idnits 2.17.1 draft-ietf-dime-4over6-provisioning-02.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- == There are 1 instance of lines with non-RFC6890-compliant IPv4 addresses in the document. If these are example addresses, they should be changed. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document date (June 2, 2015) is 3251 days in the past. Is this intentional? Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Outdated reference: A later version (-18) exists of draft-ietf-softwire-dslite-multicast-09 == Outdated reference: A later version (-15) exists of draft-ietf-softwire-multicast-prefix-option-08 -- Obsolete informational reference (is this intentional?): RFC 3315 (Obsoleted by RFC 8415) Summary: 0 errors (**), 0 flaws (~~), 4 warnings (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Internet Engineering Task Force C. Zhou 3 Internet-Draft Huawei Technologies 4 Intended status: Standards Track T. Taylor 5 Expires: December 4, 2015 PT Taylor Consulting 6 Q. Sun 7 China Telecom 8 M. Boucadair 9 France Telecom 10 June 2, 2015 12 Attribute-Value Pairs For Provisioning Customer Equipment Supporting 13 IPv4-Over-IPv6 Transitional Solutions 14 draft-ietf-dime-4over6-provisioning-02 16 Abstract 18 During the transition from IPv4 to IPv6, customer equipment may have 19 to support one of the various transition methods that have been 20 defined for carrying IPv4 packets over IPv6. This document 21 enumerates the information that needs to be provisioned on a customer 22 edge router to support a list of transition techniques based on 23 tunneling IPv4 in IPv6, with a view to defining reusable components 24 for a reasonable transition path between these techniques. To the 25 extent that the provisioning is done dynamically, AAA support is 26 needed to provide the information to the network server responsible 27 for passing the information to the customer equipment. This document 28 specifies Diameter (RFC 6733) attribute-value pairs to be used for 29 that purpose. 31 Status of This Memo 33 This Internet-Draft is submitted in full conformance with the 34 provisions of BCP 78 and BCP 79. 36 Internet-Drafts are working documents of the Internet Engineering 37 Task Force (IETF). Note that other groups may also distribute 38 working documents as Internet-Drafts. The list of current Internet- 39 Drafts is at http://datatracker.ietf.org/drafts/current/. 41 Internet-Drafts are draft documents valid for a maximum of six months 42 and may be updated, replaced, or obsoleted by other documents at any 43 time. It is inappropriate to use Internet-Drafts as reference 44 material or to cite them other than as "work in progress." 46 This Internet-Draft will expire on December 4, 2015. 48 Copyright Notice 50 Copyright (c) 2015 IETF Trust and the persons identified as the 51 document authors. All rights reserved. 53 This document is subject to BCP 78 and the IETF Trust's Legal 54 Provisions Relating to IETF Documents 55 (http://trustee.ietf.org/license-info) in effect on the date of 56 publication of this document. Please review these documents 57 carefully, as they describe your rights and restrictions with respect 58 to this document. Code Components extracted from this document must 59 include Simplified BSD License text as described in Section 4.e of 60 the Trust Legal Provisions and are provided without warranty as 61 described in the Simplified BSD License. 63 Table of Contents 65 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 66 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 4 67 2. Description of the Parameters Required By Each Transition 68 Method . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 69 2.1. Parameters For Dual-Stack Lite (DS-Lite) . . . . . . . . 5 70 2.2. Lightweight IPv4 Over IPv6 (LW4over6) . . . . . . . . . . 5 71 2.3. Port Set Specification . . . . . . . . . . . . . . . . . 5 72 2.4. Mapping of Address and Port with Encapsulation (MAP-E) . 6 73 2.5. Parameters For Multicast . . . . . . . . . . . . . . . . 7 74 2.6. Summary and Discussion . . . . . . . . . . . . . . . . . 8 75 3. Attribute-Value Pair Definitions . . . . . . . . . . . . . . 8 76 3.1. IP-Prefix-Length AVP . . . . . . . . . . . . . . . . . . 8 77 3.2. Border-Router-Name AVP . . . . . . . . . . . . . . . . . 9 78 3.3. 64-Multicast-Attributes AVP . . . . . . . . . . . . . . . 9 79 3.3.1. ASM-Prefix64 AVP . . . . . . . . . . . . . . . . . . 9 80 3.3.2. SSM-Prefix64 AVP . . . . . . . . . . . . . . . . . . 10 81 3.3.3. Delegated-IPv6-Prefix AVP As uPrefix64 . . . . . . . 10 82 3.4. Tunnel-Source-Pref-Or-Addr AVP . . . . . . . . . . . . . 10 83 3.4.1. Delegated-IPv6-Prefix As the IPv6 Binding Prefix . . 11 84 3.4.2. Tunnel-Source-IPv6-Address AVP . . . . . . . . . . . 11 85 3.5. Port-Set-Identifier . . . . . . . . . . . . . . . . . . . 11 86 3.6. LW4over6-Binding . . . . . . . . . . . . . . . . . . . . 12 87 3.7. MAP-E-Attributes . . . . . . . . . . . . . . . . . . . . 12 88 3.8. MAP-Mapping-Rule . . . . . . . . . . . . . . . . . . . . 13 89 3.8.1. Rule-IPv4-Addr-Or-Prefix AVP . . . . . . . . . . . . 14 90 3.8.2. Rule-IPv6-Prefix AVP . . . . . . . . . . . . . . . . 14 91 3.8.3. EA-Field-Length AVP . . . . . . . . . . . . . . . . . 15 92 3.8.4. Port-Set-Identifier AVP . . . . . . . . . . . . . . . 15 93 4. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 15 94 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15 95 6. Security Considerations . . . . . . . . . . . . . . . . . . . 16 96 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 16 97 7.1. Normative References . . . . . . . . . . . . . . . . . . 16 98 7.2. Informative References . . . . . . . . . . . . . . . . . 17 99 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18 101 1. Introduction 103 A number of transition technologies have been defined to allow IPv4 104 packets to pass between hosts and IPv4 networks over an intervening 105 IPv6 network while minimizing the number of public IPv4 addresses 106 that need to be consumed by the hosts. Different operators will 107 deploy different technologies, and sometimes one operator will use 108 more than one technology, depending on what is supported by the 109 available equipment and upon other factors both technical and 110 economic. 112 Each technique requires the provisioning of some subscriber-specific 113 information on the customer edge device. The provisioning may be by 114 DHCPv6 [RFC3315] or by some other method. This document is 115 indifferent to the specific provisioning technique used, but assumes 116 a deployment in which that information is managed by AAA 117 (Authentication, Authorization, and Accounting) servers. It further 118 assumes that this information is delivered to intermediate network 119 nodes for onward provisioning using the Diameter protocol [RFC6733]. 121 As described below, in the particular case where the Lightweight IPv4 122 Over IPv6 (Lw4o6) [I-D.ietf-softwire-lw4over6] transition method has 123 been deployed, per-subscriber-site information almost identical to 124 that passed to the subscriber site [I-D.ietf-softwire-map-dhcp] also 125 needs to be delivered to the border router serving that site. The 126 Diameter protocol may be used for this purpose too. 128 This document analyzes the information required to configure the 129 customer edge equipment for the following set of transition methods: 131 o Dual-Stack Lite (DS-Lite) [RFC6333], 133 o Lightweight IPv4 Over IPv6 (LW4over6) 134 [I-D.ietf-softwire-lw4over6], and 136 o Mapping of Address and Port with Encapsulation (MAP-E) 137 [I-D.ietf-softwire-map]. 139 [I-D.ietf-softwire-dslite-multicast] specifies a generic solution for 140 delivery of IPv4 multicast services to IPv4 clients over an IPv6 141 multicast network. The solution was developed with DS-Lite in mind 142 but it is however not limited to DS-Lite. As such, it applies also 143 for LW4over6 and MAP-E. This document analyzes the information 144 required to configure the customer edge equipment for the support of 145 multicast in the context of DS-Lite, MAP, and LW4over6 in particular. 147 On the basis of those analyses it specifies a number of attribute- 148 value pairs (AVPs) to allow the necessary subscriber-site-specific 149 configuration information to be carried in Diameter. 151 This document doesn't specify any new commands or Application-Ids and 152 that the AVPs could be used for any Diameter application suitable for 153 provisioning. 155 1.1. Requirements Language 157 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 158 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 159 document are to be interpreted as described in [RFC2119]. 161 The abbreviation "CE" denotes the equipment at the customer edge that 162 terminates the customer end of an IPv6 transitional tunnel. This 163 will usually be a router, but could be a host directly connected to 164 the network. 166 The term "tunnel source address" is used to denote the IPv6 source 167 address used in the outer header of packets sent from the CE through 168 an LW4over6 transitional tunnel to the border router. 170 2. Description of the Parameters Required By Each Transition Method 172 This section reviews the parameters that need to be provisioned for 173 each of the transition methods listed above. This enumeration 174 provides the justification for the AVPs defined in the next section. 176 A means is required to indicate which transition method(s) a given 177 subscriber is allowed to use. The approach taken in this document is 178 to specify grouped AVPs specific to LW4over6 and MAP-E. The operator 179 can control which of these two transition methods a given subscriber 180 uses by ensuring that AAA passes only the grouped AVP relevant to 181 that method. A grouped AVP is unnecessary for Dual-Stack Lite, since 182 (as the next section indicates) AAA has to provide only one 183 parameter. Hence the absence of either of the grouped AVPs indicates 184 that the subscriber equipment will use Dual-Stack Lite. Provisioning 185 of multicast is an orthogonal activity, since it is independent of 186 the transition method. 188 2.1. Parameters For Dual-Stack Lite (DS-Lite) 190 DS-Lite is documented in [RFC6333]. The Basic Bridging BroadBand 191 (B4) element at the customer premises needs to be provisioned with 192 the IPv6 address of the AFTR (border router). Optionally, it could 193 also be configured with the IPv4 address of the B4 interface facing 194 the tunnel, where the default value in the absence of provisioning is 195 192.0.0.2 and valid values are 192.0.0.2 through 192.0.0.7. 196 Provisioning this information through AAA is problematic because it 197 is most likely used in a case where multiple B4 instances occupy the 198 same device. This document therefore assumes that the B4 interface 199 address is determined by other means (implementation-dependent or 200 static assignment). 202 2.2. Lightweight IPv4 Over IPv6 (LW4over6) 204 Light Weight IPv4 Over IPv6 (LW4over6) is documented in 205 [I-D.ietf-softwire-lw4over6]. LW4over6 requires four items to be 206 provisioned to the customer equipment: 208 o IPv6 address of the border router. 210 o IPv6 prefix used by the CE to construct the tunnel source address. 211 In the terminology of [I-D.ietf-softwire-lw4over6], this is the 212 IPv6 Binding Prefix. 214 o an IPv4 address to be used on the external side of the CE; and 216 o if the IPv4 address is shared, a specification of the port set the 217 subscriber site is allowed to use. Please see the description in 218 Section 2.3. For LW4over6, all three of the parameters 'a', 'k', 219 and PSID described in that section are required. The default 220 value of the offset parameter 'a' is 0. 222 As discussed in Section 4 of [I-D.ietf-softwire-lw4over6], it is 223 necessary to synchronize this configuration with corresponding per- 224 subscriber configuration at the border router. The border router 225 information consists of the same public IPv4 address and port set 226 parameters that are passed to the CE, bound together with the full 227 /128 IPv6 address (not just the Binding Prefix) configured as the 228 tunnel source address at the CE. 230 2.3. Port Set Specification 232 When an external IPv4 address is shared, LW4over6 and MAP-E restrict 233 the CE to use of a subset of all available ports on the external 234 side. Both transition methods use the algorithm defined in 235 Appendix B of [I-D.ietf-softwire-map] to derive the values of the 236 port numbers in the port set. This algorithm features three 237 parameters, describing the positioning and value of the Port Set 238 Identifier (PSID) within each port number of the generated set: 240 o an offset 'a' from the beginning of the port number to the first 241 bit of the PSID; 243 o the length 'k' of the PSID within the port number, in bits; and 245 o the value of the PSID itself. 247 2.4. Mapping of Address and Port with Encapsulation (MAP-E) 249 Mapping of Address and Port with Encapsulation (MAP-E) is described 250 in [I-D.ietf-softwire-map]. MAP-E requires the provisioning of the 251 following per-subscriber information at the customer edge device: 253 o the IPv6 address of one or more border routers, or in MAP-E 254 terminology, MAP border relays. 256 o the unique End-user IPv6 prefix for the customer edge device. 257 This may be provided by AAA or acquired by other means. 259 o the Basic Mapping Rule for the customer edge device. This 260 includes the following parameters: 262 * the rule IPv6 prefix and length; 264 * the rule IPv4 prefix and length. A prefix length of 0 265 indicates that the entire IPv4 address or prefix is coded in 266 the Extended Address (EA) bits of the End-user IPv6 prefix 267 rather than in the mapping rule. 269 * the number of EA bits included in the End-user IPv6 prefix; 271 * port set parameters giving the set of ports the CE is allowed 272 to use when the IPv4 address is shared. Please see the 273 description of these parameters in Section 2.3. At a minimum, 274 the offset parameter 'a' is required. For MAP-E this has the 275 default value 6. The parameters 'k' and PSID are needed if 276 they cannot be derived from the mapping rule information and 277 the EA bits (final case of Section 5.2 of 278 [I-D.ietf-softwire-map]). 280 o whether the device is to operate in mesh or hub-and-spoke mode; 282 o in mesh mode only, zero or more Forwarding Mapping Rules, 283 described by the same set of parameters as the Basic Mapping Rule; 285 As indicated in Section 5, bullet 1 of the MAP-E document, a MAP CE 286 can be provisioned with multiple End-user IPv6 prefixes, each 287 associated with its own Basic Mapping Rule. This does not change the 288 basic requirement for representation of the corresponding information 289 in the form of Diameter AVPs, but adds a potential requirement for 290 multiple instances of this information to be present in the Diameter 291 message, differing in the value of the End-user IPv6 prefix (in 292 contrast to the Forward Mapping Rule instances). 294 The border router needs to be configured with the superset of the 295 Mapping Rules passed to the customer sites it serves. Since this 296 requirement does not require direct coordination with CE 297 configuration in the way LW4over6 does, it is out of scope of the 298 present document. However, the AVPs defined here may be useful if a 299 separate Diameter application is used to configure the border router. 301 2.5. Parameters For Multicast 303 [I-D.ietf-softwire-dslite-multicast] specifies a generic solution for 304 delivery of IPv4 multicast services to IPv4 clients over an IPv6 305 multicast network. The solution can be in particular deployed in a 306 DS-Lite context, but is also adaptable to LW4over6 and MAP-E. For 307 example, [I-D.ietf-softwire-multicast-prefix-option] specifies how 308 DHCPv6 [RFC3315] can be used to provision multicast-related 309 information. The following lists the multicast-related information 310 that needs to be provisioned: 312 o ASM_mPrefix64: the IPv6 multicast prefix to be used to synthesize 313 the IPv4-embedded IPv6 addresses of the multicast groups in the 314 Any-Source Multicast (ASM) mode. This is achieved by 315 concatenating the ASM_mPrefix64 and a IPv4 multicast address; the 316 Pv4 multicast address is inserted in the last 32 bits of the 317 IPv4-embedded IPv6 multicast address. 319 o SSM_mPrefix64: the IPv6 multicast prefix to be used to synthesize 320 the IPv4-embedded IPv6 addresses of the multicast groups in the 321 Source-Specific Multicast (SSM, [RFC4607]) mode. This is achieved 322 by concatenating the SSM_mPrefix64 and a IPv4 multicast address; 323 the Pv4 multicast address is inserted in the last 32 bits of the 324 IPv4-embedded IPv6 multicast address. 326 o uPrefix64: the IPv6 unicast prefix to be used in SSM mode for 327 constructing the IPv4-embedded IPv6 addresses representing the 328 IPv4 multicast sources in the IPv6 domain. uPrefix64 may also be 329 used to extract the IPv4 address from the received multicast data 330 flows. The address mapping follows the guidelines documented in 331 [RFC6052]. 333 2.6. Summary and Discussion 335 It appears that two items are common to the different transition 336 methods and the corresponding AVPs to carry them can be reused: 338 o a representation of the IPv6 address of a border router; 340 o A set of prefixes for delivery of multicast services to IPv4 341 clients over an IPv6 multicast network. 343 [RFC6519] sets a precedent for representation of the IPv6 address of 344 a border router as an FQDN. This can be dereferenced to one or more 345 IP addresses by the provisioning system before being passed to the 346 customer equipment, or left as an FQDN as it as in [RFC6334]. 348 The remaining requirements are transition-method-specific: 350 o for LW4over6, a representation of a binding between (1) either the 351 IPv6 Binding Prefix or a full /128 IPv6 address, (2) a public IPv4 352 address, and (3) (if the IPv4 address is shared) a port set 353 identifier; 355 o for MAP-E, a representation of the unique End-user IPv6 prefix for 356 the CE, if not provided by other means; 358 o for MAP-E, a representation of a Mapping Rule; 360 o for MAP-E, an indication of whether mesh mode or hub-and-spoke 361 mode is to be used. 363 3. Attribute-Value Pair Definitions 365 This section provides the specifications for the AVPs needed to meet 366 the requirements summarized in Section 2.6. Within the context of 367 their usage, all of these AVPs MUST have the M bit set and the V bit 368 cleared. 370 3.1. IP-Prefix-Length AVP 372 The IP-Prefix-Length AVP (AVP code TBD00) is of type Unsignedint. It 373 provides the length of an IPv4 or IPv6 prefix. Valid values are from 374 0 to 32 for IPv4, and from 0 to 128 for IPv6. Tighter limits are 375 given below for particular contexts of use of this AVP. 377 3.2. Border-Router-Name AVP 379 Following on the precedent set by [RFC6334] and [RFC6519], this 380 document identifies a border router using an FQDN rather than an 381 address. The Border-Router-Name AVP (AVP Code TBD01) is of type 382 OctetString. The rules for encoding the FQDN are the same as those 383 for the FQDN variant of the derived type DiameterIdentity 384 (Section 4.3.1 of [RFC6733]). 386 3.3. 64-Multicast-Attributes AVP 388 The 64-Multicast-Attributes AVP (AVP Code TBD02) is of type Grouped. 389 It contains the multicast-related prefixes needed for providing IPv4 390 multicast over IPv6 using DS-Lite, MAP-E, or LW4over6, as mentioned 391 in Section 2.5. 393 The syntax is shown in Figure 1. 395 64-Multicast-Attributes ::= < AVP Header: TBD02 > 396 [ ASM-Prefix64 ] 397 [ SSM-Prefix64 ] 398 [ Delegated-IPv6-Prefix ] 399 *[ AVP ] 401 Figure 1: 64-Multicast-Attributes AVP 403 If either ASM-Prefix64 or SSM-Prefix64 or both are present, 404 Delegated-IPv6-Prefix MUST also be present. 406 3.3.1. ASM-Prefix64 AVP 408 The ASM-Prefix64 AVP (AVP Code TBD03) conveys the value of 409 ASM_mPrefix64 as mentioned in Section 2.5. The ASM-Prefix64 AVP is 410 of type Grouped, as shown in Figure 2. 412 ASM-Prefix64 ::= < AVP Header: TBD03 > 413 { IP-Address } 414 { IP-Prefix-Length } 415 *[ AVP ] 417 Figure 2: ASM-Prefix64 AVP 419 IP-Address (AVP code 518) is defined in [RFC5777] and is of type 420 Address. Within the ASM-Prefix64 AVP, it provides the value of an 421 IPv6 prefix. The AddressType field in IP-Address MUST have value 2 422 (IPv6). The conveyed multicast IPv6 prefix MUST belong to the ASM 423 range. Unused bits in IP-Address beyond the actual prefix MUST be 424 set to zeroes by the sender and ignored by the receiver. 426 The IP-Prefix-Length AVP provides the actual length of the prefix 427 contained in the IP-Address AVP. Within the ASM-Prefix64 AVP, valid 428 values of the IP-Prefix-Length AVP are from 24 to 96. 430 3.3.2. SSM-Prefix64 AVP 432 The SSM-Prefix64 AVP (AVP Code TBD04) conveys the value of 433 SSM_mPrefix64 as mentioned in Section 2.5. The SSM-Prefix64 AVP is 434 of type Grouped, as shown in Figure 3. 436 SSM-Prefix64 ::= < AVP Header: TBD04 > 437 { IP-Address } 438 { IP-Prefix-Length } 439 *[ AVP ] 441 Figure 3: SSM-Prefix64 AVP 443 IP-Address (AVP code 518) provides the value of an IPv6 prefix. The 444 AddressType field in IP-Address MUST have value 2 (IPv6). The 445 conveyed multicast IPv6 prefix MUST belong to the SSM range. Unused 446 bits in IP-Address beyond the actual prefix MUST be set to zeroes by 447 the sender and ignored by the receiver. 449 The IP-Prefix-Length AVP provides the actual length of the prefix 450 contained in the IP-Address AVP. With regard to prefix length, note 451 that Section 6 of [RFC3306] requires that bits 33-95 of an SSM 452 address in the FF3x range be set to zero, meaning that the prefix 453 length for an SSM prefix is effectively 96. However, Section 1 of 454 [RFC4607] suggests that the lower limit of 32 bits be preserved to 455 allow potential future use of bits 33-95. Hence applications SHOULD 456 accept prefix lengths between 32 and 96 inclusive. 458 3.3.3. Delegated-IPv6-Prefix AVP As uPrefix64 460 Within the 64-Multicast-Attributes AVP, the Delegated-IPv6-Prefix AVP 461 (AVP Code 123) conveys the value of uPrefix64, a unicast IPv6 prefix, 462 as mentioned in Section 2.5. The Delegated-IPv6-Prefix AVP is 463 defined in [RFC4818]. As specified by [RFC6052], the value in the 464 Prefix-Length field MUST be one of 32, 48, 56, 64 or 96. 466 3.4. Tunnel-Source-Pref-Or-Addr AVP 468 The Tunnel-Source-Pref-Or-Addr AVP (AVP Code TBD05) conveys either 469 the IPv6 Binding Prefix or the tunnel source address on the CE, as 470 described in Section 2.2. The Tunnel-Source-Pref-Or-Addr AVP is of 471 type Grouped, with syntax as shown in Figure 4. One of the 472 Delegated-IPv6-Prefix AVP or the Tunnel-Source-IPv6-Address AVP MUST 473 be present. 475 Tunnel-Source-Pref-Or-Addr ::= < AVP Header: TBD05 > 476 [ Delegated-IPv6-Prefix ] 477 [ Tunnel-Source-IPv6-Address ] 478 *[ AVP ] 480 Figure 4: Tunnel-Source-Pref-Or-Addr AVP 482 This AVP is defined separately from the LW4over6-Binding AVP (which 483 includes it) to provide flexibility in the transport of the tunnel 484 source address from the provisioning system to AAA while also 485 supporting the provision of a complete binding to the LW4over6 border 486 router. 488 3.4.1. Delegated-IPv6-Prefix As the IPv6 Binding Prefix 490 The Delegated-IPv6-Prefix AVP (AVP code 123) is of type Octetstring, 491 and is defined in [RFC4818]. Within the Tunnel-Source-Pref-Or-Addr 492 AVP, it conveys the IPv6 Binding Prefix assigned to the CE. Valid 493 values in the Prefix-Length field are from 0 to 128 (full address), 494 although a more restricted range is obviously more reasonable. 496 3.4.2. Tunnel-Source-IPv6-Address AVP 498 The Tunnel-Source-IPv6-Address AVP (AVP code TBD06) is of type 499 Address. It provides the address that the CE has assigned to its end 500 of an LW4over6 tunnel. The AddressType field in this AVP MUST be set 501 to 2 (IPv6). 503 3.5. Port-Set-Identifier 505 The Port-Set-Identifier AVP (AVP Code TBD07) is a structured 506 OctetString with four octets of data, hence a total AVP length of 12. 507 The description of the structure which follows refers to refers to 508 the parameters described in Section 2.3. 510 o The first (high-order) octet is the Offset field. It is 511 interpreted as an 8-bit unsigned integer giving the offset 'a' 512 from the beginning of a port number to the beginning of the port 513 set identifier (PSID) to which that port belongs. Valid values 514 are from 0 to 15. 516 o The next octet, the PSIDLength, is also interpreted as an 8-bit 517 unsigned integer and gives the length 'k' in bits of the port set 518 identifier (PSID). Valid values are from 0 to (16 - a). A value 519 of 0 indicates that the PSID is not present (probable case for 520 MAP-E, see Section 2.4), and the PSIDValue field MUST be ignored. 522 o The final two octets contain the PSIDValue field. They give the 523 value of the PSID itself, right-justified within the field. That 524 is, the value of the PSID occupies the 'k' lowest-order bits of 525 the PSIDValue field. 527 3.6. LW4over6-Binding 529 The LW4over6-Binding AVP (AVP Code TBD08) is of type Grouped. It 530 contains the elements of configuration that constitute the binding 531 between an LW4over6 tunnel and IPv4 packets sent through that tunnel, 532 as described in Section 2.2. 534 LW4over6-Binding ::= < AVP Header: TBD08 > 535 { Tunnel-Source-Pref-Or-Addr } 536 { LW4over6-External-IPv4-Addr } 537 [ Port-Set-Identifier ] 538 *[ AVP ] 540 Figure 5 542 The Tunnel-Source-Pref-Or-Addr AVP is defined in Section 3.4 and 543 provides either the Binding Prefix or the full IPv6 tunnel source 544 address. This AVP MUST be present. 546 The LW4over6-External-IPv4-Addr AVP (AVP Code TBD09) uses the Address 547 derived data format defined in Section 4.3.1 of [RFC6733]. It 548 provides the CE's external IPv4 address within the LW4over6 tunnel 549 associated with the given binding. The AddressType field MUST be set 550 to 1 (IPv4), and the total length of the AVP MUST be 14 octets. This 551 AVP MUST be present. 553 The Port-Set-Identifier AVP is defined in Section 3.5. It identifies 554 the specific set of ports assigned to the LW4over6 tunnel, when the 555 IPv4 address is being shared. 557 3.7. MAP-E-Attributes 559 The MAP-E-Attributes AVP (AVP Code TBD10) is of type Grouped. It 560 contains the configuration data identified in Section 2.4 for all of 561 the mapping rules (Basic and Forwarding) in a single MAP domain. 562 Multiple instances of this AVP will be present if the CE belongs to 563 multiple MAP domains. 565 MAP-E-Attributes ::= < AVP Header: TBD06 > 566 1*{ Border-Router-Name } 567 1*{ MAP-Mapping-Rule } 568 [ MAP-Mesh-Mode ] 569 [ Delegated-IPv6-Prefix ] 570 *[ AVP ] 572 Figure 6 574 The Border-Router-Name AVP is defined in Section 3.2. It provides 575 the FQDN of a MAP border relay at the edge of the MAP domain to which 576 the containing MAP-E-Attributes AVP relates. At least one instance 577 of this AVP MUST be present. 579 The MAP-Mapping-Rule AVP is defined in Section 3.8. At least one 580 instance of this AVP MUST be present. If the MAP-E domain supports 581 mesh mode (indicated by the presence of the MAP-Mesh-Mode AVP), 582 additional MAP-Mapping-Rule instances MAY be present. If the MAP-E 583 domain is operating in hub-and-spoke mode, additional MAP-Mapping- 584 Rule instances MUST NOT be present. 586 The MAP-Mesh-Mode AVP (AVP Code TBD11) uses the OctetString data 587 format but has no data. Hence the AVP length is always 8. The 588 absence of the mesh mode indicator attribute indicates that the CE is 589 required to operate in hub-and-spoke mode. 591 The Delegated-IPv6-Prefix AVP (AVP Code 123) provides the End-user 592 IPv6 prefix assigned to the CE for the MAP domain to which the 593 containing MAP-E-Attributes AVP relates. The AVP is defined in 594 [RFC4818]. Valid values of the Prefix-Length field range from 0 to 595 128. 597 The Delegated-IPv6-Prefix AVP is optional because, depending on 598 deployment, the End-user IPv6 prefix may be provided by AAA or by 599 other means. If multiple instances of the MAP-E-Attributes AVP 600 containing the Delegated-IPv6-Prefix AVP are present, each instance 601 of the latter MUST have a different value. 603 3.8. MAP-Mapping-Rule 605 The MAP-Mapping-Rule AVP (AVP Code TBD12) is of type Grouped, and is 606 used only in conjunction with MAP-based transition methods. Mapping 607 rules are required both by the MAP border relay and by the CE. The 608 components of the MAP-Mapping-Rule AVP provide the contents of a 609 mapping rule as described in Section 2.4. 611 The syntax of the MAP-Mapping-Rule AVP is as follows: 613 MAP-Mapping-Rule ::= < AVP Header: TBD12 > 614 { Rule-IPv4-Addr-Or-Prefix } 615 { Rule-IPv6-Prefix } 616 { EA-Field-Length } 617 { Port-Set-Identifier } 618 *[ AVP ] 620 Figure 7 622 The Rule-IPv4-Addr-Or-Prefix, Rule-IPv6-Prefix, EA-Field-Length, and 623 Port-Set-Identifier AVPs MUST all be present. 625 3.8.1. Rule-IPv4-Addr-Or-Prefix AVP 627 The Rule-IPv4-Addr-Or-Prefix AVP (AVP Code TBD13) conveys the rule 628 IPv4 prefix and length as described in Section 2.4. The Rule-IPv4- 629 Addr-Or-Prefix AVP is of type Grouped, as shown in Figure 8. 631 Rule-IPv4-Addr-Or-Prefix ::= < AVP Header: TBD13 > 632 { IP-Address } 633 { IP-Prefix-Length } 634 *[ AVP ] 636 Figure 8: Rule-IPv4-Addr-Or-Prefix AVP 638 IP-Address (AVP code 518) is defined in [RFC5777] and is of type 639 Address. Within the Rule-IPv4-Addr-Or-Prefix AVP, it provides the 640 value of a unicast IPv4 address or prefix. The AddressType field in 641 IP-Address MUST have value 1 (IPv4). Unused bits in IP-Address 642 beyond the actual prefix MUST be set to zeroes by the sender and 643 ignored by the receiver. 645 The IP-Prefix-Length AVP provides the actual length of the prefix 646 contained in the IP-Address AVP. Within the Rule-IPv4-Addr-Or-Prefix 647 AVP, valid values of the IP-Prefix-Length AVP are from 0 to 32 (full 648 address), based on the different cases identified in Section 5.2 of 649 [I-D.ietf-softwire-map]. 651 3.8.2. Rule-IPv6-Prefix AVP 653 The Rule-IPv6-Prefix AVP (AVP Code TBD14) conveys the rule IPv6 654 prefix and length as described in Section 2.4. The Rule-IPv6-Prefix 655 AVP is of type Grouped, as shown in Figure 9. 657 Rule-IPv6-Prefix ::= < AVP Header: TBD14 > 658 { IP-Address } 659 { IP-Prefix-Length } 660 *[ AVP ] 662 Figure 9: Rule-IPv6-Prefix AVP 664 IP-Address (AVP code 518) is defined in [RFC5777] and is of type 665 Address. Within the Rule-IPv6-Prefix AVP, it provides the value of a 666 unicast IPv6 prefix. The AddressType field in IP- Address MUST have 667 value 2 (IPv6). Unused bits in IP-Address beyond the actual prefix 668 MUST be set to zeroes by the sender and ignored by the receiver. 669 This AVP MUST be present. 671 The IP-Prefix-Length AVP provides the actual length of the prefix 672 contained in the IP-Address AVP. Within the Rule-IPv6-Prefix AVP, 673 the minimum valid prefix length is 0. The maximum value is bounded 674 by the length of the End-user IPv6 prefix associated with the mapping 675 rule, if present in the form of the Delegated-IPv6-Prefix AVP in the 676 enclosing MAP-E-Attributes AVP. Otherwise the maximum value is 128. 677 This AVP MUST be present. 679 3.8.3. EA-Field-Length AVP 681 The EA-Field-Length AVP (AVP Code TBD15) is of type Unsigned32. 682 Valid values range from 0 to 48. See Section 5.2 of 683 [I-D.ietf-softwire-map] for a description of the use of this 684 parameter in deriving IPv4 address and port number configuration. 685 This AVP MUST be present. 687 3.8.4. Port-Set-Identifier AVP 689 The Port-Set-Identifier AVP provides information to identify the 690 specific set of ports assigned to the CE. For more information see 691 Section 2.4 and Section 2.3. The Port-Set-Identifier AVP is defined 692 in Section 3.5. It MUST be present. 694 4. Acknowledgements 696 Huawei Technologies funded Tom Taylor's work on earlier versions of 697 this document. 699 5. IANA Considerations 701 This memo requests to IANA to register the following Diameter AVP 702 codes: 704 +-------+-----------------------------+---------------+ 705 | Code | Attribute Name | Reference | 706 +-------+-----------------------------+---------------+ 707 | TBD00 | IP-Prefix-Length | This document | 708 | TBD01 | Border-Router-Name | This document | 709 | TBD02 | 64-Multicast-Attributes | This document | 710 | TBD03 | ASM-Prefix64 | This document | 711 | TBD04 | SSM-Prefix64 | This document | 712 | TBD05 | Tunnel-Source-Pref-Or-Addr | This document | 713 | TBD06 | Tunnel-Source-IPv6-Address | This document | 714 | TBD07 | Port-Set-Identifier | This document | 715 | TBD08 | LW4over6-Binding | This document | 716 | TBD09 | LW4over6-External-IPv4-Addr | This document | 717 | TBD10 | MAP-E-Attributes | This document | 718 | TBD11 | MAP-Mesh-Mode | This document | 719 | TBD12 | MAP-Mapping-Rule | This document | 720 | TBD13 | Rule-IPv4-Addr-Or-Prefix | This document | 721 | TBD14 | Rule-IPv6-Prefix | This document | 722 | TBD15 | EA-Field-Length | This document | 723 +-------+-----------------------------+---------------+ 725 Table 1 727 6. Security Considerations 729 The AVPs defined in this document face two threats, both dependent on 730 man-in-the-middle attacks on the Diameter delivery path. The more 731 serious threat is denial of service through modification of the AVP 732 contents leading to misconfiguration. The lesser threat is 733 disclosure of subscriber addresses allowing the attacker to track 734 subscriber activity. 736 Diameter security is currently provided on a hop-by-hop basis (see 737 Section 2.2 of [RFC6733]). The Diameter end-to-end security problem 738 has not been solved, so man-in-the-middle attacks on Diameter peers 739 along the path are possible. The present document does not propose 740 to solve that general problem, but simply warn that it exists. 742 7. References 744 7.1. Normative References 746 [I-D.ietf-softwire-lw4over6] 747 Cui, Y., Sun, Q., Boucadair, M., Tsou, T., Lee, Y., and I. 748 Farrer, "Lightweight 4over6: An Extension to the DS-Lite 749 Architecture (work in progress)", March 2014. 751 [I-D.ietf-softwire-map] 752 Troan, O., Dec, W., Li, X., Bao, C., Matsushima, S., 753 Murakami, T., and T. Taylor, "Mapping of Address and Port 754 with Encapsulation (MAP) (work in progress)", January 755 2014. 757 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 758 Requirement Levels", BCP 14, RFC 2119, March 1997. 760 [RFC3306] Haberman, B. and D. Thaler, "Unicast-Prefix-based IPv6 761 Multicast Addresses", RFC 3306, August 2002. 763 [RFC4818] Salowey, J. and R. Droms, "RADIUS Delegated-IPv6-Prefix 764 Attribute", RFC 4818, April 2007. 766 [RFC5777] Korhonen, J., Tschofenig, H., Arumaithurai, M., Jones, M., 767 and A. Lior, "Traffic Classification and Quality of 768 Service (QoS) Attributes for Diameter", RFC 5777, February 769 2010. 771 [RFC6333] Durand, A., Droms, R., Woodyatt, J., and Y. Lee, "Dual- 772 Stack Lite Broadband Deployments Following IPv4 773 Exhaustion", RFC 6333, August 2011. 775 [RFC6733] Fajardo, V., Arkko, J., Loughney, J., and G. Zorn, 776 "Diameter Base Protocol", RFC 6733, October 2012. 778 7.2. Informative References 780 [I-D.ietf-softwire-dslite-multicast] 781 Qin, J., Boucadair, M., Jacquenet, C., Lee, Y., and Q. 782 Wang, "Delivery of IPv4 Multicast Services to IPv4 Clients 783 over an IPv6 Multicast Network", draft-ietf-softwire- 784 dslite-multicast-09 (work in progress), March 2015. 786 [I-D.ietf-softwire-map-dhcp] 787 Mrugalski, T., Troan, O., Farrer, I., Perrault, S., Dec, 788 W., Bao, C., Yeh, L., and X. Deng, "DHCPv6 Options for 789 configuration of Softwire Address and Port Mapped Clients 790 (Work in progress)", March 2014. 792 [I-D.ietf-softwire-multicast-prefix-option] 793 Boucadair, M., Qin, J., Tsou, T., and X. Deng, "DHCPv6 794 Option for IPv4-Embedded Multicast and Unicast IPv6 795 Prefixes", draft-ietf-softwire-multicast-prefix-option-08 796 (work in progress), March 2015. 798 [RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C., 799 and M. Carney, "Dynamic Host Configuration Protocol for 800 IPv6 (DHCPv6)", RFC 3315, July 2003. 802 [RFC4607] Holbrook, H. and B. Cain, "Source-Specific Multicast for 803 IP", RFC 4607, August 2006. 805 [RFC6052] Bao, C., Huitema, C., Bagnulo, M., Boucadair, M., and X. 806 Li, "IPv6 Addressing of IPv4/IPv6 Translators", RFC 6052, 807 October 2010. 809 [RFC6334] Hankins, D. and T. Mrugalski, "Dynamic Host Configuration 810 Protocol for IPv6 (DHCPv6) Option for Dual-Stack Lite", 811 RFC 6334, August 2011. 813 [RFC6519] Maglione, R. and A. Durand, "RADIUS Extensions for Dual- 814 Stack Lite", RFC 6519, February 2012. 816 Authors' Addresses 818 Cathy Zhou 819 Huawei Technologies 820 Bantian, Longgang District 821 Shenzhen 518129 822 P.R. China 824 Email: cathy.zhou@huawei.com 826 T. Taylor 827 PT Taylor Consulting 828 Ottawa 829 Canada 831 Email: tom.taylor.stds@gmail.com 833 Qiong Sun 834 China Telecom 835 P.R.China 837 Phone: 86 10 58552936 838 Email: sunqiong@ctbri.com.cn 839 M. Boucadair 840 France Telecom 841 Rennes 35000 842 France 844 Email: mohamed.boucadair@orange.com