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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 MIP4 K. Leung 3 Internet-Draft G. Dommety 4 Intended status: Standards Track Cisco Systems 5 Expires: September 12, 2008 V. Narayanan 6 Qualcomm, Inc. 7 A. Petrescu 8 Motorola 9 March 11, 2008 11 Network Mobility (NEMO) Extensions for Mobile IPv4 12 draft-ietf-mip4-nemo-v4-base-11.txt 14 Status of this Memo 16 By submitting this Internet-Draft, each author represents that any 17 applicable patent or other IPR claims of which he or she is aware 18 have been or will be disclosed, and any of which he or she becomes 19 aware will be disclosed, in accordance with Section 6 of BCP 79. 21 Internet-Drafts are working documents of the Internet Engineering 22 Task Force (IETF), its areas, and its working groups. Note that 23 other groups may also distribute working documents as Internet- 24 Drafts. 26 Internet-Drafts are draft documents valid for a maximum of six months 27 and may be updated, replaced, or obsoleted by other documents at any 28 time. It is inappropriate to use Internet-Drafts as reference 29 material or to cite them other than as "work in progress." 31 The list of current Internet-Drafts can be accessed at 32 http://www.ietf.org/ietf/1id-abstracts.txt. 34 The list of Internet-Draft Shadow Directories can be accessed at 35 http://www.ietf.org/shadow.html. 37 This Internet-Draft will expire on September 12, 2008. 39 Copyright Notice 41 Copyright (C) The IETF Trust (2008). 43 Abstract 45 This document describes a protocol for supporting Mobile Networks 46 between a Mobile Router and a Home Agent by extending the Mobile IPv4 47 protocol. A Mobile Router is responsible for the mobility of one or 48 more network segments or subnets moving together. The Mobile Router 49 hides its mobility from the nodes on the mobile network. The nodes 50 on the Mobile Network may be fixed in relationship to the Mobile 51 Router and may not have any mobility function. 53 Extensions to Mobile IPv4 are introduced to support Mobile Networks. 55 Table of Contents 57 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 58 1.1. Examples of Mobile Networks . . . . . . . . . . . . . . . 3 59 1.2. Overview of Protocol . . . . . . . . . . . . . . . . . . . 4 60 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 6 61 3. Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 7 62 4. Mobile Network Extensions . . . . . . . . . . . . . . . . . . 8 63 4.1. Mobile Network Request Extension . . . . . . . . . . . . . 8 64 4.2. Mobile Network Acknowledgement Extension . . . . . . . . . 9 65 5. Mobile Router Operation . . . . . . . . . . . . . . . . . . . 11 66 5.1. Error Processing . . . . . . . . . . . . . . . . . . . . . 12 67 5.2. Mobile Router Management . . . . . . . . . . . . . . . . . 12 68 6. Home Agent Operation . . . . . . . . . . . . . . . . . . . . . 13 69 6.1. Summary . . . . . . . . . . . . . . . . . . . . . . . . . 13 70 6.2. Data Structures . . . . . . . . . . . . . . . . . . . . . 14 71 6.2.1. Registration Table . . . . . . . . . . . . . . . . . . 14 72 6.2.2. Prefix Table . . . . . . . . . . . . . . . . . . . . . 14 73 6.3. Mobile Network Prefix Registration . . . . . . . . . . . . 14 74 6.4. Advertising Mobile Network Reachability . . . . . . . . . 16 75 6.5. Establishment of Bi-directional Tunnel . . . . . . . . . . 16 76 6.6. Sending Registration Replies . . . . . . . . . . . . . . . 17 77 6.7. Mobile Network Prefix De-registration . . . . . . . . . . 17 78 7. Data Forwarding Operation . . . . . . . . . . . . . . . . . . 17 79 8. Nested Mobile Networks . . . . . . . . . . . . . . . . . . . . 18 80 9. Routing Protocol between Mobile Router and Home Agent . . . . 18 81 10. Security Considerations . . . . . . . . . . . . . . . . . . . 19 82 10.1. Security when Dynamic Routing Protocol is Used . . . . . . 20 83 11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 20 84 12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 22 85 13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 23 86 13.1. Normative References . . . . . . . . . . . . . . . . . . . 23 87 13.2. Informative References . . . . . . . . . . . . . . . . . . 24 88 Appendix A. ChangeLog . . . . . . . . . . . . . . . . . . . . . . 24 89 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 28 90 Intellectual Property and Copyright Statements . . . . . . . . . . 30 92 1. Introduction 94 This document describes network mobility extensions to the Mobile 95 IPv4 protocol. The goal of introducing these extensions is to 96 acommodate mobility scenarios where groups of hosts and routers move 97 homogeneously (as a whole). It is required that all hosts and 98 routers in a mobile network be able to run applications connecting to 99 the Internet, and to be reachable from the Internet. 101 For details regarding terminology related to network mobility (NEMO), 102 the gentle reader is suggested a quick read of RFC 4885 [RFC4885]. 104 1.1. Examples of Mobile Networks 106 A mobile network links together a set of hosts and routers. 107 Connecting this mobile network to the Internet is ensured at two 108 levels: first, a Mobile Router is connected on one side to the Mobile 109 Network and on another side to a wireless access system; second, a 110 Home Agent placed on the home link manages traffic between the 111 Correspondent Node and a Local Fixed Node (LFN, a node in the mobile 112 network) by means of encapsulating traffic. 114 A scenario of applicability for this mobile network is described 115 next. A mobile network is formed by a wireless-enabled Personal 116 Digital Assistant (PDA) and a portable photographic camera, linked 117 together by Bluetooth wireless link-layer technology. This is 118 sometimes referred to as a Personal Area Network (PAN). In the 119 illustration below one can notice the PDA playing the role of a 120 Mobile Router and the camera the role of Local Fixed Node: 122 ---- 123 | HA | 124 ---- -------- 125 | / \ ---- 126 -+--------| Internet |---------| CN | 127 \ / ---- 128 -------- 129 / \ 130 / \ 131 / \ 132 ---- ---- 133 | AR | | AR | 134 ---- ---- 135 |cellular |cellular 137 / |cellular 138 | ---- ---- 139 Mobile | | MR | |LFN | ---movement--> 140 Network < ---- ---- 141 | | | 142 | -+-----------+- 143 \ Bluetooth 145 The camera (Local Fixed Node) uploads photographic content to a 146 Correspondent Node (CN) server. When the mobile network moves away, 147 the Mobile Router serving the mobile network changes its point of 148 attachment from one cellular access (Access Router) to another, 149 obtaining a new Care-of Address. The Home Agent (HA) encapsulates 150 application traffic for CN and LFN. 152 Whereas the illustration above is a very simple instantiation of the 153 applicability of Mobile IP-based mobile networks, more complex mobile 154 networks are easily acommodated by the Mobile IPv4 extensions 155 presented in this document (NEMOv4). For example, laptop computers 156 used by passengers in a bus, train, ship or in a plane should all be 157 considered as forming mobile networks, as long as they move together 158 (homogeneously). 160 1.2. Overview of Protocol 162 As introduced previously, this document presents extensions to the 163 Mobile IPv4 protocol. The entities sending and receiving these 164 extensions are the Mobile Router and the Home Agent. The Local Fixed 165 Node is relieved from running Mobile IP software and, although it 166 moves (together with the mobile network), its IP stack is not seing 167 any change in addressing. 169 Mobility for the entire Mobile Network is supported by the Mobile 170 Router registering its current point of attachment (Care-of Address) 171 to its Home Agent: Mobile Router sends an extended Registration 172 Request to Home Agent which returns an extended Registration Reply. 173 This signaling sets up the tunnel between the two entities, as 174 illustrated in the following figure: 176 LFN MR HA CN 177 | | | | 178 | | Extended Registration | | 179 | |---------------------->| | 180 | | Request | | 181 | | | | 182 | | | | 183 | | Extended Registration | | 184 | |<----------------------| | 185 | | Reply | | 186 | | | | 187 |<--------o=======================o-------->| 188 | | Encapsulated | | 189 | | Application Traffic | | 190 | | | | 192 The prefix(es) used within a Mobile Network (either implicitly 193 configured on the Home Agent or explicitly identified by the Mobile 194 Router in the Registration Request) is/are advertised by the Home 195 Agent for route propagation in the home network. Traffic to and from 196 nodes in the Mobile Network are tunelled by the Home Agent to the 197 Mobile Router, and vice versa. Though packets from a Local Fixed 198 Node placed in the Mobile Network can be forwarded by the Mobile 199 Router directly without tunneling (if reverse tunneling were not 200 used) these packets will be dropped if ingress filtering is turned on 201 at the Access Router. 203 Extensively relating to Mobile IPv4 RFC 3344 [RFC3344], this 204 specification addresses mainly the co-located Care-of Address mode. 205 Foreign Agent Care-of Address mode (with 'legacy' Foreign Agents, 206 RFC 3344 [RFC3344]) are supported but without optimization, double 207 encapsulation being used. For an optimization of this mode, the 208 gentle reader is directed to an extension document 209 [I-D.ietf-mip4-nemov4-fa]. 211 Compared to Mobile IPv4, this document specifies an additional tunnel 212 between a Mobile Router's Home Address and the Home Agent. This 213 tunnel is encapsulated within the normal tunnel between the Care-of 214 Address (CoA) and Home Agent. In Foreign Agent CoA mode, the tunnel 215 between the Mobile Router and Home Agent is needed to allow the 216 Foreign Agent to direct the decapsulated packet to the proper 217 visiting Mobile Router. However, in Collocated CoA mode, the 218 additional tunnel is not essential and could be eliminated because 219 the Mobile Router is the recipient of the encapsulated packets for 220 the Mobile Network; a proposal for this feature is in a further 221 extending document [I-D.ietf-mip4-nemov4-fa]. 223 All traffic between the nodes in the Mobile Network and Correspondent 224 Nodes passes through the Home Agent. This document does not touch on 225 aspects related to route optimization of this traffic. 227 A similar protocol has been documented in RFC 3963 [RFC3963] for 228 supporting IPv6 mobile networks with Mobile IPv6 extensions. 230 Multihoming for Mobile Routers is outside the scope of this document. 232 2. Terminology 234 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 235 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 236 document are to be interpreted as described in RFC 2119 [RFC2119]. 238 Terminology for Mobile IPv4 mobility support is defined in RFC 3344 239 [RFC3344]. Terminology for network mobility support (NEMO), from an 240 IPv6 perspective, is described in RFC 4885 [RFC4885]. In addition, 241 this document defines the following terms for NEMOv4. 243 Mobile Router 245 RFC 3344 [RFC3344] defines a Mobile Router as a mobile node 246 that can be a router that is responsible for the mobility of 247 one or more entire networks moving together, perhaps on an 248 airplane, a ship, a train, an automobile, a bicycle, or a 249 kayak. 251 Mobile Network Prefix 253 The network prefix of the subnet delegated to a Mobile Router 254 as the Mobile Network. 256 Prefix Table 258 A list of Mobile Network Prefixes indexed by the Home Address 259 of a Mobile Router. The Home Agent manages and uses Prefix 260 Table to determine which Mobile Network Prefixes belong to a 261 particular Mobile Router. 263 Local Fixed Node 265 RFC 4885 [RFC4885] defines a Local Fixed Node (LFN) to be a 266 fixed node belonging to the mobile network and unable to 267 change its point of attachment. This definition should not 268 be confused with "Long, Fat Network, LFN" of RFC 1323 269 [RFC1323], at least because this latter is pronounced 270 "elephan(t)" whereas a NEMO LFN is distinctively pronounced 271 "elefen". 273 3. Requirements 275 Although the original Mobile IPv4 specifications stated that Mobile 276 Networks can be supported by the Mobile Router and Home Agent using 277 static configuration or running a routing protocol (see Section 4.5 278 of RFC 3344 [RFC3344]), there is no solution for explicit 279 registration of the Mobile Networks served by the Mobile Router. A 280 solution needs to provide the Home Agent a means to ensure that a 281 Mobile Router claiming a certain Mobile Network Prefix is authorized 282 to do so. A solution would also expose the Mobile Network Prefixes 283 (and potentially other subnet-relevant information) in the exchanged 284 messages, to aid in network debugging. 286 The following requirements for Mobile Network support are enumerated: 288 o A Mobile Router should be able to operate in explicit or implicit 289 mode. A Mobile Router may explicitly inform the Home Agent which 290 Mobile Network(s) need to be propagated via a routing protocol. A 291 Mobile Router may also function in implicit mode, where the Home 292 Agent may learn the mobile networks through other means, such as 293 from the AAA server, via pre-configuration, or via a dynamic 294 routing protocol. 296 o The Mobile Network should be supported using Foreign Agents that 297 are compliant to RFC 3344 [RFC3344] without any changes ('legacy' 298 Foreign Agents). 300 o The mobile network should allow Fixed Nodes, Mobile Nodes, or 301 Mobile Routers to be on it. 303 o The Local Fixed Nodes on a mobile network should be able to 304 execute their sessions without running themselves Mobile IP 305 stacks. The Mobile Router managing the LFNs' mobile network is 306 'hiding' mobility events like the changes of the Care-of Address 307 from the Local Fixed Nodes in that mobile network. 309 4. Mobile Network Extensions 311 4.1. Mobile Network Request Extension 313 For Explicit Mode, the Mobile Router informs the Home Agent about the 314 Mobile Network Prefixes during registration. The Registration 315 Request contains zero, one or several Mobile Network Request 316 extensions in addition to any other extensions defined by or in the 317 context of RFC 3344 [RFC3344]. When several Mobile Networks are 318 needed to be registered, each is included in a separate Mobile 319 Network Request extension, with its own Type, Length, Sub-Type, 320 Prefix Length and Prefix. A Mobile Network Request extension is 321 encoded in Type-Length-Value (TLV) format and respects the following 322 ordering: 324 0 1 2 3 325 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 1 326 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 327 | Type | Length | Sub-Type | Prefix Length | 328 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 329 | Prefix | 330 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 332 Type: 334 Mobile Network Extension (skippable type range to be assigned 335 by IANA). 337 Length: 339 Decimal 6. 341 Sub-Type: 343 TBA (Mobile Network Request) 345 Prefix Length: 347 8-bit unsigned integer indicating the number of leftmost bits 348 covering the network part of the address contained in the 349 Prefix field. 351 Prefix: 353 32-bit unsigned integer in network byte-order containing an 354 IPv4 address whose leftmost Prefix Length bits make up the 355 Mobile Network Prefix. 357 4.2. Mobile Network Acknowledgement Extension 359 The Registration Reply contains zero, one or several Mobile Network 360 Acknowledgement extensions in addition to any other extensions 361 defined by or in the context of RFC 3344 [RFC3344]. For Implicit 362 Mode, the Mobile Network Acknowledgement informs the Mobile Router 363 the prefixes for which the Home Agent sets up forwarding with respect 364 to this Mobile Router. Policies such as permitting only traffic from 365 these Mobile Networks to be tunneled to the Home Agent may be applied 366 by the Mobile Router. For Explicit Mode, when several Mobile 367 Networks are needed to be acknowledged explicitly, each is included 368 in a separate Mobile Network Acknowledgement extension, with its own 369 Type, Sub-Type, Length, Prefix and Prefix Length fields. At least 370 one Mobile Network Acknowledgement extension MUST be in a successful 371 Registration Reply to indicate to the Mobile Router that the Mobile 372 Network Request extension was processed, thereby not skipped by the 373 Home Agent. 375 A Registration Reply may contain any non-zero number of Explicit Mode 376 and Implicit Mode Acknowledgements sub-types. Both sub-types can be 377 present in a single Registration Reply. A Mobile Network 378 Acknowledgement extension is encoded in Type-Length-Value (TLV) 379 format. When the registration is denied with Code HA_MOBNET_ERROR 380 (Code field in the Registration Reply), the Code field in the 381 included Mobile Network Extension provides the reason for the 382 failure. 384 0 1 2 3 385 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 1 386 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 387 | Type | Length | Sub-Type | Code | 388 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 389 | Prefix Length | Reserved | Prefix... 390 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 391 ...Prefix | 392 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 394 Type: 396 TBA Mobile Network Extension (skippable type range to be 397 assigned by IANA). 399 Length: 401 Decimal 8. 403 Sub-Type: 405 TBA (Explicit Mode Acknowledgement) 407 TBA (Implicit Mode Acknowledgement) 409 Code: 411 Value indicating success or failure: 413 TBA Success 415 TBA Invalid prefix (MOBNET_INVALID_PREFIX_LEN) 417 TBA Mobile Router is not authorized for prefix 418 (MOBNET_UNAUTHORIZED) 420 TBA Forwarding setup failed (MOBNET_FWDING_SETUP_FAILED) 422 Prefix Length: 424 8-bit unsigned integer indicating the number of leftmost bits 425 covering the network part of the address contained in the 426 Prefix field. 428 Reserved: 430 Sent as zero; ignored on reception. 432 Prefix: 434 32-bit unsigned integer in network byte-order containing an 435 IPv4 address whose leftmost Prefix Length bits make up the 436 Mobile Network Prefix. 438 5. Mobile Router Operation 440 A Mobile Router's operation is generally derived from the behavior of 441 a Mobile Node, as set in RFC 3344 [RFC3344]. In addition to 442 maintaining mobility bindings for its Home Address, the Mobile 443 Router, together with the Home Agent, maintains forwarding 444 information for the Mobile Network Prefix(es) assigned to the Mobile 445 Router. 447 A Mobile Router SHOULD set the 'T' bit to 1 in all Registration 448 Request messages it sends to indicate the need for reverse tunnels 449 for all traffic. Without reverse tunnels, all the traffic from the 450 mobile network will be subject to ingress filtering in the visited 451 networks. Upon reception of a successful Registration Reply, the 452 Mobile Router processes the registration in accordance to RFC 3344 453 [RFC3344]. In addition, the following steps are taken: 455 o Check for Mobile Network Acknowledgement extension(s) in 456 Registration Reply 458 o Create tunnel to the Home Agent if registered in reverse tunneling 459 mode 461 o Set up default route via this tunnel or egress interface when 462 registered with or without reverse tunneling, respectively 464 In accordance with this specification, a Mobile Router may operate in 465 one of the following two modes: explicit and implicit. In explicit 466 mode, the Mobile Router includes Mobile Network Prefix information in 467 all Registration Requests (as Mobile Network Request extensions), 468 while in implicit mode it does not include this information in any 469 Registration Request. In this latter case, the Home Agent obtains 470 the Mobile Network Prefixes by other means than Mobile IP. One 471 example of obtaining the Mobile Network Prefix is through static 472 configuration on the Home Agent. 474 A Mobile Router can obtain a Collocated or Foreign Agent Care-of 475 Address while operating in explicit or implicit modes. 477 For de-registration, the Mobile Router sends a registration request 478 with lifetime set to zero without any Mobile Network Request 479 extensions. 481 5.1. Error Processing 483 In a Mobile IP Registration Reply message there may be two Code 484 fields: one proper to the Registration Reply header (the 'proper' 485 Code) and one within the Mobile Network Acknowledgement Extension 486 (simply the 'Code'). A Mobile Router interprets the values of the 487 Code field in the Mobile Network Acknowledgement Extension of the 488 Registration Reply in order to identify any error related to managing 489 the Mobile Network Prefixes by the Home Agent. It also interprets 490 the values of the Code field in the Registration Reply header (the 491 proper Code). 493 If the value of the Code field in the Registration Reply (the proper) 494 is set to HA_MOBNET_DISALLOWED, then the Mobile Router MUST stop 495 sending Registration Requests with any Mobile Network Prefix 496 extensions to that Home Agent. 498 If the value of the Code field in the Registration Reply (the proper) 499 is set to HA_MOBNET_ERROR then the Mobile Router MUST stop sending 500 Registration Requests that contain any of the Mobile Network Prefixes 501 that are defined by the values of the fields Prefix and Prefix Length 502 in the Mobile Network Acknowledgement extension. Note that the 503 registration is denied in this case and no forwarding for any Mobile 504 Network Prefixes would be set up by the Home Agent for the Mobile 505 Router. 507 It is possible that the Mobile Router receives a Registration Reply 508 with no mobile network extensions if the registration was processed 509 by a Mobile IPv4 home agent that does not support this specification 510 at all. In that case, the absence of mobile network extensions must 511 be interpreted by the Mobile Router as the case where the Home Agent 512 does not support mobile networks. 514 All the error code values are TBA (To Be Assigned) subject to IANA 515 allocation. 517 5.2. Mobile Router Management 519 Operating a Mobile Router in a Mobile IPv4 environment has certain 520 requirements on the management of the necessary initial configuration 521 and supervision of the ongoing status information. Mobile Router 522 maintenance indicators may need to be exposed in a manner consistent 523 with other Mobile IPv4 indicators. 525 The objects for the Management Information Base (MIB) for Mobile IPv4 526 are defined in RFC 2006 [RFC2006]. The structure of the basic model 527 of Mobile IP protocol describes three entities: Mobile Node, Home 528 Agent and Foreign Agent. In addition to these entities this document 529 proposes a functional entity to be the Mobile Router. 531 The necessary initial configuration at a NEMOv4-enabled Home Agent 532 includes, but is not limited to, the contents of the Prefix Table. 533 The Mobile Router MAY need to store the Mobile Network Prefixes as 534 the initial configuration. 536 The definition of MIB objects related to Mobile Router and of a 537 NEMOv4-enabled Home Agent is outside the scope of this document. 539 6. Home Agent Operation 541 6.1. Summary 543 A Home Agent MUST support all the operations specified in RFC 3344 544 [RFC3344] for Mobile Node support. The Home Agent MUST support both 545 implicit and explicit modes of operation for a Mobile Router. 547 The Home Agent processes the registration in accordance to RFC 3344 548 [RFC3344], which includes route set up to the Mobile Router's Home 549 Address via the tunnel to the Care-of Address. In addition, for a 550 Mobile Router registering in explicit mode, the following steps are 551 taken: 553 1. Check that the Mobile Network Prefix information is valid 555 2. Ensure the Mobile Network Prefix(es) is or are authorized to be 556 on the Mobile Router 558 3. Create tunnel to the Mobile Router if it does not already exist 560 4. Set up route for the Mobile Network Prefix via this tunnel 562 5. Propagate Mobile Network Prefix routes via routing protocol if 563 necessary 565 6. Send the Registration Reply with the Mobile Network 566 Acknowledgement extension(s) 568 If there are any subnet routes via the tunnel to the Mobile Router 569 that are not specified in the Mobile Network extensions, these routes 570 are removed. 572 In the case where the Mobile Node is not permitted to act as a Mobile 573 Router, the Home Agent sends a Registration Reply message whose Code 574 field is HA_MOBNET_DISALLOWED (the proper Code field of the 575 Registration Reply). 577 For a Mobile Router registering in implicit mode, the Home Agent 578 performs steps 3-6 above, once the registration request is processed 579 successfully. 581 For deregistration, the Home Agent removes the tunnel to the Mobile 582 Router and all routes using this tunnel. The Mobile Network 583 extensions are ignored. 585 6.2. Data Structures 587 6.2.1. Registration Table 589 The Registration Table in the Home Agent, in accordance with RFC 3344 590 [RFC3344], contains binding information for every Mobile Node 591 registered with it. RFC 3344 [RFC3344] defines the format of a 592 Registration Table. In addition to all the parameters specified by 593 RFC 3344 [RFC3344], the Home Agent MUST store the Mobile Network 594 Prefixes associated with the Mobile Router in the corresponding 595 registration entry, when the corresponding registration was performed 596 in explicit mode. When the Home Agent is advertising reachability to 597 Mobile Network Prefixes served by a Mobile Router, the information 598 stored in the Registration Table can be used. 600 6.2.2. Prefix Table 602 The Home Agent must be able to authorize a Mobile Router for use of 603 Mobile Network Prefixes when the Mobile Router is operating in 604 explicit mode. Also, when the Mobile Router operates in implicit 605 mode, the Home Agent must be able to locate the Mobile Network 606 Prefixes associated with that Mobile Router. The Home Agent may 607 store the Home Address of the Mobile Router along with the mobile 608 network prefixes associated with that Mobile Router. If the Mobile 609 Router does not have a Home Address assigned, this table may store 610 the NAI RFC 2794 [RFC2794] of the Mobile Router that will be used in 611 dynamic Home Address assignment. 613 6.3. Mobile Network Prefix Registration 615 The Home Agent must process registration requests coming from Mobile 616 Routers in accordance with this section. The document RFC 3344 618 [RFC3344] specifies that the Home Address of a mobile node 619 registering with a Home Agent must belong to a prefix advertised on 620 the home network. In accordance with this specification, however, 621 the Home Address must be configured from a prefix that is served by 622 the Home Agent, not necessarily the one on the home network. 624 If the registration request is valid, the Home Agent checks to see if 625 there are any Mobile Network Prefix extensions included in the 626 Registration Request. 628 If so, the Mobile Network Prefix information is obtained from the 629 included extensions, and the Home Address from the Home Address field 630 of the Registration Request. For every Mobile Network Prefix 631 extension included in the registration request, the Home Agent MUST 632 perform a check against the Prefix Table. If the Prefix Table does 633 not contain at least one entry pairing that Home Address to that 634 Mobile Network Prefix then the check fails, otherwise it succeeds. 636 Following this check against the Prefix Table, the Home Agent MUST 637 construct a Registration Reply containing Mobile Network 638 Acknowledgement extensions. For a Mobile Network Prefix for which 639 the check was unsuccessful the Code field in the corresponding Mobile 640 Network Acknowledgement extension should be set to 641 MOBNET_UNAUTHORIZED. 643 For a Mobile Network Prefix for which the check was successful the 644 Code field in the respective Mobile Network Acknowledgement 645 extensions should be set to 0. 647 The Home Agent MUST attempt to set up forwarding for each Mobile 648 Network Prefix extension for which the Prefix Table check was 649 successful. If the forwarding setup fails for a particular Mobile 650 Network Prefix (for reasons when, for example, there is not enough 651 memory available, or not enough devices available, or other reason) 652 the Code field in the respective Mobile Network Acknowledgement 653 extension should be set to MOBNET_FWDING_SETUP_FAILED. 655 If forwarding and setup was successful for at least one Mobile 656 Network Prefix then the Code field (proper) of the Registration Reply 657 message should be set to 0. Otherwise, when forwarding and setup was 658 unsuccessful for each and every Mobile Network Prefixes, that Code 659 (proper) should be HA_MOBNET_ERROR. 661 If the registration request is sent in implicit mode, i.e., without 662 any Mobile Network Request extension, the Home Agent may use pre- 663 configured mobile network prefix information for the Mobile Router to 664 set up forwarding. 666 If the Home Agent is updating an existing binding entry for the 667 Mobile Router, it MUST check all the prefixes in the registration 668 table against the prefixes included in the registration request. If 669 one or more mobile network prefix is missing from the included 670 information in the registration request, it MUST delete those 671 prefixes from the registration table. Also, the Home Agent MUST 672 disable forwarding for those prefixes. 674 If all checks are successful, the Home Agent either creates a new 675 entry for the Mobile Router or updates an existing binding entry for 676 it and returns a successful registration reply back to the Mobile 677 Router or the Foreign Agent (if the registration request was received 678 from a Foreign Agent). 680 In accordance with RFC 3344 [RFC3344], the Home Agent does proxy ARP 681 for the Mobile Router Home Address, when the Mobile Router Home 682 Address is derived from the home network. 684 If the 'T' bit is set, the Home Agent creates a bi-directional tunnel 685 for the corresponding mobile network prefixes or updates the existing 686 bi-directional tunnel. This tunnel is maintained independent of the 687 reverse tunnel for the Mobile Router home address itself. 689 6.4. Advertising Mobile Network Reachability 691 If the mobile network prefixes served by the Home Agent are 692 aggregated with the home network prefix and if the Home Agent is the 693 default router on the home network, the Home Agent does not have to 694 advertise the Mobile Network Prefixes. The routes for the Mobile 695 Network Prefix are automatically aggregated into the home network 696 prefix (it is assumed that the Mobile Network Prefixes are 697 automatically aggregated into the home network prefix). If the 698 Mobile Router updates the mobile network prefix routes via a dynamic 699 routing protocol, the Home Agent SHOULD propagate the routes on the 700 appropriate networks. 702 6.5. Establishment of Bi-directional Tunnel 704 The Home Agent creates and maintains a bi-directional tunnel for the 705 mobile network prefixes of a Mobile Router registered with it. A 706 home agent supporting IPv4 Mobile Router operation MUST be able to 707 forward packets destined to the mobile network prefixes served by the 708 Mobile Router to its Care-of Address. Also, the Home Agent MUST be 709 able to accept packets tunneled by the Mobile Router with the source 710 address of the outer header set to the Care-of Address of the Mobile 711 Router and that of the inner header set to the Mobile Router's Home 712 Address or an address from one of the registered mobile network 713 prefixes. 715 6.6. Sending Registration Replies 717 The Home Agent MUST set the status code in the registration reply to 718 0 to indicate successful processing of the registration request and 719 successful set up of forwarding for at least one mobile network 720 prefixes served by the Mobile Router. The registration reply MUST 721 contain at least one Mobile Network Acknowledgement extension. 723 If the Home Agent is unable to set up forwarding for one or more 724 mobile network prefixes served by the Mobile Router, it MUST set the 725 Mobile Network Acknowledgement Extension status Code in the 726 registration reply to MOBNET_FWDING_SETUP_FAILED. When the prefix 727 length is zero or greater than decimal 32, the status Code MUST be 728 set to MOBNET_INVALID_PREFIX_LEN. 730 If the Mobile Router is not authorized to forward packets to a mobile 731 network prefixes included in the request, the Home Agent MUST set the 732 Code to MOBNET_UNAUTHORIZED. 734 6.7. Mobile Network Prefix De-registration 736 If the received registration request is for de-registration of the 737 Care-of Address, the Home Agent, upon successful processing of it, 738 MUST delete the entry(ies) from its registration table. The home 739 agent tears down the bi-directional tunnel and stops forwarding any 740 packets to/from the Mobile Router. The Home Agent MUST ignore any 741 included Mobile Network Request extension in a de-registration 742 request. 744 7. Data Forwarding Operation 746 For traffic to the nodes in the Mobile Network, the Home Agent MUST 747 perform double tunneling of the packet, if the Mobile Router had 748 registered with a Foreign Agent Care-of Address. In this case, the 749 Home Agent MUST encapsulate the packet with tunnel header (source IP 750 address set to Home Agent and destination IP address set to Mobile 751 Router's Home Address) and then encapsulate one more time with tunnel 752 header (source IP address set to Home Agent and destination IP 753 address set to CoA). 755 For optimization, the Home Agent SHOULD only encapsulate the packet 756 with the tunnel header (source IP address set to Home Agent and 757 destination IP address set to CoA) for Collocated CoA mode. 759 When a Home Agent receives a packet from the mobile network prefix in 760 the bi-directional tunnel, it MUST de-encapsulate the packet and 761 route it as a normal IP packet. It MUST verify that the incoming 762 packet has the source IP address set to the Care-of Address of the 763 Mobile Router. The packet MUST be dropped if the source address is 764 not set to the Care-of Address of the Mobile Router. 766 For traffic from the nodes in the Mobile Network, the Mobile Router 767 encapsulates the packet with a tunnel header (source IP address set 768 to Mobile Router's Home Address and destination IP address set to 769 Home Agent) if reverse tunnel is enabled. Otherwise, the packet is 770 routed directly to the Foreign Agent or access router. 772 In Collocated CoA mode, the Mobile Router MAY encapsulate one more 773 times with a tunnel header (source IP address set to the CoA and 774 destination IP address set to Home Agent). 776 8. Nested Mobile Networks 778 Nested Network Mobility is a scenario where a Mobile Router allows 779 another Mobile Router to attach to its Mobile Network. There could 780 be arbitrary levels of nested mobility. The operation of each Mobile 781 Router remains the same whether the Mobile Router attaches to another 782 Mobile Router or to a fixed Access Router on the Internet. The 783 solution described here does not place any restriction on the number 784 of levels for nested mobility. Two issues should be noted though. 785 First, whenever physical loops occur in a nested aggregation of 786 mobile networks this protocol does neither detect nor solve them - 787 datagram forwarding may be blocked. Second, Mobile Routers in a deep 788 nested aggregation of mobile networks might introduce significant 789 overhead on the data packets as each level of nesting introduces 790 another tunnel header encapsulation. Applications that do not 791 support MTU discovery are adversely affected by the additional header 792 encapsulations, because the usable MTU is reduced with each level of 793 nesting. 795 9. Routing Protocol between Mobile Router and Home Agent 797 There are several benefits of running a dynamic routing protocol 798 between the Mobile Router and the Home Agent. If the mobile network 799 is relatively large, including several wireless subnets, then the 800 topology changes within the moving network can be exposed from the 801 Mobile Router to the Home Agent by using a dynamic routing protocol. 802 The purpose of the NEMOv4 protocol extensions to Mobile IPv4, as 803 defined in previous sections, is not to inform the Home Agent about 804 these topology changes, but to manage the mobility of the Mobile 805 Router. 807 Similarly, topology changes in the home network can be exposed to the 808 Mobile Router by using a dynamic routing protocol. This may be 809 necessary when new fixed networks are added in the home network. 810 Here too, the purpose of NEMOv4 extensions is not to inform the 811 Mobile Router about topology changes at home. 813 Examples of dynamic routing protocol include but are not limited to 814 OSPF Version 2 RFC 2328 [RFC2328], BGP RFC 4271 [RFC4271] and RIP 815 RFC 2453 [RFC2453]. 817 The recommendations are related to how the routing protocol and the 818 Mobile IPv4 implementation work in tandem on the Mobile Router and on 819 the Home Agent (1) without creating incoherent states in the 820 forwarding information bases at home and on the Mobile Router, (2) 821 without introducing topologically incorrect addressing information in 822 the visited domain and (3) efficiently avoid duplication of sent data 823 or over-provisioning of security. 825 The information exchanged between the Mobile Router and the Home 826 Agent is sent over the bi-directional tunnel established by the 827 Mobile IPv4 exchange Registration Request - Registration Reply (see 828 Section 6.5). If a network address and prefix about a subnet in the 829 moving network is sent by the Mobile Router within a routing protocol 830 message then they SHOULD NOT be sent in the Mobile IPv4 Registration 831 Request too, in order to avoid incoherencies in the forwarding 832 information bases. The Mobile Router SHOULD use NEMOv4 implicit mode 833 in this case (see Section 3). 835 The Mobile Router SHOULD NOT send routing protocol information 836 updates in the foreign network. The subnet addresses and prefixes 837 valid in the moving network are topologically incorrect in the 838 visited network. 840 If the Mobile Router and the Home Agent use a dynamic routing 841 protocol over the tunnel interface, and if that protocol offers 842 security mechanisms to protect that protocol's messages, then the 843 security recommendations in Section 10.1 apply. 845 10. Security Considerations 847 The Mobile Network extension is protected by the same rules for 848 Mobile IP extensions in registration messages. See the Security 849 Considerations section in RFC 3344 [RFC3344]. 851 The Home Agent MUST be able to verify that the Mobile Router is 852 authorized to provide mobility service for the Mobile Networks in the 853 registration request, before anchoring these Mobile Network Prefixes 854 on behalf of the Mobile Router. Forwarding for prefixes MUST NOT be 855 set up without successful authorization of the Mobile Router for 856 those prefixes. A registration failure MUST be notified to the 857 mobile router when it cannot be successfully authorized for prefixes 858 requested by it. 860 All registration requests and replies MUST be authenticated by the 861 MN-HA Authentication Extension as specified in RFC 3344 [RFC3344]. 862 When the registration request is sent in explicit mode, i.e., with 863 one or more Mobile Network Prefix extensions, all the Mobile Network 864 Prefix extensions MUST be included before the MN-HA Authentication 865 extension. Also, these extensions MUST be included in the 866 calculation of the MN-HA authenticator value. 868 The Mobile Router should perform ingress filtering on all the packets 869 received on the mobile network prior to reverse tunneling them to the 870 Home Agent. The Mobile Router MUST drop any packets that do not have 871 a source address belonging to the mobile network. 873 The Mobile Router MUST also ensure that the source address of packets 874 arriving on the mobile network is not the same as the Mobile Router's 875 IP address on any interface. These checks will protect against nodes 876 attempting to launch IP spoofing attacks through the bi-directional 877 tunnel. 879 The Home Agent, upon receiving packets through the bi-directional 880 tunnel, MUST verify that the source addresses of the outer IP header 881 of the packets are set to the Mobile Router's care-of-address. Also, 882 it MUST ensure that the source address of the inner IP header is a 883 topologically correct address on the mobile network. This will 884 prevent nodes from using the Home Agent to launch attacks inside the 885 protected network. 887 10.1. Security when Dynamic Routing Protocol is Used 889 If a dynamic routing protocol is used between the Mobile Router and 890 the Home Agent to propagate the mobile network information into the 891 home network, the routing updates SHOULD be protected with IPsec ESP 892 confidentiality between the Mobile Router and Home Agent, to prevent 893 information about home network topology from being visible to 894 eavesdroppers. 896 11. IANA Considerations 898 IANA to assign rules for the existing registry "Mobile IPv4 numbers - 899 per RFC 3344". The numbering space for Extensions that may appear in 900 Mobile IP control messages (those sent to and from UDP port number 901 434) should be modified. 903 The new Values and Names for the Type for Extensions appearing in 904 Mobile IP control messages are the following: 906 +-------+---------------------------------------------------+ 907 | Value | Name | 908 +-------+---------------------------------------------------+ 909 | TBA | Mobile Network Extension (To Be Assigned by IANA) | 910 +-------+---------------------------------------------------+ 912 Table 1: New Values and Names for Extensions in Mobile IP Control 913 Messages 915 A new number space should be created for the Values and Names for the 916 Sub-Type for Mobile Network Extensions. This number space is 917 initially defined to hold the following entries, allocated by this 918 document: 920 +-------+-----------------------------------------+ 921 | Value | Name | 922 +-------+-----------------------------------------+ 923 | TBA | Mobile Network Request Extension | 924 | TBA | Explicit Mode Acknowledgement Extension | 925 | TBA | Implicit Mode Acknowledgement Extension | 926 +-------+-----------------------------------------+ 928 Table 2: New Values and Names for the Sub-Type for Mobile Network 929 Extensions 931 The policy of future assignments to this number space should be 932 following Standards Action or IESG Approval (see [RFC2434]). 934 The new Code Values for Mobile IP Registration Reply messages are the 935 following (for a registration denied by the Home Agent): 937 +-------+-----------------------------------------------------------+ 938 | Value | Name | 939 +-------+-----------------------------------------------------------+ 940 | TBA | Mobile Network Prefix operation error (HA_MOBNET_ERROR) | 941 | TBA | Mobile Router operation is not permitted | 942 | | (HA_MOBNET_DISALLOWED) | 943 +-------+-----------------------------------------------------------+ 945 Table 3: New Code Values for Mobile IP Registration Reply 947 A new number space should be created for the Code Values for the 948 Mobile Network Acknowledgement Extension. This number space is 949 initially defined to hold the following entries, allocated by this 950 document (result of registration, as sent by the Home Agent): 952 +-----+-------------------------------------------------------------+ 953 | TBA | Success | 954 | TBA | Invalid prefix length (MOBNET_INVALID_PREFIX_LEN) | 955 | TBA | Mobile Router is not authorized for prefix | 956 | | (MOBNET_UNAUTHORIZED) | 957 | TBA | Forwarding setup failed (MOBNET_FWDING_SETUP_FAILED) | 958 +-----+-------------------------------------------------------------+ 960 Table 4: New Code Values for Mobile Network Acknowledgement Extension 962 The policy of future assignments to this number space should be 963 following Standards Action or IESG Approval (see [RFC2434]). 965 The current non-modified numbering spaces could be consulted at the 966 URL http://www.iana.org/assignments/mobileip-numbers (contents last 967 updated 2007-12-20 and last browsed 2008-01-04). 969 12. Acknowledgements 971 The authors would like to thank Christophe Janneteau, George 972 Popovich, Ty Bekiares, Ganesh Srinivasan, Alpesh Patel, Ryuji 973 Wakikawa, George Tsirtsis, and Henrik Levkowetz for their helpful 974 discussions, reviews and comments. Vijay Devarapalli extensively 975 reviewed one of the later versions of the draft. Hans Sjostrand 976 (Hans Sj\"ostrand) identified the last clarifications with respect to 977 Foreign Agent mode treatment. Pete McCann contributed necessary 978 refinements of many statements. 980 Mobile IPv4 versions as early as 1996 (RFC 2002) described Mobile 981 Networks and Mobile Routers support. Charles Perkins. 983 Fred Templin indicated the potential confusion for the term "LFN". 985 Amanda Baber of IANA agreed on the principles of allocating numbers 986 for this specification and suggested improvements on the IANA 987 section. 989 Tim Polk of IESG identified a deeply entrenched error on managing the 990 Code fields. 992 Lars Eggert of IESG suggested the acommodation of the otherwise legal 993 non-contiguous netmask fields, instead of simply prefix lengths. 995 Dan Romascanu of IESG indicated the necessity of manageability of 996 Mobile Routers and NEMOv4-enabled Home Agents and their deployability 997 in MIP4 environments. 999 David Borman of TSV-DIR reviewed this document as part of the 1000 transport area directorate's ongoing effort to review key IETF 1001 documents. The implications of the growth of usable MTU adversely 1002 affecting applications deep in a mobile network were suggested. 1004 Gonzalo Camarillo provided a generalist review by an additional set 1005 of eyes for documents as they are being considered for publication 1006 (General Area Review Team). 1008 Jari Arkko of IESG reviewed, suggested necessary improvements to, and 1009 diligently shepherded this document through IESG. 1011 13. References 1013 13.1. Normative References 1015 [RFC1323] Jacobson, V., Braden, B., and D. Borman, "TCP Extensions 1016 for High Performance", RFC 1323, May 1992. 1018 [RFC2006] Cong, D., Hamlen, M., and C. Perkins, "The Definitions of 1019 Managed Objects for IP Mobility Support using SMIv2", 1020 RFC 2006, October 1996. 1022 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 1023 Requirement Levels", BCP 14, RFC 2119, March 1997. 1025 [RFC2328] Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998. 1027 [RFC2434] Narten, T. and H. Alvestrand, "Guidelines for Writing an 1028 IANA Considerations Section in RFCs", BCP 26, RFC 2434, 1029 October 1998. 1031 [RFC2453] Malkin, G., "RIP Version 2", STD 56, RFC 2453, 1032 November 1998. 1034 [RFC2794] Calhoun, P. and C. Perkins, "Mobile IP Network Access 1035 Identifier Extension for IPv4", RFC 2794, March 2000. 1037 [RFC3344] Perkins, C., "IP Mobility Support for IPv4", RFC 3344, 1038 August 2002. 1040 [RFC4271] Rekhter, Y., Li, T., and S. Hares, "A Border Gateway 1041 Protocol 4 (BGP-4)", RFC 4271, January 2006. 1043 13.2. Informative References 1045 [I-D.ietf-mip4-nemov4-fa] 1046 Tsirtsis, G., Park, V., Narayanan, V., and K. Leung, "FA 1047 extensions to NEMOv4 Base", draft-ietf-mip4-nemov4-fa-02 1048 (work in progress), November 2007. 1050 [RFC3963] Devarapalli, V., Wakikawa, R., Petrescu, A., and P. 1051 Thubert, "Network Mobility (NEMO) Basic Support Protocol", 1052 RFC 3963, January 2005. 1054 [RFC4885] Ernst, T. and H-Y. Lach, "Network Mobility Support 1055 Terminology", RFC 4885, July 2007. 1057 Appendix A. ChangeLog 1059 [RFC Editor: please remove this section prior to publication. (said 1060 IESG member Russ Housley on 6th of February 2008: "Please delete 1061 Appendix A before publication as an RFC.")] 1063 The changes are listed in reverse chronological order, most recent 1064 changes appearing at the top of the list. 1066 From draft-ietf-mip4-nemo-v4-base-10.txt to 1067 draft-ietf-mip4-nemo-v4-base-11.txt: 1069 o Based on David Ward comment removed the section discussing on non- 1070 contiguous netmasks, as well as the Optional Netmask fields (but 1071 still kept the prefixlen-based contiguous netmasks.) 1073 From draft-ietf-mip4-nemo-v4-base-09.txt to 1074 draft-ietf-mip4-nemo-v4-base-10.txt: 1076 o Changed "192.168.1.1" notation to "192.0.2.0" documentation style 1077 addresses, as suggested by idnits. 1079 From draft-ietf-mip4-nemo-v4-base-08.txt to 1080 draft-ietf-mip4-nemo-v4-base-09.txt, following IANA and IESG 1081 comments: 1083 o Introduced an Optional Netmask field in both registrations and 1084 replies. This is used when address/prefixlength is not a 1085 sufficient expression of network mask, for example when the subnet 1086 mask needs to be expressed as a non-contiguous set of 1bits (e.g. 1087 255.255.0.255). Also described the reasoning of this in a section 1088 of its own. 1090 o Extended the Introduction section with two subsections: example of 1091 mobile network and overall protocol operation. Illustrated two 1092 figures. 1094 o Added Local Fixed Node term definition and some citations to 1095 reference rfc4885 "Network Mobility Support Terminology". 1097 o Clarified text about the Code field. There are two Code fields: 1098 one in Registration Reply header (the Code proper) and one in the 1099 Mobile Network Extension header. Also clarified conditions of 1100 proper Code being 0 successful and and relationships of proper 1101 Code 0 to Code in the Mobile Network Extension. 1103 o Added a sub-section 'Mobile Router Management' about the initial 1104 configuration, ongoing supervision and management indicators of a 1105 Mobile Router and Home Agent. 1107 o Substituted 'MOBNET_UNAUTHORIZED' for 'MOBNET_UNAUTHORIZED_MR'. 1109 o Substituted 'IANA to assign rules' for 'IANA to modify rules'. 1111 o Stressed that "applications that do not support MTU discovery are 1112 adversely affected by the additional header encapsulations, 1113 because the usable MTU is reduced with each level of nesting." 1115 o Removed citations and reference to rfc3344bis 1116 (draft-ietf-mip4-rfc3344bis-05). 1118 o Removed citations and reference to rfc2434bis 1119 (draft-narten-iana-considerations-rfc2434bis-08). 1121 o Extended the Acknowledgements section. 1123 From draft-ietf-mip4-nemo-v4-base-07.txt to 1124 draft-ietf-mip4-nemo-v4-base-08.txt, following AD Review (Jari 1125 Arkko): 1127 o HA propagates Mobile Network Prefix only if necessary (previously 1128 it was always doing it). 1130 o emphasized that within nested mobile networks looping may occur 1131 and this document doesn't do anything to address this. 1133 o dropped a phrase which said that Mobile-Home auth extension 1134 shouldn't be used when ESP protects the routing protocol message, 1135 because that extension is only applied to Registration messages 1136 (not tunneled data, which usually contains routing protocol 1137 exchange). 1139 o recommending "Standards Action or IESG Review" instead of "Expert 1140 Review" for this numbering space, and added reference to a draft 1141 for 2434bis. 1143 o editorial: re-phrased about how Mobile IPv4 claimed mobile 1144 networks support. 1146 o editorial: added a necessary paragraph in the Acknowledgements 1147 section. 1149 From draft-ietf-mip4-nemo-v4-base-06.txt to 1150 draft-ietf-mip4-nemo-v4-base-07.txt 1152 o encoded the draft into xml. Compiled with xml2rfc version 1153 1.33pre4. 1155 o checked against 'idnits' script version 2.05.03. 1157 o substituted 'Care-of Address' for 'CoA'. 1159 From draft-ietf-mip4-nemo-v4-base-05.txt to 1160 draft-ietf-mip4-nemo-v4-base-06.txt 1162 o substituted "TBA" for "1" in Sub-type of Mobile Network Request 1163 Extension. 1165 o substituted "TBA" for "0" in Code of Mobile Network 1166 Acknowledgement Extension and in the IANA Section. 1168 o modified the IANA section to request definition two new spaces 1169 (instead of just defining new values) for Sub-Type of Mobile 1170 Network Extensions and for Code Values for Mobile Network 1171 Acknowledgement Extension, and to suggest "Expert Review" as 1172 method of new assignments in these two spaces (and not necessarily 1173 "IETF Consensus"). 1175 From draft-ietf-mip4-nemo-v4-base-04.txt to 1176 draft-ietf-mip4-nemo-v4-base-05.txt 1178 o updated the Acknowledgements section. 1180 o capitalized all occurences of "Home Address", "Mobile Router" and 1181 "Care-of Address". 1183 o refined many statements. 1185 o checked against 'idnits' script version 2.04.16. 1187 From draft-ietf-mip4-nemo-v4-base-03.txt to 1188 draft-ietf-mip4-nemo-v4-base-04.txt 1190 o more changes in Introduction to say that with FA mode only the 1191 non-optimized double-encapsulation operation is supported and 1192 [I-D.ietf-mip4-nemov4-fa] proposes a optimization. 1194 From draft-ietf-mip4-nemo-v4-base-02.txt to 1195 draft-ietf-mip4-nemo-v4-base-03.txt 1197 o changed a sentence in the Introduction to say that FA mode _is_ 1198 supported but unoptimized, and that a reference 1199 [I-D.ietf-mip4-nemov4-fa] optimizes that mode. 1201 o added I-D.ietf-mip4-rfc3344bis reference to the rfc3344bis draft. 1203 From draft-ietf-mip4-nemo-v4-base-01.txt to 1204 draft-ietf-mip4-nemo-v4-base-02.txt 1206 o changed title from "IPv4 Network Mobility (NEMO) Protocol" to 1207 "Network Mobility (NEMO) Extensions for Mobile IPv4". 1209 From draft-ietf-mip4-nemo-v4-base-00.txt to 1210 draft-ietf-mip4-nemo-v4-base-01.txt 1212 o added a section on Routing Protocol between Mobile Router and Home 1213 Agent. 1215 o added a security subsection about running simultaneously a secure 1216 routing protocol with secure Mobile IPv4. 1218 o added a date tag on the IANA URL for Mobile IP numbering spaces. 1220 o substituted 'Mobile Router' for 'MR' everywhere. 1222 o updated reference to NEMOv4 FA draft. 1224 From draft-ietf-nemo-v4-base-01.txt to 1225 draft-ietf-mip4-nemo-v4-base-00.txt: 1227 o changed draft name, headers and footers. 1229 o changed title. 1231 o a more coherent use of terms 'subnet', 'prefix' and 'mobile 1232 network'. 1234 o clarified only co-located CoA mode is supported (not FA CoA) for 1235 Mobile Routers in this specification. And added reference to the 1236 FA NEMO optimizations draft. 1238 o changed 'devices' to 'hosts'. 1240 o changed 'moving networks' to 'mobile networks'. 1242 o clarified what 'reachability' in a certain context is: packets may 1243 be dropped if ingress filtering is turned on. 1245 o removed the MR-FA-CoA tunnel overhead optimization. There is 1246 still an issue with text at HA doing optimization. 1248 This document was first presented as an individual contribution to 1249 the NEMO Working Group, then adopted as a WG item to that group. The 1250 01 version in the NEMO WG has been Last Called on the INFORMATIONAL 1251 track. The evolution was: 1253 From version draft-ietf-nemo-v4-base-00 to 1254 draft-ietf-nemo-v4-base-01: 1256 o removed error code HA_MOBNET_UNSUPPORTED. 1258 o changed all values to be assigned by IANA, from specific numbers 1259 to "TBA" (To Be Assigned). 1261 o substituted "egress interface" for "roaming interface". 1263 o changed HA behaviour upon reception of MNPs. In 00 the HA replied 1264 positively only if all MNPs in RegReq were valid, in 01 a reply is 1265 constructed specifying which MNP was valid and which not. 1267 o clarified a 3-line paragraph saying that RegRep may contain both 1268 implicit and explicit acknowledgements. 1270 Authors' Addresses 1272 Kent Leung 1273 Cisco Systems 1274 170 W. Tasman Drive 1275 San Jose, CA 95134 1276 USA 1278 Phone: +1 408-526-5030 1279 Email: kleung@cisco.com 1280 Gopal Dommety 1281 Cisco Systems 1282 170 W. Tasman Drive 1283 San Jose, CA 95134 1284 USA 1286 Phone: +1 408-525-1404 1287 Email: gdommety@cisco.com 1289 Vidya Narayanan 1290 QUALCOMM, Inc. 1291 5775 Morehouse Dr 1292 San Diego, CA 1293 USA 1295 Phone: +1 858-845-2483 1296 Email: vidyan@qualcomm.com 1298 Alexandru Petrescu 1299 Motorola 1300 Parc les Algorithmes Saint Aubin 1301 Gif-sur-Yvette, Essonne 91140 1302 France 1304 Phone: +33 169354827 1305 Email: alexandru.petrescu@motorola.com 1307 Full Copyright Statement 1309 Copyright (C) The IETF Trust (2008). 1311 This document is subject to the rights, licenses and restrictions 1312 contained in BCP 78, and except as set forth therein, the authors 1313 retain all their rights. 1315 This document and the information contained herein are provided on an 1316 "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS 1317 OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND 1318 THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS 1319 OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF 1320 THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED 1321 WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. 1323 Intellectual Property 1325 The IETF takes no position regarding the validity or scope of any 1326 Intellectual Property Rights or other rights that might be claimed to 1327 pertain to the implementation or use of the technology described in 1328 this document or the extent to which any license under such rights 1329 might or might not be available; nor does it represent that it has 1330 made any independent effort to identify any such rights. 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