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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Internet Engineering Task Force E. Jankiewicz 3 Internet-Draft SRI International 4 Intended status: Informational J. Loughney 5 Expires: January 13, 2011 Nokia 6 T. Narten 7 IBM Corporation 8 July 12, 2010 10 IPv6 Node Requirements RFC 4294-bis 11 draft-ietf-6man-node-req-bis-05.txt 13 Abstract 15 This document defines requirements for IPv6 nodes. It is expected 16 that IPv6 will be deployed in a wide range of devices and situations. 17 Specifying the requirements for IPv6 nodes allows IPv6 to function 18 well and interoperate in a large number of situations and 19 deployments. 21 Status of this Memo 23 This Internet-Draft is submitted in full conformance with the 24 provisions of BCP 78 and BCP 79. 26 Internet-Drafts are working documents of the Internet Engineering 27 Task Force (IETF). Note that other groups may also distribute 28 working documents as Internet-Drafts. The list of current Internet- 29 Drafts is at http://datatracker.ietf.org/drafts/current/. 31 Internet-Drafts are draft documents valid for a maximum of six months 32 and may be updated, replaced, or obsoleted by other documents at any 33 time. It is inappropriate to use Internet-Drafts as reference 34 material or to cite them other than as "work in progress." 36 This Internet-Draft will expire on January 13, 2011. 38 Copyright Notice 40 Copyright (c) 2010 IETF Trust and the persons identified as the 41 document authors. All rights reserved. 43 This document is subject to BCP 78 and the IETF Trust's Legal 44 Provisions Relating to IETF Documents 45 (http://trustee.ietf.org/license-info) in effect on the date of 46 publication of this document. Please review these documents 47 carefully, as they describe your rights and restrictions with respect 48 to this document. Code Components extracted from this document must 49 include Simplified BSD License text as described in Section 4.e of 50 the Trust Legal Provisions and are provided without warranty as 51 described in the Simplified BSD License. 53 This document may contain material from IETF Documents or IETF 54 Contributions published or made publicly available before November 55 10, 2008. The person(s) controlling the copyright in some of this 56 material may not have granted the IETF Trust the right to allow 57 modifications of such material outside the IETF Standards Process. 58 Without obtaining an adequate license from the person(s) controlling 59 the copyright in such materials, this document may not be modified 60 outside the IETF Standards Process, and derivative works of it may 61 not be created outside the IETF Standards Process, except to format 62 it for publication as an RFC or to translate it into languages other 63 than English. 65 Table of Contents 67 1. Requirements Language . . . . . . . . . . . . . . . . . . . . 4 68 2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 69 2.1. Scope of This Document . . . . . . . . . . . . . . . . . . 4 70 2.2. Description of IPv6 Nodes . . . . . . . . . . . . . . . . 4 71 3. Abbreviations Used in This Document . . . . . . . . . . . . . 5 72 4. Sub-IP Layer . . . . . . . . . . . . . . . . . . . . . . . . . 5 73 5. IP Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 74 5.1. Internet Protocol Version 6 - RFC 2460 . . . . . . . . . . 6 75 5.2. Neighbor Discovery for IPv6 - RFC 4861 . . . . . . . . . . 7 76 5.3. SEcure Neighbor Discovery (SEND) - RFC 3971 . . . . . . . 8 77 5.4. IPv6 Router Advertisement Flags Option - RFC 5175 . . . . 8 78 5.5. Path MTU Discovery and Packet Size . . . . . . . . . . . . 8 79 5.5.1. Path MTU Discovery - RFC 1981 . . . . . . . . . . . . 8 80 5.6. IPv6 Jumbograms - RFC 2675 . . . . . . . . . . . . . . . . 9 81 5.7. ICMP for the Internet Protocol Version 6 (IPv6) - RFC 82 4443 . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 83 5.8. Addressing . . . . . . . . . . . . . . . . . . . . . . . . 9 84 5.8.1. IP Version 6 Addressing Architecture - RFC 4291 . . . 9 85 5.8.2. IPv6 Stateless Address Autoconfiguration - RFC 4862 . 9 86 5.8.3. Privacy Extensions for Address Configuration in 87 IPv6 - RFC 4941 . . . . . . . . . . . . . . . . . . . 9 88 5.8.4. Default Address Selection for IPv6 - RFC 3484 . . . . 10 89 5.8.5. Stateful Address Autoconfiguration . . . . . . . . . . 10 90 5.9. Multicast Listener Discovery (MLD) for IPv6 - RFC 2710 . . 10 91 6. DHCP vs. Router Advertisement Options for Host 92 Configuration . . . . . . . . . . . . . . . . . . . . . . . . 11 93 7. DNS and DHCP . . . . . . . . . . . . . . . . . . . . . . . . . 12 94 7.1. DNS . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 95 7.2. Dynamic Host Configuration Protocol for IPv6 (DHCPv6) 96 - RFC 3315 . . . . . . . . . . . . . . . . . . . . . . . . 12 97 7.2.1. Managed Address Configuration . . . . . . . . . . . . 12 98 7.2.2. Other Configuration Information . . . . . . . . . . . 12 99 7.2.3. Use of Router Advertisements in Managed 100 Environments . . . . . . . . . . . . . . . . . . . . . 13 101 7.3. IPv6 Router Advertisement Options for DNS 102 Configuration - RFC XXXX . . . . . . . . . . . . . . . . . 13 103 8. IPv4 Support and Transition . . . . . . . . . . . . . . . . . 13 104 8.1. Transition Mechanisms . . . . . . . . . . . . . . . . . . 13 105 8.1.1. Basic Transition Mechanisms for IPv6 Hosts and 106 Routers - RFC 4213 . . . . . . . . . . . . . . . . . . 13 107 9. Mobility . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 108 10. Security . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 109 10.1. Basic Architecture . . . . . . . . . . . . . . . . . . . . 14 110 10.2. Security Protocols . . . . . . . . . . . . . . . . . . . . 14 111 10.3. Transforms and Algorithms . . . . . . . . . . . . . . . . 14 112 10.4. Key Management Methods . . . . . . . . . . . . . . . . . . 15 113 11. Router-Specific Functionality . . . . . . . . . . . . . . . . 15 114 11.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 15 115 11.1.1. IPv6 Router Alert Option - RFC 2711 . . . . . . . . . 15 116 11.1.2. Neighbor Discovery for IPv6 - RFC 4861 . . . . . . . . 15 117 12. Network Management . . . . . . . . . . . . . . . . . . . . . . 15 118 12.1. Management Information Base Modules (MIBs) . . . . . . . . 16 119 12.1.1. IP Forwarding Table MIB . . . . . . . . . . . . . . . 16 120 12.1.2. Management Information Base for the Internet 121 Protocol (IP) . . . . . . . . . . . . . . . . . . . . 16 122 13. Open Issues . . . . . . . . . . . . . . . . . . . . . . . . . 16 123 14. Security Considerations . . . . . . . . . . . . . . . . . . . 16 124 15. Authors and Acknowledgments . . . . . . . . . . . . . . . . . 16 125 15.1. Authors and Acknowledgments (Current Document) . . . . . . 16 126 15.2. Authors and Acknowledgments From RFC 4279 . . . . . . . . 16 127 16. Appendix: Changes from -04 to -05 . . . . . . . . . . . . . . 17 128 17. Appendix: Changes from -03 to -04 . . . . . . . . . . . . . . 18 129 18. Appendix: Changes from RFC 4294 . . . . . . . . . . . . . . . 18 130 19. References . . . . . . . . . . . . . . . . . . . . . . . . . . 18 131 19.1. Normative References . . . . . . . . . . . . . . . . . . . 18 132 19.2. Informative References . . . . . . . . . . . . . . . . . . 21 133 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 22 135 1. Requirements Language 137 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 138 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 139 document are to be interpreted as described in RFC 2119 [RFC2119]. 141 2. Introduction 143 The goal of this document is to define the common functionality 144 required from both IPv6 hosts and routers. Many IPv6 nodes will 145 implement optional or additional features, but this document collects 146 and summarizes requirements from other published Standards Track 147 documents in one place. 149 This document tries to avoid discussion of protocol details, and 150 references RFCs for this purpose. This document is intended to be an 151 Applicability Statement and provide guidance as to which IPv6 152 specifications should be implemented in the general case. This 153 document does not update any individual protocol document RFCs. 155 Although the document points to different specifications, it should 156 be noted that in most cases, the granularity of requirements are 157 smaller than a single specification, as many specifications define 158 multiple, independent pieces, some of which may not be mandatory. 160 As it is not always possible for an implementer to know the exact 161 usage of IPv6 in a node, an overriding requirement for IPv6 nodes is 162 that they should adhere to Jon Postel's Robustness Principle: 164 Be conservative in what you do, be liberal in what you accept from 165 others [RFC0793]. 167 2.1. Scope of This Document 169 IPv6 covers many specifications. It is intended that IPv6 will be 170 deployed in many different situations and environments. Therefore, 171 it is important to develop the requirements for IPv6 nodes to ensure 172 interoperability. 174 This document assumes that all IPv6 nodes meet the minimum 175 requirements specified here. 177 2.2. Description of IPv6 Nodes 179 From the Internet Protocol, Version 6 (IPv6) Specification [RFC2460], 180 we have the following definitions: 182 Description of an IPv6 Node 184 - a device that implements IPv6. 186 Description of an IPv6 router 188 - a node that forwards IPv6 packets not explicitly addressed to 189 itself. 191 Description of an IPv6 Host 193 - any node that is not a router. 195 3. Abbreviations Used in This Document 197 ATM Asynchronous Transfer Mode 198 AH Authentication Header 199 DAD Duplicate Address Detection 200 ESP Encapsulating Security Payload 201 ICMP Internet Control Message Protocol 202 IKE Internet Key Exchange 203 MIB Management Information Base 204 MLD Multicast Listener Discovery 205 MTU Maximum Transfer Unit 206 NA Neighbor Advertisement 207 NBMA Non-Broadcast Multiple Access 208 ND Neighbor Discovery 209 NS Neighbor Solicitation 210 NUD Neighbor Unreachability Detection 211 PPP Point-to-Point Protocol 212 PVC Permanent Virtual Circuit 213 SVC Switched Virtual Circuit 215 4. Sub-IP Layer 217 An IPv6 node must include support for one or more IPv6 link-layer 218 specifications. Which link-layer specifications are included will 219 depend upon what link-layers are supported by the hardware available 220 on the system. It is possible for a conformant IPv6 node to support 221 IPv6 on some of its interfaces and not on others. 223 As IPv6 is run over new layer 2 technologies, it is expected that new 224 specifications will be issued. In the following, we list some of the 225 link-layers for which an IPv6 specification has been developed. It 226 is provided for information purposes only, and may not be complete. 228 - Transmission of IPv6 Packets over Ethernet Networks [RFC2464] 229 - IPv6 over ATM Networks [RFC2492] 230 - Transmission of IPv6 Packets over Frame Relay Networks 231 Specification [RFC2590] 232 - Transmission of IPv6 Packets over IEEE 1394 Networks [RFC3146] 233 - Transmission of IPv6, IPv4, and Address Resolution Protocol (ARP) 234 Packets over Fibre Channel [RFC4338] 235 - Transmission of IPv6 Packets over IEEE 802.15.4 Networks [RFC4944] 236 - Transmission of IPv6 via the IPv6 Convergence Sublayer over IEEE 237 802.16 Networks [RFC5121] 238 - IP version 6 over PPP [RFC5072] 240 In addition to traditional physical link-layers, it is also possible 241 to tunnel IPv6 over other protocols. Examples include: 243 - Teredo: Tunneling IPv6 over UDP through Network Address 244 Translations (NATs) [RFC4380] 245 - Transmission of IPv6 over IPv4 Domains without Explicit Tunnels 246 [RFC2529] 248 5. IP Layer 250 5.1. Internet Protocol Version 6 - RFC 2460 252 The Internet Protocol Version 6 is specified in [RFC2460]. This 253 specification MUST be supported. 255 Unrecognized options in Hop-by-Hop Options or Destination Options 256 extensions MUST be processed as described in RFC 2460. 258 The node MUST follow the packet transmission rules in RFC 2460. 260 Nodes MUST always be able to send, receive, and process fragment 261 headers. All conformant IPv6 implementations MUST be capable of 262 sending and receiving IPv6 packets; the forwarding functionality MAY 263 be supported. 265 RFC 2460 specifies extension headers and the processing for these 266 headers. 268 A full implementation of IPv6 includes implementation of the 269 following extension headers: Hop-by-Hop Options, Routing (Type 0), 270 Fragment, Destination Options, Authentication and Encapsulating 271 Security Payload [RFC2460]. 273 An IPv6 node MUST be able to process these headers. An exception is 274 Routing Header type 0 (RH0) which was deprecated by [RFC5095] due to 275 security concerns, and which MUST be treated as an unrecognized 276 routing type. 278 5.2. Neighbor Discovery for IPv6 - RFC 4861 280 Neighbor Discovery SHOULD be supported. [RFC4861] states: 282 Unless specified otherwise (in a document that covers operating IP 283 over a particular link type) this document applies to all link 284 types. However, because ND uses link-layer multicast for some of 285 its services, it is possible that on some link types (e.g., NBMA 286 links) alternative protocols or mechanisms to implement those 287 services will be specified (in the appropriate document covering 288 the operation of IP over a particular link type). The services 289 described in this document that are not directly dependent on 290 multicast, such as Redirects, Next-hop determination, Neighbor 291 Unreachability Detection, etc., are expected to be provided as 292 specified in this document. The details of how one uses ND on 293 NBMA links is an area for further study. 295 Some detailed analysis of Neighbor Discovery follows: 297 Router Discovery is how hosts locate routers that reside on an 298 attached link. Router Discovery MUST be supported for 299 implementations. 301 Prefix Discovery is how hosts discover the set of address prefixes 302 that define which destinations are on-link for an attached link. 303 Prefix discovery MUST be supported for implementations. Neighbor 304 Unreachability Detection (NUD) MUST be supported for all paths 305 between hosts and neighboring nodes. It is not required for paths 306 between routers. However, when a node receives a unicast Neighbor 307 Solicitation (NS) message (that may be a NUD's NS), the node MUST 308 respond to it (i.e., send a unicast Neighbor Advertisement). 310 Duplicate Address Detection MUST be supported on all links supporting 311 link-layer multicast (RFC 4862, Section 5.4, specifies DAD MUST take 312 place on all unicast addresses). 314 A host implementation MUST support sending Router Solicitations. 316 Receiving and processing Router Advertisements MUST be supported for 317 host implementations. The ability to understand specific Router 318 Advertisement options is dependent on supporting the specification 319 where the RA is specified. 321 Sending and Receiving Neighbor Solicitation (NS) and Neighbor 322 Advertisement (NA) MUST be supported. NS and NA messages are 323 required for Duplicate Address Detection (DAD). 325 Redirect functionality SHOULD be supported. If the node is a router, 326 Redirect functionality MUST be supported. 328 5.3. SEcure Neighbor Discovery (SEND) - RFC 3971 330 SEND [RFC3971] and Cryptographically Generated Address (CGA) 331 [RFC3972] provide a way to secure the message exchanges of Neighbor 332 Discovery. SEND is a new technology, in that it has no IPv4 333 counterpart but it has significant potential to address certain 334 classes of spoofing attacks. While there have been some 335 implementations of SEND, there has been only limited deployment 336 experience to date in using the technology. In addition, the IETF 337 working group Cga & Send maIntenance (csi) is currently working on 338 additional extensions intended to make SEND more attractive for 339 deployment. 341 At this time, SEND is considered optional and IPv6 nodes MAY provide 342 SEND functionality. 344 5.4. IPv6 Router Advertisement Flags Option - RFC 5175 346 Router Advertisements include an 8-bit field of single-bit Router 347 Advertisement flags. The Router Advertisement Flags Option extends 348 the number of available flag bits by 48 bits. At the time of this 349 writing, 6 of the original 8 bit flags have been assigned, while 2 350 remain available for future assignment. No flags have been defined 351 that make use of the new option, and thus strictly speaking, there is 352 no requirement to implement the option today. However, 353 implementations that are able to pass unrecognized options to a 354 higher level entity that may be able to understand them (e.g., a 355 user-level process using a "raw socket" facility), MAY take steps to 356 handle the option in anticipation of a future usage. 358 5.5. Path MTU Discovery and Packet Size 360 5.5.1. Path MTU Discovery - RFC 1981 362 From [RFC2460]: 364 It is strongly recommended that IPv6 nodes implement Path MTU 365 Discovery [RFC1981], in order to discover and take advantage of 366 path MTUs greater than 1280 octets. However, a minimal IPv6 367 implementation (e.g., in a boot ROM) may simply restrict itself to 368 sending packets no larger than 1280 octets, and omit 369 implementation of Path MTU Discovery. 371 The rules in RFC 2460 MUST be followed for packet fragmentation and 372 reassembly. 374 5.6. IPv6 Jumbograms - RFC 2675 376 IPv6 Jumbograms [RFC2675] MAY be supported. 378 5.7. ICMP for the Internet Protocol Version 6 (IPv6) - RFC 4443 380 ICMPv6 [RFC4443] MUST be supported. 382 5.8. Addressing 384 5.8.1. IP Version 6 Addressing Architecture - RFC 4291 386 The IPv6 Addressing Architecture [RFC4291] MUST be supported. 388 5.8.2. IPv6 Stateless Address Autoconfiguration - RFC 4862 390 IPv6 Stateless Address Autoconfiguration is defined in [RFC4862]. 391 This specification MUST be supported for nodes that are hosts. 392 Static address can be supported as well. 394 Nodes that are routers MUST be able to generate link local addresses 395 as described in RFC 4862 [RFC4862]. 397 From 4862: 399 The autoconfiguration process specified in this document applies 400 only to hosts and not routers. Since host autoconfiguration uses 401 information advertised by routers, routers will need to be 402 configured by some other means. However, it is expected that 403 routers will generate link-local addresses using the mechanism 404 described in this document. In addition, routers are expected to 405 successfully pass the Duplicate Address Detection procedure 406 described in this document on all addresses prior to assigning 407 them to an interface. 409 Duplicate Address Detection (DAD) MUST be supported. 411 5.8.3. Privacy Extensions for Address Configuration in IPv6 - RFC 4941 413 Privacy Extensions for Stateless Address Autoconfiguration [RFC4941] 414 addresses a specific problem involving a client device whose user is 415 concerned about its activity or location being tracked. The problem 416 arises both for a static client and for one that regularly changes 417 its point of attachment to the Internet. When using Stateless 418 Address Autoconfiguration [RFC4862], the Interface Identifier portion 419 of formed addresses stays constant and is globally unique. Thus, 420 although a node's global IPv6 address will change if it changes its 421 point of attachment, the Interface Identifier portion of those 422 addresses remain the same, making it possible for servers to track 423 the location of an individual device as it moves around, or its 424 pattern of activity if it remains in one place. This may raise 425 privacy concerns as described in [RFC4862]. 427 In such situations, RFC4941 SHOULD be implemented. In other cases, 428 such as with dedicated servers in a data center, RFC4941 provides 429 limited or no benefit. 431 5.8.4. Default Address Selection for IPv6 - RFC 3484 433 The rules specified in the Default Address Selection for IPv6 434 [RFC3484] document MUST be implemented. It is expected that IPv6 435 nodes will need to deal with multiple addresses. 437 5.8.5. Stateful Address Autoconfiguration 439 Stateful Address Autoconfiguration MAY be supported. DHCPv6 440 [RFC3315] is the standard stateful address configuration protocol; 441 see Section 6.2 for DHCPv6 support. 443 Nodes which do not support Stateful Address Autoconfiguration may be 444 unable to obtain any IPv6 addresses, aside from link-local addresses, 445 when it receives a router advertisement with the 'M' flag (Managed 446 address configuration) set and that contains no prefixes advertised 447 for Stateless Address Autoconfiguration (see Section 4.5.2). 448 Additionally, such nodes will be unable to obtain other configuration 449 information, such as the addresses of DNS servers when it is 450 connected to a link over which the node receives a router 451 advertisement in which the 'O' flag (Other stateful configuration) is 452 set. 454 5.9. Multicast Listener Discovery (MLD) for IPv6 - RFC 2710 456 Nodes that need to join multicast groups MUST support MLDv1 457 [RFC3590]. MLDv1 is needed by any node that is expected to receive 458 and process multicast traffic. Note that Neighbor Discovery (as used 459 on most link types -- see Section 5.2) depends on multicast and 460 requires that nodes join Solicited Node multicast addresses. 462 Nodes that need to join multicast groups SHOULD implement MLDv2 463 [RFC3810]. However, if the node has applications that only need 464 support for Any-Source Multicast [RFC3569], the node MAY implement 465 MLDv1 [RFC2710] instead. If the node has applications that need 466 support for Source-Specific Multicast [RFC3569], [RFC4607], the node 467 MUST support MLDv2 [RFC3810]. In all cases, nodes are strongly 468 encouraged to implement MLDv2 rather than MLDv1, as the presence of a 469 single MLDv1 participant on a link requires that all other nodes on 470 the link operate in version 1 compatibility mode. 472 When MLDv1 is used, the rules in the Source Address Selection for the 473 Multicast Listener Discovery (MLD) Protocol [RFC3590] MUST be 474 followed. 476 6. DHCP vs. Router Advertisement Options for Host Configuration 478 In IPv6, there are two main protocol mechanisms for propagating 479 configuration information to hosts: Router Advertisements and DHCP. 480 Historically, RA options have been restricted to those deemed 481 essential for basic network functioning and for which all nodes are 482 configured with exactly the same information. Examples include the 483 Prefix Information Options, the MTU option, etc. On the other hand, 484 DHCP has generally been preferred for configuration of more general 485 parameters and for parameters that may be client-specific. That 486 said, identifying the exact line on when whether a particular option 487 should be configured via DHCP vs an RA option has not always been 488 easy. Generally speaking, however, there has been a desire to define 489 only one mechanism for configuring a given option, rather than 490 defining multiple (different) ways of configurating the same 491 information. 493 One issue with having multiple ways of configuring the same 494 information is that if a host choses one mechanism, but the network 495 operator chooses a different mechanism, interoperability suffers. 496 For "closed" environments, where the network operator has significant 497 influence over what devices connect to the network and thus what 498 configuration mechanisms they support, the operator may be able to 499 ensure that a particular mechanism is supported by all connected 500 hosts. In more open environments, however, where arbitrary devices 501 may connect (e.g., a WIFI hotspot), problems can arise. To maximize 502 interoperability in such environments hosts may need to implement 503 multiple configuration mechanisms to ensure interoperability. 505 Originally in IPv6, configuring information about DNS servers was 506 performed exclusively via DHCP. In 2007, an RA option was defined, 507 but was published as Experimental [RFC5006]. In 2010, "IPv6 Router 508 Advertisement Options for DNS Configuration" was placed on the 509 Standards Track. Consequently, DNS configuration information can now 510 be learned either through DHCP or through RAs. Hosts will need to 511 decide which mechanism (or whether both) should be implemented. 513 7. DNS and DHCP 515 7.1. DNS 517 DNS is described in [RFC1034], [RFC1035], [RFC3363], and [RFC3596]. 518 Not all nodes will need to resolve names; those that will never need 519 to resolve DNS names do not need to implement resolver functionality. 520 However, the ability to resolve names is a basic infrastructure 521 capability that applications rely on and generally needs to be 522 supported. All nodes that need to resolve names SHOULD implement 523 stub-resolver [RFC1034] functionality, as in RFC 1034, Section 5.3.1, 524 with support for: 526 - AAAA type Resource Records [RFC3596]; 527 - reverse addressing in ip6.arpa using PTR records [RFC3596]; 528 - EDNS0 [RFC2671] to allow for DNS packet sizes larger than 512 529 octets. 531 Those nodes are RECOMMENDED to support DNS security extensions 532 [RFC4033], [RFC4034], and [RFC4035]. 534 Those nodes are NOT RECOMMENDED to support the experimental A6 535 Resource Records [RFC3363]. 537 7.2. Dynamic Host Configuration Protocol for IPv6 (DHCPv6) - RFC 3315 539 7.2.1. Managed Address Configuration 541 DHCP can be used to obtain and configure addresses. In general, a 542 network may provide for the configuration of addresses through RAs, 543 DHCP or both. At the present time, the configuration of stateless 544 address autoconfiguraiton is more widely implemented in hosts than 545 address configuration through DHCP. However, some environments may 546 require the use of DHCP and may not support the configuration of 547 addresses via RAs. Implementations should be aware of what operating 548 environment their devices will be deployed. Hosts MAY implement 549 address configuration via DHCP. 551 In the absence of a router, IPv6 nodes using DHCP for address 552 assignment MAY initiate DHCP to obtain IPv6 addresses and other 553 configuration information, as described in Section 5.5.2 of 554 [RFC4862]. 556 7.2.2. Other Configuration Information 558 IPv6 nodes use DHCP to obtain additional (non-address) configuration. 559 If a host implementation will support applications or other protocols 560 that require configuration that is only available via DHCP, hosts 561 SHOULD implement DHCP. For specialized devices on which no such 562 configuration need is present, DHCP is not necessary. 564 An IPv6 node can use the subset of DHCP (described in [RFC3736]) to 565 obtain other configuration information. 567 7.2.3. Use of Router Advertisements in Managed Environments 569 Nodes using the Dynamic Host Configuration Protocol for IPv6 (DHCPv6) 570 are expected to determine their default router information and on- 571 link prefix information from received Router Advertisements. 573 7.3. IPv6 Router Advertisement Options for DNS Configuration - RFC XXXX 575 Router Advertisements have historically limited options to those that 576 are critical to basic IPv6 functioning. Originally, DNS 577 configuration was not included as an RA option and DHCP was the 578 recommended way to obtain DNS configuration information. Over time, 579 the thinking surrounding such an option has evolved. It is now 580 generally recognized that few nodes can function adequately without 581 having access to a working DNS resolver. RFC 5006 was published as 582 an experimental document in 2007, and recently, a revised version was 583 placed on the Standards Track [I-D.I-D.ietf-6man-dns-options-bis]. 585 Implementations SHOULD implement the DNS RA option. 587 8. IPv4 Support and Transition 589 IPv6 nodes MAY support IPv4. 591 8.1. Transition Mechanisms 593 8.1.1. Basic Transition Mechanisms for IPv6 Hosts and Routers - RFC 594 4213 596 If an IPv6 node implements dual stack and tunneling, then [RFC4213] 597 MUST be supported. 599 9. Mobility 601 Mobile IPv6 [RFC3775] and associated specifications [RFC3776] 602 [RFC4877] allow a node to change its point of attachment within the 603 Internet, while maintaining (and using) a permanent address. All 604 communication using the permanent address continues to proceed as 605 expected even as the node moves around. The definition of Mobile IP 606 includes requirements for the following types of nodes: 608 - mobile nodes 609 - correspondent nodes with support for route optimization 610 - home agents 611 - all IPv6 routers 613 At the present time, Mobile IP has seen only limited implementation 614 and no significant deployment, partly because it originally assumed 615 an IPv6-only environment, rather than a mixed IPv4/IPv6 Internet. 616 Recently, additional work has been done to support mobility in mixed- 617 mode IPv4 and IPv6 networks[RFC5555]. 619 More usage and deployment experience is needed with mobility before 620 any one can be recommended for broad implementation in all hosts and 621 routers. Consequently, [RFC3775], [RFC5555], and associated 622 standards such as [RFC4877] are considered a MAY at this time. 624 10. Security 626 This section describes the specification of IPsec for the IPv6 node. 628 Note: This section needs a rethink. According to RFC4301, IKEv2 MUST 629 be supported. This section cites RFC 4301 as a MUST, yet the 630 remainder of this section only makes IKEv2 a SHOULD. The IPv6 WG has 631 discussed the topic of mandating key management in the past, but has 632 not been willing to make IKE (v1 or v2) a MUST. Is it time to 633 revisit this recommendation? Does it make sense to leave key 634 management as a SHOULD? And what about how that contradicts RFC 635 4301? 637 10.1. Basic Architecture 639 Security Architecture for the Internet Protocol [RFC4301] MUST be 640 supported. 642 10.2. Security Protocols 644 ESP [RFC4303] MUST be supported. AH [RFC4302] MAY be supported. 646 10.3. Transforms and Algorithms 648 The current set of mandatory-to-implement algorithms for ESP and AH 649 are defined in 'Cryptographic Algorithm Implementation Requirements 650 For ESP and AH' [RFC4835]. IPv6 nodes SHOULD conform to the 651 requirements in [RFC4835]. 653 10.4. Key Management Methods 655 An implementation MUST support the manual configuration of the 656 security key and SPI. The SPI configuration is needed in order to 657 delineate between multiple keys. 659 Key management SHOULD be supported. Examples of key management 660 systems include IKEv2 [RFC4306] and Kerberos; S/MIME and TLS include 661 key management functions. 663 Where key refresh, anti-replay features of AH and ESP, or on-demand 664 creation of Security Associations (SAs) is required, automated keying 665 MUST be supported. 667 Key management methods for multicast traffic are also being worked on 668 by the MSEC WG. 670 11. Router-Specific Functionality 672 This section defines general host considerations for IPv6 nodes that 673 act as routers. Currently, this section does not discuss routing- 674 specific requirements. 676 11.1. General 678 11.1.1. IPv6 Router Alert Option - RFC 2711 680 The IPv6 Router Alert Option [RFC2711] is an optional IPv6 Hop-by-Hop 681 Header that is used in conjunction with some protocols (e.g., RSVP 682 [RFC2205] or MLD [RFC2710]). The Router Alert option will need to be 683 implemented whenever protocols that mandate its usage are 684 implemented. See Section 4.6. 686 11.1.2. Neighbor Discovery for IPv6 - RFC 4861 688 Sending Router Advertisements and processing Router Solicitation MUST 689 be supported. 691 12. Network Management 693 Network Management MAY be supported by IPv6 nodes. However, for IPv6 694 nodes that are embedded devices, network management may be the only 695 possible way of controlling these nodes. 697 12.1. Management Information Base Modules (MIBs) 699 The following two MIBs SHOULD be supported by nodes that support an 700 SNMP agent. 702 12.1.1. IP Forwarding Table MIB 704 IP Forwarding Table MIB [RFC4292] SHOULD be supported by nodes that 705 support an SNMP agent. 707 12.1.2. Management Information Base for the Internet Protocol (IP) 709 IP MIB [RFC4293] SHOULD be supported by nodes that support an SNMP 710 agent. 712 13. Open Issues 714 1. The recommendations regarding when to invoke DHCP are 715 problematical with out being able to reference the M&0 bits. 716 2. Security Recommendations needs updating. See note in that 717 Section. 719 14. Security Considerations 721 This document does not directly affect the security of the Internet, 722 but implementations of IPv6 are expected to support a minimum set of 723 security features to ensure security on the Internet. 725 Security is also discussed in Section XXX above. 727 15. Authors and Acknowledgments 729 15.1. Authors and Acknowledgments (Current Document) 731 15.2. Authors and Acknowledgments From RFC 4279 733 The original version of this document (RFC 4279) was written by the 734 IPv6 Node Requirements design team: 736 Jari Arkko 737 jari.arkko@ericsson.com 738 Marc Blanchet 739 marc.blanchet@viagenie.qc.ca 740 Samita Chakrabarti 741 samita.chakrabarti@eng.sun.com 742 Alain Durand 743 alain.durand@sun.com 744 Gerard Gastaud 745 gerard.gastaud@alcatel.fr 746 Jun-ichiro itojun Hagino 747 itojun@iijlab.net 748 Atsushi Inoue 749 inoue@isl.rdc.toshiba.co.jp 750 Masahiro Ishiyama 751 masahiro@isl.rdc.toshiba.co.jp 752 John Loughney 753 john.loughney@nokia.com 754 Rajiv Raghunarayan 755 raraghun@cisco.com 756 Shoichi Sakane 757 shouichi.sakane@jp.yokogawa.com 758 Dave Thaler 759 dthaler@windows.microsoft.com 760 Juha Wiljakka 761 juha.wiljakka@Nokia.com 763 The authors would like to thank Ran Atkinson, Jim Bound, Brian 764 Carpenter, Ralph Droms, Christian Huitema, Adam Machalek, Thomas 765 Narten, Juha Ollila, and Pekka Savola for their comments. Thanks to 766 Mark Andrews for comments and corrections on DNS text. Thanks to 767 Alfred Hoenes for tracking the updates to various RFCs. 769 16. Appendix: Changes from -04 to -05 771 1. Cleaned up IPsec section, but key questions (MUST vs. SHOULD) 772 still open. 774 2. Added background section on DHCP vs. RA options. 776 3. Added SHOULD recomendation for DNS configuration vi RAs 777 (RFC5006bis). 779 4. Cleaned up DHCP section, as it was referring to the M&O bits. 781 5. Cleaned up the Security Considerations Section. 783 17. Appendix: Changes from -03 to -04 785 1. Updated the Introduction to indicate document is an applicabity 786 statement 788 2. Updated the section on Mobility protocols 790 3. Changed Sub-IP Layer Section to just list relevant RFCs, and 791 added some more RFCs. 793 4. Added Section on SEND (make it a MAY) 795 5. Redid Section on Privacy Extensions (RFC4941) to add more nuance 796 to recommendation 798 6. Redid section on Mobility, and added additional RFCs [ 800 18. Appendix: Changes from RFC 4294 802 This appendix keeps track of the chances from RFC 4294 804 1. Section 5.1, removed "and DNAME" from the discussion about RFC- 805 3363. 807 2. RFC 2463 references updated to RFC 4443. 809 3. RFC 3513 references updated to RFC 4291. 811 4. RFC 3152 references updated to RFC 3596. 813 5. RFC 2893 references updated to RFC 4213. 815 6. AH [RFC4302] support chanced from MUST to MAY. 817 7. The reference for RFC 3152 has been deleted, as the RFC has been 818 obsoleted, and has been incorporated into RFC 3596. 820 8. The reference for RFC 3879 has been removed as the material from 821 RFC 3879 has been incorporated into RFC 4291. 823 19. References 825 19.1. Normative References 827 [RFC1035] Mockapetris, P., "Domain names - implementation and 828 specification", STD 13, RFC 1035, November 1987. 830 [RFC1981] McCann, J., Deering, S., and J. Mogul, "Path MTU Discovery 831 for IP version 6", RFC 1981, August 1996. 833 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 834 Requirement Levels", BCP 14, RFC 2119, March 1997. 836 [RFC2460] Deering, S. and R. Hinden, "Internet Protocol, Version 6 837 (IPv6) Specification", RFC 2460, December 1998. 839 [RFC2671] Vixie, P., "Extension Mechanisms for DNS (EDNS0)", 840 RFC 2671, August 1999. 842 [RFC2710] Deering, S., Fenner, W., and B. Haberman, "Multicast 843 Listener Discovery (MLD) for IPv6", RFC 2710, 844 October 1999. 846 [RFC2711] Partridge, C. and A. Jackson, "IPv6 Router Alert Option", 847 RFC 2711, October 1999. 849 [RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C., 850 and M. Carney, "Dynamic Host Configuration Protocol for 851 IPv6 (DHCPv6)", RFC 3315, July 2003. 853 [RFC3363] Bush, R., Durand, A., Fink, B., Gudmundsson, O., and T. 854 Hain, "Representing Internet Protocol version 6 (IPv6) 855 Addresses in the Domain Name System (DNS)", RFC 3363, 856 August 2002. 858 [RFC3484] Draves, R., "Default Address Selection for Internet 859 Protocol version 6 (IPv6)", RFC 3484, February 2003. 861 [RFC3590] Haberman, B., "Source Address Selection for the Multicast 862 Listener Discovery (MLD) Protocol", RFC 3590, 863 September 2003. 865 [RFC3596] Thomson, S., Huitema, C., Ksinant, V., and M. Souissi, 866 "DNS Extensions to Support IP Version 6", RFC 3596, 867 October 2003. 869 [RFC3775] Johnson, D., Perkins, C., and J. Arkko, "Mobility Support 870 in IPv6", RFC 3775, June 2004. 872 [RFC3776] Arkko, J., Devarapalli, V., and F. Dupont, "Using IPsec to 873 Protect Mobile IPv6 Signaling Between Mobile Nodes and 874 Home Agents", RFC 3776, June 2004. 876 [RFC3810] Vida, R. and L. Costa, "Multicast Listener Discovery 877 Version 2 (MLDv2) for IPv6", RFC 3810, June 2004. 879 [RFC4291] Hinden, R. and S. Deering, "IP Version 6 Addressing 880 Architecture", RFC 4291, February 2006. 882 [RFC4292] Haberman, B., "IP Forwarding Table MIB", RFC 4292, 883 April 2006. 885 [RFC4293] Routhier, S., "Management Information Base for the 886 Internet Protocol (IP)", RFC 4293, April 2006. 888 [RFC4301] Kent, S. and K. Seo, "Security Architecture for the 889 Internet Protocol", RFC 4301, December 2005. 891 [RFC4302] Kent, S., "IP Authentication Header", RFC 4302, 892 December 2005. 894 [RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)", 895 RFC 4303, December 2005. 897 [RFC4443] Conta, A., Deering, S., and M. Gupta, "Internet Control 898 Message Protocol (ICMPv6) for the Internet Protocol 899 Version 6 (IPv6) Specification", RFC 4443, March 2006. 901 [RFC4607] Holbrook, H. and B. Cain, "Source-Specific Multicast for 902 IP", RFC 4607, August 2006. 904 [RFC4835] Manral, V., "Cryptographic Algorithm Implementation 905 Requirements for Encapsulating Security Payload (ESP) and 906 Authentication Header (AH)", RFC 4835, April 2007. 908 [RFC4861] Narten, T., Nordmark, E., Simpson, W., and H. Soliman, 909 "Neighbor Discovery for IP version 6 (IPv6)", RFC 4861, 910 September 2007. 912 [RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless 913 Address Autoconfiguration", RFC 4862, September 2007. 915 [RFC4941] Narten, T., Draves, R., and S. Krishnan, "Privacy 916 Extensions for Stateless Address Autoconfiguration in 917 IPv6", RFC 4941, September 2007. 919 [RFC5006] Jeong, J., Park, S., Beloeil, L., and S. Madanapalli, 920 "IPv6 Router Advertisement Option for DNS Configuration", 921 RFC 5006, September 2007. 923 [RFC5072] S.Varada, Haskins, D., and E. Allen, "IP Version 6 over 924 PPP", RFC 5072, September 2007. 926 [RFC5095] Abley, J., Savola, P., and G. Neville-Neil, "Deprecation 927 of Type 0 Routing Headers in IPv6", RFC 5095, 928 December 2007. 930 19.2. Informative References 932 [RFC0793] Postel, J., "Transmission Control Protocol", STD 7, 933 RFC 793, September 1981. 935 [RFC1034] Mockapetris, P., "Domain names - concepts and facilities", 936 STD 13, RFC 1034, November 1987. 938 [RFC2205] Braden, B., Zhang, L., Berson, S., Herzog, S., and S. 939 Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1 940 Functional Specification", RFC 2205, September 1997. 942 [RFC2464] Crawford, M., "Transmission of IPv6 Packets over Ethernet 943 Networks", RFC 2464, December 1998. 945 [RFC2492] Armitage, G., Schulter, P., and M. Jork, "IPv6 over ATM 946 Networks", RFC 2492, January 1999. 948 [RFC2529] Carpenter, B. and C. Jung, "Transmission of IPv6 over IPv4 949 Domains without Explicit Tunnels", RFC 2529, March 1999. 951 [RFC2590] Conta, A., Malis, A., and M. Mueller, "Transmission of 952 IPv6 Packets over Frame Relay Networks Specification", 953 RFC 2590, May 1999. 955 [RFC2675] Borman, D., Deering, S., and R. Hinden, "IPv6 Jumbograms", 956 RFC 2675, August 1999. 958 [RFC3146] Fujisawa, K. and A. Onoe, "Transmission of IPv6 Packets 959 over IEEE 1394 Networks", RFC 3146, October 2001. 961 [RFC3569] Bhattacharyya, S., "An Overview of Source-Specific 962 Multicast (SSM)", RFC 3569, July 2003. 964 [RFC3736] Droms, R., "Stateless Dynamic Host Configuration Protocol 965 (DHCP) Service for IPv6", RFC 3736, April 2004. 967 [RFC3971] Arkko, J., Kempf, J., Zill, B., and P. Nikander, "SEcure 968 Neighbor Discovery (SEND)", RFC 3971, March 2005. 970 [RFC3972] Aura, T., "Cryptographically Generated Addresses (CGA)", 971 RFC 3972, March 2005. 973 [RFC4033] Arends, R., Austein, R., Larson, M., Massey, D., and S. 974 Rose, "DNS Security Introduction and Requirements", 975 RFC 4033, March 2005. 977 [RFC4034] Arends, R., Austein, R., Larson, M., Massey, D., and S. 978 Rose, "Resource Records for the DNS Security Extensions", 979 RFC 4034, March 2005. 981 [RFC4035] Arends, R., Austein, R., Larson, M., Massey, D., and S. 982 Rose, "Protocol Modifications for the DNS Security 983 Extensions", RFC 4035, March 2005. 985 [RFC4213] Nordmark, E. and R. Gilligan, "Basic Transition Mechanisms 986 for IPv6 Hosts and Routers", RFC 4213, October 2005. 988 [RFC4306] Kaufman, C., "Internet Key Exchange (IKEv2) Protocol", 989 RFC 4306, December 2005. 991 [RFC4338] DeSanti, C., Carlson, C., and R. Nixon, "Transmission of 992 IPv6, IPv4, and Address Resolution Protocol (ARP) Packets 993 over Fibre Channel", RFC 4338, January 2006. 995 [RFC4380] Huitema, C., "Teredo: Tunneling IPv6 over UDP through 996 Network Address Translations (NATs)", RFC 4380, 997 February 2006. 999 [RFC4877] Devarapalli, V. and F. Dupont, "Mobile IPv6 Operation with 1000 IKEv2 and the Revised IPsec Architecture", RFC 4877, 1001 April 2007. 1003 [RFC4944] Montenegro, G., Kushalnagar, N., Hui, J., and D. Culler, 1004 "Transmission of IPv6 Packets over IEEE 802.15.4 1005 Networks", RFC 4944, September 2007. 1007 [RFC5121] Patil, B., Xia, F., Sarikaya, B., Choi, JH., and S. 1008 Madanapalli, "Transmission of IPv6 via the IPv6 1009 Convergence Sublayer over IEEE 802.16 Networks", RFC 5121, 1010 February 2008. 1012 [RFC5555] Soliman, H., "Mobile IPv6 Support for Dual Stack Hosts and 1013 Routers", RFC 5555, June 2009. 1015 Authors' Addresses 1017 Ed Jankiewicz 1018 SRI International 1019 Fort Monmouth Branch Office - IPv6 Research 1020 USA 1022 Phone: 1023 Email: ed.jankiewicz@sri.com 1025 John Loughney 1026 Nokia 1027 955 Page Mill Road 1028 Palo Alto 94303 1029 USA 1031 Phone: +1 650 283 8068 1032 Email: john.loughney@nokia.com 1034 Thomas Narten 1035 IBM Corporation 1036 3039 Cornwallis Ave. 1037 PO Box 12195 1038 Research Triangle Park, NC 27709-2195 1039 USA 1041 Phone: +1 919 254 7798 1042 Email: narten@us.ibm.com