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'AGGR') (Obsoleted by RFC 3587) ** Obsolete normative reference: RFC 2373 (ref. 'ADDR') (Obsoleted by RFC 3513) ** Obsolete normative reference: RFC 2462 (ref. 'AUTO') (Obsoleted by RFC 4862) ** Obsolete normative reference: RFC 2461 (ref. 'DISC') (Obsoleted by RFC 4861) -- Possible downref: Non-RFC (?) normative reference: ref. 'EUI64' -- Possible downref: Non-RFC (?) normative reference: ref. 'IANA' ** Obsolete normative reference: RFC 2460 (ref. 'IPV6') (Obsoleted by RFC 8200) -- No information found for draft-ietf-ngtrans-6to4anycsat - is the name correct? -- Possible downref: Normative reference to a draft: ref. '6TO4ANY' == Outdated reference: A later version (-01) exists of draft-ietf-ngtrans-6to4-multicast-00 -- Possible downref: Normative reference to a draft: ref. '6TO4MULTI' ** Obsolete normative reference: RFC 2893 (ref. 'MECH') (Obsoleted by RFC 4213) -- No information found for draft-ietf-ipngwg-default-addr-select - is the name correct? -- Possible downref: Normative reference to a draft: ref. 'SELECT' -- Possible downref: Non-RFC (?) normative reference: ref. 'FBSD' -- Possible downref: Non-RFC (?) normative reference: ref. 'INRIA' ** Downref: Normative reference to an Informational RFC: RFC 2772 (ref. '6BONE') ** Obsolete normative reference: RFC 3041 (ref. 'PRIVACY') (Obsoleted by RFC 4941) ** Obsolete normative reference: RFC 1631 (ref. 'NAT') (Obsoleted by RFC 3022) -- Possible downref: Non-RFC (?) normative reference: ref. 'DISCUSS' Summary: 15 errors (**), 0 flaws (~~), 12 warnings (==), 12 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 1 INTERNET-DRAFT Fred L. Templin 2 SRI International 3 17 May 2001 5 Intra-Site Automatic Tunnel Addressing Protocol (ISATAP) 7 Copyright Notice 9 Placeholder for ISOC copyright. 11 draft-ietf-ngtrans-isatap-01.txt 13 Abstract 15 This document specifies an intra-site automatic tunneling protocol 16 (ISATAP) for connecting IPv6 hosts and routers (nodes) within 17 predominantly IPv4-based networks. This method is based on an IPv6 18 aggregatable global unicast address format (described herein) that 19 embeds the IPv4 address of a node within the EUI-64 format interface 20 identifier. This document assumes that, during the IPv4 to IPv6 co- 21 existence and transition phase, many sites will deploy IPv6 22 incrementally within their IPv4 interior routing domains; especially 23 those sites which have large and complex pre-existing IPv4 24 infrastructures. Within such sites, the address format and methods 25 described in this document will enable IPv6 deployment for nodes that 26 do not share a common data link with an IPv6 gateway for their site. 28 While other works in progress in the NGTRANS working group propose 29 mechanisms for assigning globally-unique IPv6 address prefixes to 30 sites and methods for inter-domain routing between such sites, the 31 approach outlined in this memo enables large-scale incremental 32 deployment of IPv6 for nodes within a site's pre-existing IPv4 33 infrastructure without incurring aggregation scaling issues at the 34 border gateways nor requiring site-wide deployment of special IPv4 35 services such as multicast. The approach proposed by this document 36 supports IPv6 routing within both the site-local and global IPv6 37 routing domains as well as automatic IPv6 in IPv4 tunneling across 38 portions of a site's IPv4 infrastructure which have no native IPv6 39 support. Additionally, this approach supports automatic tunneling 40 within sites which use non globally-unique IPv4 address assignments, 41 such as when Network Address Translation [NAT] is used. 43 Status of this Memo 45 This document is an Internet-Draft and is in full conformance with 46 all provisions of Section 10 of RFC2026. 48 Internet-Drafts are working documents of the Internet Engineering 49 Task Force (IETF), its areas, and its working groups. Note that 50 other groups may also distribute working documents as Internet- 51 Drafts. 53 Internet-Drafts are draft documents valid for a maximum of six months 54 and may be updated, replaced, or obsoleted by other documents at any 55 time. It is inappropriate to use Internet- Drafts as reference 56 material or to cite them other than as "work in progress." 58 The list of current Internet-Drafts can be accessed at 59 http://www.ietf.org/ietf/1id-abstracts.txt 61 The list of Internet-Draft Shadow Directories can be accessed at 62 http://www.ietf.org/shadow.html. 64 1. Introduction 66 The IETF NGTRANS working group anticipates an heterogeneous IPv4/IPv6 67 infrastructure in the near future and thus is chartered to develop 68 mechanisms to support IPv4/IPv6 coexistence and transition toward 69 global IPv6 deployment. For the most part, existing NGTRANS 70 approaches focus on inter-domain routing between IPv6 islands using 71 the existing global IPv4 backbone as transit. But, these islands may 72 themselves comprise complex heterogeneous IPv4/IPv6 networks (e.g. 73 large academic or commercial campus intranets) that require intra- 74 domain IPv4 to IPv6 transition mechanisms and strategies as well. In 75 order to address this requirement, this document presents a simple 76 and scalable approach that enables incremental deployment of IPv6 77 nodes within predominantly IPv4-based intranets. We refer to this 78 approach as the Intra-Site Automatic Tunnel Addressing Protocol, or 79 ISATAP (pronounced: "ice-a-tap"). 81 The ISATAP approach is based on an aggregatable global unicast 82 address format that carries a standard 64-bit IPv6 address prefix 83 [ADDR][AGGR] with a specially-constructed 64-bit EUI-64 Interface 84 Identifier [EUI64]. This address format is fully compatible with 85 both native IPv6 and NGTRANS routing practices (e.g. [6to4],[6BONE]). 86 But, the interface identifier in an ISATAP address employs a special 87 construction (using the IEEE Organizationally Unique Identifier (OUI) 88 reserved by the Internet Assigned Numbers Authority [IANA]) that 89 encapsulates an IPv4 address suitable for automatic IPv6-in-IPv4 tun- 90 neling. Since tunneling occurs only within the site-level prefix of 91 the ISATAP address, the embedded IPv4 address NEED NOT be globally 92 unique; rather, it need only be topologically correct for (and unique 93 within) the context of the site. 95 This approach allows dual-stack nodes that do not share a common 96 datalink with an IPv6 gateway to join the global IPv6 network by 97 automatically tunneling IPv6 messages through the IPv4 routing 98 infrastructure within their site. Two methods for automatic discovery 99 of an off-link IPv6 gateway for ISATAP address autoconfiguration are 100 provided. This approach allows large-scale intra-site deployment 101 without incurring aggregation scaling issues at the border gateways, 102 since only a single IPv6 address prefix is used for the entire site. 103 Finally, this approach supports intranets which use non-globally 104 unique IPv4 addresses, such as when private address allocations 105 [PRIVATE] and/or Network Address Translation [NAT] are used. 107 2. Changes 109 Major changes from version -00 to version -01: 111 - Revised draft to require *different* /64 prefixs for ISATAP 112 addresses and native IPv6 addresses. Thus, a node's ISATAP 113 interface is assigned a /64 prefix that is distinct from the 114 prefixes assigned to any other interfaces attached to the 115 node - be they physical or logical interfaces. This approach 116 eliminates ISATAP-specific sending rules presented in earlier 117 draft versions. 119 - Changed sense of 'u/l' bit in the ISATAP address interface 120 identifier to indicate "local scope", since ISATAP interface 121 identifiers are unique only within the scope of the ISATAP 122 prefix. (See section 4.) 124 Major changes from version personal draft to NGTRANS WG version -00: 126 - Title change to provide higher-level description of field of 127 use addressed by this draft. Removed other extraneous text. 129 - Major new section on automatic discovery of off-link IPv6 routers 130 when IPv6-IPv4 compatibility addresses are used. 132 3. Terminology 134 The terminology of [IPv6] applies to this document. Additionally, the 135 following terms are used extensively throughout this document: 137 ISATAP prefix: 138 Any globally aggregatable 64-bit IPv6 routing prefix (whether from a 139 native IPv6 assigned numbers authority or from a special-purpose numbering 140 scheme such as [6BONE][6TO4]) reserved by a local network administrator 141 specifically for ISATAP purposes. ISATAP prefixes are used to configure 142 ISATAP addresses ONLY; native IPv6 addresses SHOULD NOT be configured 143 using an ISATAP prefix. 145 ISATAP address: 146 An IPv6 address with an ISATAP prefix and having an IPv4 address 147 embedded in the interface identifier in the manner described in 148 section 4 below. 150 ISATAP pseudo-interface: 151 ISATAP encapsulation of IPv6 packets inside IPv4 packets occurs 152 at a point that is logically equivalent to an IPv6 interface, 153 with the link layer being the IPv4 unicast network. This point 154 is referred to as a pseudo-interface. An ISATAP pseudo-interface 155 is assigned an ISATAP address through address autoconfiguration. 157 ISATAP router: 158 An IPv6 router supporting an ISATAP pseudo-interface. It is normally 159 an interior router within an heterogeneous IPv6/IPv4 network. 161 ISATAP host: 162 An IPv6 host which has an ISATAP pseudo-interface. 164 4. ISATAP Address Format 166 In sections 4.1 and 4.2, we will motivate our proposed extensions of 167 the existing IEEE OUI reserved by IANA to support IEEE EUI-64 format 168 addresses. While these proposed extensions are intended support the 169 ISATAP address format, they also provide a flexible framework for 170 future IANA use. Therefore, the extensions proposed in sections 4.1 171 and 4.2 may provide beneficial future use to IANA beyond the scope of 172 ISATAP addresses. We present the ISATAP address format itself in sec- 173 tions 4.3 and 4.4. 175 4.1. IEEE EUI-64 Interface Identifiers in IPv6 Addresses 177 IPv6 aggregatable global and local-use unicast addresses [ADDR] 178 include a 64-bit interface identifier in IEEE EUI-64 format [EUI64], 179 which is specified as the concatenation of a 24-bit company_id value 180 (also known as the OUI) assigned by the IEEE Registration Authority 181 (IEEE/RAC) and a 40-bit extension identifier assigned by the address- 182 ing authority for that OUI. (Normally, the addressing authority is 183 the organization to which the IEEE has allocated the OUI). IEEE EUI- 184 64 interface identifiers are formatted as follows: 186 |0 1|1 3|3 4|4 6| 187 |0 5|6 1|2 7|8 3| 188 +----------------+----------------+----------------+----------------+ 189 |ccccccugcccccccc|ccccccccmmmmmmmm|mmmmmmmmmmmmmmmm|mmmmmmmmmmmmmmmm| 190 +----------------+----------------+----------------+----------------+ 192 Where 'c' are the company-specific bits of the OUI, 'u' is the 193 universal/local bit, 'g' is the individual/group bit and 'm' are the 194 extension identifier bits. (NOTE: [ADDR] specifies that the 'u' bit 195 is inverted from its normal sense in the IEEE context; therefore u=1 196 indicates global scope and u=0 indicates local scope). 198 In order to support encapsulation of legacy IEEE EUI-48 (24-bit) 199 extension identifier values, [EUI64] specifies that the first two 200 octets of the EUI-64 40-bit extension identifier (bits 24 through 39 201 of the EUI-64 address itself) SHALL BE 0xFFFE if the extension iden- 202 tifier encapsulates an EUI-48 value. [EUI64] further specifies that 203 the first two octets of the extension identifier SHALL NOT be 0xFFFF, 204 since this value is reserved by the IEEE/RAC. However, all other 40- 205 bit extension identifier values are available for assignment by the 206 OUI addressing authority. 208 4.2. An EUI-64 Interface Identifier Format for IANA 210 The IANA owns IEEE OUI: 00-00-5E, and [IANA] specifies EUI-48 format 211 (24-bit) interface identifier assignments within that OUI. But, 212 [IANA] does not specify how these legacy EUI-48 assignments will be 213 written in EUI-64 format, nor does it specify a format for future 214 40-bit extension identifier assignments. We propose the following 215 format for EUI-64 addresses within IANA's OUI reservation: 217 |0 2|2 3|3 3|4 6| 218 |0 3|4 1|2 9|0 3| 219 +------------------------+--------+--------+------------------------+ 220 | OUI ("00-00-5E"+u+g) | TYPE | TSE | TSD | 221 +------------------------+--------+--------+------------------------+ 223 Where the fields are: 225 OUI IANA's OUI: 00-00-5E with 'u' and 'g' bits (3 octets) 227 TYPE Type field; indicates how (TSE, TSD) are interpreted (1 octet) 229 TSE Type-Specific Extension (1 octet) 231 TSD Type-Specific Data (3 octets) 233 And the following interpretations are defined based on TYPE: 235 TYPE (TSE, TSD) Interpretation 236 ---- ------------------------- 237 0x00-0xFD RESERVED for future IANA use 238 0xFE (TSE, TSD) together contain an embedded IPv4 address 239 0xFF TSD is interpreted based on TSE as follows: 241 TSE TSD Interpretation 242 --- ------------------ 243 0x00-0xFD RESERVED for future IANA use 244 0xFE TSD contains 24-bit EUI-48 intf id 245 0xFF RESERVED by IEEE/RAC 247 Essentially, if TYPE=0xFE, TSE is treated as an extension of TSD. If 248 TYPE=0xFF, TSE is treated as an extension of TYPE. Other values for 249 TYPE (and hence, other interpretations of TSE, TSD) are reserved for 250 future IANA use. This format conforms to all requirements specified 251 in [EUI64] and supports encapsulation of EUI-48 interface identifiers 252 in the manner described by that document. For example, an existing 253 IANA EUI-48 format multicast address such as: 255 01-00-5E-01-02-03 257 would be written in the IANA EUI-64 format as: 259 01-00-5E-FF-FE-01-02-03 261 But, this proposed format also provides a special TYPE (0xFE) for 262 embedding IPv4 addresses within the IANA 40-bit extension identifier. 263 This special TYPE forms the basis for the ISATAP address format as 264 described in the following sections. 266 4.3. ISATAP Address Construction 268 Using the proposed IANA-specific method for interface identifier con- 269 struction discussed in sections 4.1 and 4.2 (with TYPE=0xFE), and 270 with reference to [ADDR], we can construct an ISATAP address as fol- 271 lows: 273 | 3| 13 | 8 | 24 | 16 | 8 | 8 | 8 | 8 | 32 bits | 274 +--+-----+---+--------+--------+---+---+---+---+---+---+---+----+ 275 |FP| TLA |RES| NLA | SLA | 0x| 0x| 0x| 0x| IPv4 Address | 276 | | ID | | ID | ID | 00| 00| 5E| FE| of Endpoint | 277 +--+-----+---+--------+--------+--------------------------------+ 279 (NOTE: since ISATAP address interface identifiers are interpreted 280 only within the local scope of the /64 ISATAP prefix, we set the u/l 281 bit in the least significant octet of the OUI to '0' to indicate 282 local scope.) 284 By way of example, an existing node with IPv4 address 140.173.129.8 285 might be assigned an IPv6 64-bit prefix of 3FFE:1a05:510:200::/64. We 286 can then construct an ISATAP address for this node as: 288 3FFE:1a05:510:200:0:5EFE:8CAD:8108 290 or (perhaps more appropriately) written as the alternative form for 291 an IPv6 address with embedded IPv4 address found in [ADDR]: 293 3FFE:1a05:510:200:0:5EFE:140.173.129.8 295 Similarly, we can construct the link-local and site-local variants 296 (respectively) of the ISATAP address as: 298 FE80::0:5EFE:140.173.129.8 299 FEC0::200:0:5EFE:140.173.129.8 301 4.4. Advantages 303 By embedding an IPv4 address in the interface identifier portion of 304 an IPv6 address as described in section 4.3, we can construct aggre- 305 gatable global unicast IPv6 addresses that can either be routed glo- 306 bally via the IPv6 infrastructure or automatically tunneled locally 307 across portions of a site's IPv4 infrastructure which have no native 308 IPv6 support. Additionally, a node with an ISATAP address could act 309 as a gateway for nodes with native IPv6 addresses with which it 310 shares a common physical link, since the ISATAP node could automati- 311 cally tunnel messages across a site's IPv4 domain on behalf of the 312 native IPv6 nodes. An example would be deployment of IPv6 on some 313 subset of the hosts attached to a workgroup's LAN. In this case, one 314 host could configure an ISATAP address and act as a gateway for other 315 hosts on the LAN which use native IPv6 addresses. 317 An additional advantage for our proposed method of embedding an IPv4 318 address in the interface identifier portion of an IPv6 address not 319 found in other approaches such as [6TO4] is that large numbers of 320 ISATAP addresses could be assigned within a common IPv6 routing pre- 321 fix, thus providing maximal aggregation at the border gateways. For 322 example, the single 64-bit IPv6 prefix: 324 3FFE:1a05:510:2412::/64 326 could include literally millions of nodes with ISATAP addresses. 328 This feature would allow a "sparse mode" IPv6 deployment such as the 329 deployment of sparse populations of IPv6 hosts on large numbers of 330 independent links throughout a large corporate Intranet. 332 A final important advantage is that this method supports both sites 333 that use globally unique IPv4 address assignments and those that use 334 non-globally unique IPv4 addresses, such as when private address 335 assignments and/or Network Address Translation are used. By way of 336 analogy to the US Postal system, inter-domain transition approaches 337 such as [6TO4] provide means for routing messages "cross-country" to 338 the "street address" of a distant site while the approach outlined in 339 this document provides localized routing information to reach a 340 specific (mailstop, apartment number, post office box, etc) WITHIN 341 that site. Thus, the site-level routing information need not have 342 relevance outside the scope of that site. 344 5. ISATAP Deployment Considerations 346 ISATAP addresses should only be used by nodes which do not share a 347 common datalink with a native IPv6 router. At least one ISATAP router 348 must be configured within the site which advertises an 349 administratively- assigned ISATAP prefix in response to an Rtsol mes- 350 sage from an off-link host. Such off-link hosts will configure an 351 ISATAP pseudo-interface and assign it an address using the ISATAP 352 prefix it receives in an Rtadv message solicited from an ISATAP 353 router. 355 Following ISATAP address configuration, ISATAP hosts automatically 356 and transparently communicate the IPv4 address of their *own* end of 357 the ISATAP tunnel to any ISATAP host or router which uses the same 358 ISATAP prefix. While nodes may optionally use stateful configuration 359 to set an ISATAP prefix and a "default" route that points to an ISA- 360 TAP router, a greatly preferred alternative is to provide for 361 automatic intra-site IPv6 router discovery and stateless address 362 autoconfiguration [DISCUSS]. The following section presents a means 363 for the automatic discovery of ISATAP routers. 365 5.1. Automatic Discovery of ISATAP Routers 367 As described in [AUTO], a node that does not share a common multiple 368 access datalink with an IPv6 router will NOT receive unsolicited 369 Router Advertisements (Rtadv's), nor will Router Solicitations 370 (Rtsol's) from that node reach an IPv6 router on the local link. But, 371 the node may still be able to connect to the global IPv6 Internet if 372 an ISATAP router for the site exists. Hence, a means for ISATAP 373 router discovery is required. We present the following procedure for 374 a node to initiate ISATAP router discovery (and for an ISATAP router 375 to respond) when an on-link IPv6 router is not available: 377 - The node constructs an ISATAP link local address for itself 378 (as described in section 4.) as: 380 FE80::0:5EFE:V4ADDR_NODE 382 - The node discovers the IPv4 address for an ISATAP router 383 as: V4ADDR_RTR (**) 385 - The node sends an Rtsol to the IPv6 "all-routers-multicast" address 386 tunneled through the IPv4 infrastructure to the ISATAP router's 387 IPv4 address. The addresses used in the IPv6 and IPv4 headers are: 389 ipv6_src: FE80::0:5EFE:V4ADDR_NODE 390 ipv6_dst: FF02::2 391 ipv4_src: V4ADDR_NODE 392 ipv4_dst: V4ADDR_RTR 394 - Upon receiving the tunneled Rtsol, the ISATAP router sends 395 a unicast Rtadv to the unicast address of the node which sent the 396 Rtsol; again, by tunneling the Rtadv through IPv4. The addresses 397 used in the IPv6 and IPv4 headers are: 399 ipv6_src: FE80::0:5EFE:V4ADDR_RTR 400 ipv6_dst: FE80::0:5EFE:V4ADDR_NODE 401 ipv4_src: V4ADDR_RTR 402 ipv4_dst: V4ADDR_NODE 404 - Upon receiving the Rtsol, the originating node performs address 405 autoconfiguration as described in [AUTO] and constructs: 407 - a fully-qualified ISATAP address for use as the source address 408 for an ISATAP pseudo-interface 410 - a default route that points to the ISATAP router 412 Note (**) that the above procedure assumes a means for discovering 413 V4ADDR_RTR. We present two alternative methods for the automatic 414 discovery of V4ADDR_RTR: 416 5.2. DNS Well-Known Service Name 418 The first method for discovering V4ADDR_RTR employs a new DNS Well- 419 Known Service (WKS) name [DNS1,DNS2]. With the establishment of a new 420 well-known service name (e.g. "ISATAPGW"), administrators could pub- 421 lish the IPv4 address of a gateway which implementations could use to 422 discover V4ADDR_RTR. This method has the advantage that it can be 423 deployed immediately using existing mechanisms. However, it requires 424 name service lookups and may not always provide the optimum 425 V4ADDR_RTR resolution for isolated hosts if multiple ISATAP routers 426 are available. 428 5.3. IPv4 Anycast for ISATAP routers 430 [6TO4ANY] proposes an IPv4 anycast prefix for 6to4 relay routers. 431 The proposal suggests an IPv4 prefix assignment 'x.x.x.0/nn' ('nn' is 432 currently proposed as 16) where the single address 'x.x.x.1' is 433 assigned as the "6to4 IPv6 relay anycast address". We propose analo- 434 gous assignments for the purpose of an "ISATAP router anycast 435 address". (Whether the reservation of a second /32 assignment from 436 the 6to4 IPv4 anycast prefix proposed in [6TO4ANY] would be possible, 437 or a separate prefix assignment would be required is a matter of 438 debate and TBD.) 440 ISATAP routers would advertise the ISATAP router anycast prefix via 441 the intra-domain IPv4 routing infrastructure. Isolated IPv6 nodes 442 would then use the ISATAP router anycast address as the V4ADDR_RTR 443 IPv4 destination for off-link Rtsol's. This approach has the signifi- 444 cant advantages that: 446 - implementations could hard-code the well-known ISATAP 447 anycast address, thus avoiding service discovery via DNS 449 - an optimum path to an ISATAP router would be ensured 450 by intra-domain IPv4 routing 452 As described above, the IPv4 anycast method for locating ISATAP 453 routers provides significant functional advantages over the DNS 454 approach, while the DNS approach can be implemented immediately pend- 455 ing the registration of a WKS name with IANA. While either method 456 will work, the decision of which to push for standardization is TBD 457 pending discussion at upcoming NGTRANS WG meetings. 459 6. Sending Rules and Routing Considerations 461 Since each node will be assigned an ISATAP prefix which is adminis- 462 tratively reserved for use ONLY by ISATAP nodes, no special sending 463 rules are needed. In particular, correspondent nodes that share a 464 common ISATAP prefix will always exchange messages using their ISATAP 465 pseudo-interfaces, whereas nodes that do not share a common ISATAP 466 prefix will always exchange messages via standard IPv6 routing. When 467 sending a message on an ISATAP pseudo-interface, an implementation 468 SHOULD verify that the IPv6 destination address employs the ISATAP 469 address construction rules described in section 4 in order to detect 470 mis-configured addresses. No other sending rules are necessary. 472 7. Address Selection 474 No special address selection rules are necessary. 476 8. Automatic Deprecation 478 ISATAP addresses are intended for use only by nodes which do not 479 receive native IPv6 Rtadv's due to not sharing a common datalink with 480 an IPv6 router. When native IPv6 Rtadv's become available (such as 481 when an IPv6 router is deployed on a node's datalink), the node 482 should construct a non-ISATAP aggregatable global IPv6 unicast 483 address using address auto-configuration [AUTO] for a non-ISATAP IPv6 484 prefix discovered through normal means [DISC]. After the node's 485 native IPv6 address is populated in the DNS, the node should eventu- 486 ally cease sending Rtsol's to the ISATAP router and discontinue use 487 of its ISATAP pseudo-interface. In this way, ISATAP addresses will 488 gradually (and automatically) disappear as IPv6 routers are widely 489 deployed within sites. 491 9. Multicast Considerations 493 Other works in progress [6TO4MULTI] are currently investigating mul- 494 ticast addressing issues for [6TO4]. The address format discussed in 495 this document is expected to be compatible with those emerging 496 approaches. 498 10. IANA considerations 500 In order to support the EUI-64 address form described in this docu- 501 ment, we propose that IANA adopt the EUI-64 Interface Identifier for- 502 mat specified in section 4.2 for the existing 00-00-5E OUI owned by 503 IANA. No other actions are required by the IANA. 505 11. Security considerations 507 The ISATAP address format does not support privacy extensions for 508 stateless address autoconfiguration [PRIVACY]. However, such privacy 509 extensions are intended primarily to avoid revealing one's MAC 510 address, and the ISATAP address format described in this document 511 accomplishes this same goal. 513 Additional security issues are called out in [6TO4] and probably 514 apply here as well. 516 12. Implementation status 518 The author has implemented the mechanisms described in this draft 519 through modifications to the FreeBSD 3.2-RELEASE [FBSD] operating 520 system with the INRIA [INRIA] IPv6 distribution. A Linux implementa- 521 tion is planned for the June, 2001 timeframe. 523 Additionally, Windows XP RC1 will implement elements of the mechanism 524 proposed in this paper. 526 Acknowledgements 528 The original ideas presented in this draft were derived from SRI con- 529 tractual work. The author recognizes that ideas similar to those in 530 this document may have already been presented by others and wishes to 531 acknowledge any other such authors. The author also wishes to ack- 532 nowledge the government contract administrators who sponsored the 533 projects from which these works derived as well as his SRI colleagues 534 with whom he has discussed and reviewed this work, including Monica 535 Farah-Stapleton, Dr. Mike Frankel, J. Peter Marcotullio, Lou Rodri- 536 guez, and Dr. Ambatipudi Sastry. 538 The author acknowledges valuable input from numerous members of the 539 NGTRANS community which has helped guide the direction of the draft. 540 The list of contributors is too long to enumerate, but the input from 541 the community has been vital to the draft's evolution. Alain Durand 542 deserves special mention for contributing the title of this draft and 543 the ISATAP acronym. 545 The author finally wishes to provide special acknowledgement to Dave 546 Thaler, Art Shelest, Richard Draves, and others at Microsoft Research 547 for their ideas on automatic discovery of off-link IPv6 routers. Much 548 of the text in section on deployment considerations derives directly 549 from discussions with Dave, Art, Rich and others. 551 References 553 [AGGR] Hinden., R, O'Dell, M., and Deering, S., "An IPv6 554 Aggregatable Global Unicast Address Format", 555 RFC 2374, July 1998. 557 [ADDR] Hinden, R., and S. Deering, "IP Version 6 Addressing 558 Architecture", RFC 2373, July 1998. 560 [AUTO] Thomson, S., and T. Narten, "IPv6 Stateless Address 561 Autoconfiguration", RFC 2462, December 1998. 563 [DISC] Narten, T., Nordmark, E., and W. Simpson, "Neighbor 564 Discovery for IP Version 6 (IPv6)", RFC 2461, 565 December 1998. 567 [DNS1] Mockapetris, P. "Domain names - concepts and facilities", 568 STD 13, RFC 1034, November 1987. 570 [DNS2] Mockapetris, P. "Domain names - Implementation and Specif- 571 ication", 572 STD 13, RFC 1035, November 1987. 574 [DNSSRV] Gulbrandsen, A., Vixie, P., and L. Esibov, "A DNS RR for 575 specifying the location of services (DNS SRV)", RFC 2782, 576 February 2000. 578 [EUI64] IEEE, "Guidelines for 64-bit Global Identifier (EUI-64) 579 Registration Authority", 580 http://standards.ieee.org/regauth/oui/tutorials/EUI64.html, 581 March 1997 583 [IANA] Reynolds, J., and J. Postel, "Assigned Numbers", STD 2, 584 USC/Information Sciences Institute, October 1994. 586 [IPV4] Postel, J., "Internet Protocol", RFC 791 588 [IPV6] Deering, S., and R. Hinden, "Internet Protocol, Version 6 589 (IPv6) Specification", RFC 2460 591 [6TO4] Carpenter, B., and K. Moore, "Connection of IPv6 Domains 592 via IPv4 Clouds", RFC 3056, February 2001. 594 [6TO4ANY] Huitema, C., "An anycast prefix for 6to4 relay routers", 595 draft-ietf-ngtrans-6to4anycsat-02.txt (work in progress) 597 [6TO4MULTI] Thaler, D., "Support for Multicsat over 6to4 Networks", 598 draft-ietf-ngtrans-6to4-multicast-00.txt (work in pro- 599 gress) 601 [MECH] Gilligan, R., and E. Nordmark, "Transition Mechanisms for 602 IPv6 Hosts and Routers", RFC 2893, August 2000. 604 [SELECT] Draves, R., Default Address Selection for IPv6, draft- 605 ietf- 606 ipngwg-default-addr-select-00.txt (work in progress) 608 [FBSD] http://www.freebsd.org 610 [INRIA] ftp://ftp.inria.fr/network/ipv6/ 612 [6BONE] Rockell, R., and R. Fink, RFC 2772, February 2000. 614 [PRIVATE] Rekhter, Y., Moskowitz, B., Karrenberg, D., de Groot, G. 615 J., 616 and E. Lear, "Address Allocation for Private Internets", 617 RFC 1918, February 1996. 619 [PRIVACY] Narten, T., R. Draves, "Privacy Extensions for Stateless 620 Address 621 Autoconfiguration in IPv6", RFC 3041, January 2001. 623 [NAT] Egevang, K., and P. Francis, "The IP Network Address 624 Translator (NAT)", RFC 1631, May 1994. 626 [DISCUSS] private discussions with Dave Thaler, Art Shelest, et al. 628 Authors Addresses 630 Fred L. Templin 631 SRI International 632 333 Ravenswood Ave. 633 Menlo Park, CA 94025, USA 635 Email: templin@erg.sri.com 637 Intellectual Property 639 PLACEHOLDER for full IETF IPR Statement if needed. 641 Full Copyright Statement 643 PLACEHOLDER for full ISOC copyright Statement if needed.