877, DOI 10.17487/RFC6877, April 2013, 408 . 410 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 411 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 412 May 2017, . 414 [RFC8415] Mrugalski, T., Siodelski, M., Volz, B., Yourtchenko, A., 415 Richardson, M., Jiang, S., Lemon, T., and T. Winters, 416 "Dynamic Host Configuration Protocol for IPv6 (DHCPv6)", 417 RFC 8415, DOI 10.17487/RFC8415, November 2018, 418 . 420 9.2. Informative References 422 [I-D.ietf-6man-ra-pref64] 423 Colitti, L., Kline, E., and J. Linkova, "Discovering 424 PREF64 in Router Advertisements", draft-ietf-6man-ra- 425 pref64-00 (work in progress), March 2019. 427 [I-D.ietf-v6ops-nat64-deployment] 428 Palet, J., "Additional NAT64/464XLAT Deployment Guidelines 429 in Operator and Enterprise Networks", draft-ietf-v6ops- 430 nat64-deployment-05 (work in progress), April 2019. 432 [I-D.ietf-v6ops-transition-ipv4aas] 433 Palet, J., Liu, H., and M. Kawashima, "Requirements for 434 IPv6 Customer Edge Routers to Support IPv4 Connectivity 435 as-a-Service", draft-ietf-v6ops-transition-ipv4aas-15 436 (work in progress), January 2019. 438 [RFC1918] Rekhter, Y., Moskowitz, B., Karrenberg, D., de Groot, G., 439 and E. Lear, "Address Allocation for Private Internets", 440 BCP 5, RFC 1918, DOI 10.17487/RFC1918, February 1996, 441 . 443 [RFC6052] Bao, C., Huitema, C., Bagnulo, M., Boucadair, M., and X. 444 Li, "IPv6 Addressing of IPv4/IPv6 Translators", RFC 6052, 445 DOI 10.17487/RFC6052, October 2010, 446 . 448 [RFC6144] Baker, F., Li, X., Bao, C., and K. Yin, "Framework for 449 IPv4/IPv6 Translation", RFC 6144, DOI 10.17487/RFC6144, 450 April 2011, . 452 [RFC6146] Bagnulo, M., Matthews, P., and I. van Beijnum, "Stateful 453 NAT64: Network Address and Protocol Translation from IPv6 454 Clients to IPv4 Servers", RFC 6146, DOI 10.17487/RFC6146, 455 April 2011, . 457 [RFC6147] Bagnulo, M., Sullivan, A., Matthews, P., and I. van 458 Beijnum, "DNS64: DNS Extensions for Network Address 459 Translation from IPv6 Clients to IPv4 Servers", RFC 6147, 460 DOI 10.17487/RFC6147, April 2011, 461 . 463 [RFC6459] Korhonen, J., Ed., Soininen, J., Patil, B., Savolainen, 464 T., Bajko, G., and K. Iisakkila, "IPv6 in 3rd Generation 465 Partnership Project (3GPP) Evolved Packet System (EPS)", 466 RFC 6459, DOI 10.17487/RFC6459, January 2012, 467 . 469 [RFC7050] Savolainen, T., Korhonen, J., and D. Wing, "Discovery of 470 the IPv6 Prefix Used for IPv6 Address Synthesis", 471 RFC 7050, DOI 10.17487/RFC7050, November 2013, 472 . 474 [RFC7051] Korhonen, J., Ed. and T. Savolainen, Ed., "Analysis of 475 Solution Proposals for Hosts to Learn NAT64 Prefix", 476 RFC 7051, DOI 10.17487/RFC7051, November 2013, 477 . 479 [RFC7066] Korhonen, J., Ed., Arkko, J., Ed., Savolainen, T., and S. 480 Krishnan, "IPv6 for Third Generation Partnership Project 481 (3GPP) Cellular Hosts", RFC 7066, DOI 10.17487/RFC7066, 482 November 2013, . 484 [RFC7225] Boucadair, M., "Discovering NAT64 IPv6 Prefixes Using the 485 Port Control Protocol (PCP)", RFC 7225, 486 DOI 10.17487/RFC7225, May 2014, 487 . 489 [RFC7757] Anderson, T. and A. Leiva Popper, "Explicit Address 490 Mappings for Stateless IP/ICMP Translation", RFC 7757, 491 DOI 10.17487/RFC7757, February 2016, 492 . 494 [RFC7849] Binet, D., Boucadair, M., Vizdal, A., Chen, G., Heatley, 495 N., Chandler, R., Michaud, D., Lopez, D., and W. Haeffner, 496 "An IPv6 Profile for 3GPP Mobile Devices", RFC 7849, 497 DOI 10.17487/RFC7849, May 2016, 498 . 500 [RFC7915] Bao, C., Li, X., Baker, F., Anderson, T., and F. Gont, 501 "IP/ICMP Translation Algorithm", RFC 7915, 502 DOI 10.17487/RFC7915, June 2016, 503 . 505 Authors' Addresses 506 Lishan Li 507 Tsinghua University 508 Beijing 100084 509 P.R.China 511 Phone: +86-15201441862 512 Email: lilishan9248@126.com 514 Yong Cui 515 Tsinghua University 516 Beijing 100084 517 P.R.China 519 Phone: +86-10-6260-3059 520 Email: yong@csnet1.cs.tsinghua.edu.cn 522 Cong Liu 523 Tsinghua University 524 Beijing 100084 525 P.R.China 527 Phone: +86-10-6278-5822 528 Email: gnocuil@gmail.com 530 Jianping Wu 531 Tsinghua University 532 Beijing 100084 533 P.R.China 535 Phone: +86-10-6278-5983 536 Email: jianping@cernet.edu.cn 538 Fred Baker 539 Goleta, CA 93117 540 United States 542 Email: fredbaker.ietf@gmail.com 543 Jordi Palet Martinez 544 The IPv6 Company 545 Molino de la Navata, 75 546 La Navata - Galapagar, Madrid 28420 547 Spain 549 Email: jordi.palet@theipv6company.com 550 URI: http://www.theipv6company.com/