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'US-ASCII' -- Obsolete informational reference (is this intentional?): RFC 2673 (Obsoleted by RFC 6891) -- Obsolete informational reference (is this intentional?): RFC 6195 (Obsoleted by RFC 6895) Summary: 4 errors (**), 0 flaws (~~), 3 warnings (==), 6 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 1 INTERNET-DRAFT Donald Eastlake 2 Obsoletes: 6195 Huawei 3 Updates: 1183, 2845, 2930, 3597 4 Intended status: Best Current Practice 5 Expires: January 14, 2013 July 15, 2012 7 Domain Name System (DNS) IANA Considerations 8 10 Abstract 12 This document specifies Internet Assigned Number Authority (IANA) 13 parameter assignment considerations for the allocation of Domain Name 14 System (DNS) resource record types, CLASSes, operation codes, error 15 codes, DNS protocol message header bits, and AFSDB resource record 16 subtypes. It obsoletes RFC 6195 and updates RFCs 1183, 2845, 2930, 17 and 3597. 19 Status of This Memo 21 This Internet-Draft is submitted to IETF in full conformance with the 22 provisions of BCP 78 and BCP 79. 24 Distribution of this draft is unlimited. It is intended to become the 25 new BCP 42 obsoleting RFC 6195. Comments should be sent to the DNS 26 Extensions Working Group mailing list . 28 Internet-Drafts are working documents of the Internet Engineering 29 Task Force (IETF), its areas, and its working groups. Note that 30 other groups may also distribute working documents as Internet- 31 Drafts. 33 Internet-Drafts are draft documents valid for a maximum of six months 34 and may be updated, replaced, or obsoleted by other documents at any 35 time. It is inappropriate to use Internet-Drafts as reference 36 material or to cite them other than as "work in progress." 38 The list of current Internet-Drafts can be accessed at 39 http://www.ietf.org/1id-abstracts.html. The list of Internet-Draft 40 Shadow Directories can be accessed at 41 http://www.ietf.org/shadow.html. 43 Table of Contents 45 1. Introduction............................................3 46 1.1 Terminology............................................3 47 1.2 Acknowledgement........................................3 49 2. DNS Query/Response Headers..............................4 50 2.1 One Spare Bit?.........................................5 51 2.2 OpCode Assignment......................................5 52 2.3 RCODE Assignment.......................................5 54 3. DNS Resource Records....................................8 55 3.1 RRTYPE IANA Considerations.............................9 56 3.1.1 DNS RRTYPE Allocation Policy........................10 57 3.1.2 DNS RRTYPE Expert Guidelines........................11 58 3.1.3 Special Note on the OPT RR..........................11 59 3.1.4 The AFSDB RR Subtype Field..........................12 60 3.2 RR CLASS IANA Considerations..........................12 61 3.3. Label Considerations.................................14 62 3.3.1 Label Types.........................................14 63 3.3.2 Label Contents and Use..............................14 65 4. Security Considerations................................16 66 5. IANA Considerations....................................16 68 Appendix A: RRTYPE Allocation Template....................17 69 Appendix B: Changes From RFC 6195.........................18 71 Normative References......................................19 72 Informative References....................................20 74 1. Introduction 76 The Domain Name System (DNS) provides replicated distributed secure 77 hierarchical databases that store "resource records" (RRs) under 78 domain names. DNS data is structured into CLASSes and zones that can 79 be independently maintained. Familiarity with [RFC1034], [RFC1035], 80 [RFC2136], [RFC2181], and [RFC4033] is assumed. 82 This document provides, either directly or by reference, the general 83 IANA parameter assignment considerations that apply across DNS query 84 and response headers and all RRs. There may be additional IANA 85 considerations that apply to only a particular RRTYPE or 86 query/response OpCode. See the specific RFC defining that RRTYPE or 87 query/response OpCode for such considerations if they have been 88 defined, except for AFSDB RR considerations [RFC1183], which are 89 included herein. This RFC obsoletes [RFC6195]; however, the only 90 significant changes are those to the RRTYPE IANA allocation process, 91 aimed at streamlining it and clarifying the expected behavior of the 92 parties involved, and the closing of the AFSDB sub-type registry. 94 IANA currently maintains a web page of DNS parameters available from 95 http://www.iana.org. 97 1.1 Terminology 99 "Standards Action", "IETF Review", "Specification Required", and 100 "Private Use" are as defined in [RFC5226]. The key words "MUST", 101 "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", 102 "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be 103 interpreted as described in [RFC2119]. 105 1.2 Acknowledgement 107 Alfred Hoenes contributions are gratefully acknowledged as are those 108 by Mark Andrews, Dick Franks, and Michael Sheldon. 110 2. DNS Query/Response Headers 112 The header for DNS queries and responses contains field/bits in the 113 following diagram taken from [RFC2136] and [RFC6195]: 115 1 1 1 1 1 1 116 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 117 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 118 | ID | 119 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 120 |QR| OpCode |AA|TC|RD|RA| Z|AD|CD| RCODE | 121 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 122 | QDCOUNT/ZOCOUNT | 123 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 124 | ANCOUNT/PRCOUNT | 125 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 126 | NSCOUNT/UPCOUNT | 127 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 128 | ARCOUNT | 129 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 131 The ID field identifies the query and is echoed in the response so 132 they can be matched. 134 The QR bit indicates whether the header is for a query or a response. 136 The AA, TC, RD, RA, and CD bits are each theoretically meaningful 137 only in queries or only in responses, depending on the bit. The AD 138 bit was only meaningful in responses but is expected to have a 139 separate but related meaning in queries (see Section 5.7 of 140 [RFCdnssecbisup]). Only the RD and CD bits are expected to be copied 141 from the query to the response; however, some DNS implementations 142 copy all the query header as the initial value of the response 143 header. Thus, any attempt to use a "query" bit with a different 144 meaning in a response or to define a query meaning for a "response" 145 bit may be dangerous, given existing implementation. Meanings for 146 these bits may only be assigned by a Standards Action. 148 The unsigned integer fields query count (QDCOUNT), answer count 149 (ANCOUNT), authority count (NSCOUNT), and additional information 150 count (ARCOUNT) express the number of records in each section for all 151 OpCodes except Update [RFC2136]. These fields have the same structure 152 and data type for Update but are instead the counts for the zone 153 (ZOCOUNT), prerequisite (PRCOUNT), update (UPCOUNT), and additional 154 information (ARCOUNT) sections. 156 2.1 One Spare Bit? 158 There have been ancient DNS implementations for which the Z bit being 159 on in a query meant that only a response from the primary server for 160 a zone is acceptable. It is believed that current DNS implementations 161 ignore this bit. 163 Assigning a meaning to the Z bit requires a Standards Action. 165 2.2 OpCode Assignment 167 Currently, DNS OpCodes are assigned as follows: 169 OpCode Name Reference 171 0 Query [RFC1035] 172 1 IQuery (Inverse Query, Obsolete) [RFC3425] 173 2 Status [RFC1035] 174 3 available for assignment 175 4 Notify [RFC1996] 176 5 Update [RFC2136] 177 6-15 available for assignment 179 Although the Status OpCode is reserved in [RFC1035], its behavior has 180 not been specified. New OpCode assignments require a Standards Action 181 as modified by [RFC4020]. 183 2.3 RCODE Assignment 185 It would appear from the DNS header above that only four bits of 186 RCODE, or response/error code, are available. However, RCODEs can 187 appear not only at the top level of a DNS response but also inside 188 TSIG RRs [RFC2845], TKEY RRs [RFC2930], and extended by OPT RRs 189 [RFC2671bis]. The OPT RR provides an 8-bit extension to the 4 header 190 bits resulting in a 12-bit RCODE field, and the TSIG and TKEY RRs 191 have a 16-bit field designated in their RFCs as the "Error" field. 193 Error codes appearing in the DNS header and in these other RR types 194 all refer to the same error code space with the exception of error 195 code 16, which has a different meaning in the OPT RR than in the TSIG 196 RR, and error code 9 whose variations are described after the table 197 below. The duplicate assignment of 16 was accidental. To the extent 198 that any prior RFCs imply any sort of different error number space 199 for the OPT, TSIG, or TKEY RRs, they are superseded by this unified 200 DNS error number space. (This paragraph is the reason this document 201 updates [RFC2845] and [RFC2930].) With the existing exceptions of 202 error numbers 9 and 16, the same error number MUST NOT be assigned 203 for different errors even if they would only occur in different RR 204 types. See table below. 206 RCODE Name Description Reference 207 Decimal 208 Hexadecimal 210 0 NoError No Error [RFC1035] 211 1 FormErr Format Error [RFC1035] 212 2 ServFail Server Failure [RFC1035] 213 3 NXDomain Non-Existent Domain [RFC1035] 214 4 NotImp Not Implemented [RFC1035] 215 5 Refused Query Refused [RFC1035] 216 6 YXDomain Name Exists when it should not [RFC2136] 217 7 YXRRSet RR Set Exists when it should not [RFC2136] 218 8 NXRRSet RR Set that should exist does not [RFC2136] 219 9 NotAuth See note below after table 220 10 NotZone Name not contained in zone [RFC2136] 222 11 - 15 223 0xB - 0xF Available for assignment 225 16 BADVERS Bad OPT Version [RFC2671bis] 226 16 BADSIG TSIG Signature Failure [RFC2845] 227 17 BADKEY Key not recognized [RFC2845] 228 18 BADTIME Signature out of time window [RFC2845] 229 19 BADMODE Bad TKEY Mode [RFC2930] 230 20 BADNAME Duplicate key name [RFC2930] 231 21 BADALG Algorithm not supported [RFC2930] 232 22 BADTRUC Bad Truncation [RFC4635] 234 23 - 3,840 235 0x0017 - 0x0F00 Available for assignment 237 3,841 - 4,095 238 0x0F01 - 0x0FFF Private Use 240 4,096 - 65,534 241 0x1000 - 0xFFFE Available for assignment 243 65,535 244 0xFFFF Reserved, can only be allocated by a Standards 245 Action. 247 Note on error number 9 (NOTAUTH): This error number means either "Not 248 Authoritative" [RFC2136] or "Not Authorized" [RFC2845]. If 9 249 appears as the RCODE in the header of a DNS response without a 250 TSIG RR or with a TSIG RR having a zero error field, then it means 251 "Not Authoritative". If 9 appears as the RCODE in the header of a 252 DNS response that includes a TSIG RR with a non-zero error field, 253 then it means "Not Authorized". 255 Since it is important that RCODEs be understood for interoperability, 256 assignment of a new RCODE in the ranges listed above as "Available 257 for assignment" requires an IETF Review. 259 3. DNS Resource Records 261 All RRs have the same top-level format, shown in the figure below 262 taken from [RFC1035]. 264 1 1 1 1 1 1 265 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 266 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 267 | | 268 / / 269 / NAME / 270 / / 271 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 272 | TYPE | 273 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 274 | CLASS | 275 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 276 | TTL | 277 | | 278 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 279 | RDLENGTH | 280 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--| 281 / RDATA / 282 / / 283 +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 285 NAME is an owner name, i.e., the name of the node to which this 286 resource record pertains. NAMEs are specific to a CLASS as described 287 in Section 3.2. NAMEs consist of an ordered sequence of one or more 288 labels, each of which has a label type [RFC1035] [RFC2671bis]. 290 TYPE is a 2-octet unsigned integer containing one of the RRTYPE 291 codes. See Section 3.1. 293 CLASS is a 2-octet unsigned integer containing one of the RR CLASS 294 codes. See Section 3.2. 296 TTL is a 4-octet (32-bit) unsigned integer that specifies, for data 297 TYPEs, the number of seconds that the resource record may be cached 298 before the source of the information should again be consulted. Zero 299 is interpreted to mean that the RR can only be used for the 300 transaction in progress. 302 RDLENGTH is an unsigned 16-bit integer that specifies the length in 303 octets of the RDATA field. 305 RDATA is a variable-length string of octets that constitutes the 306 resource. The format of this information varies according to the TYPE 307 and, in some cases, the CLASS of the resource record. 309 3.1 RRTYPE IANA Considerations 311 There are three subcategories of RRTYPE numbers: data TYPEs, QTYPEs, 312 and Meta-TYPEs. 314 Data TYPEs are the means of storing data. QTYPES can only be used in 315 queries. Meta-TYPEs designate transient data associated with a 316 particular DNS message and, in some cases, can also be used in 317 queries. Thus far, data TYPEs have been assigned from 1 upward, plus 318 the block from 100 through 103, and from 32,768 upward, while Q and 319 Meta-TYPEs have been assigned from 255 downward except for the OPT 320 Meta-RR, which is assigned TYPE 41. There have been DNS 321 implementations that made caching decisions based on the top bit of 322 the bottom byte of the RRTYPE. 324 There are currently three Meta-TYPEs assigned: OPT [RFC2671bis], TSIG 325 [RFC2845], and TKEY [RFC2930]. There are currently five QTYPEs 326 assigned: * (ALL/ANY), MAILA, MAILB, AXFR, and IXFR. 328 Allocated RRTYPEs have mnemonics that must be completely disjoint 329 from the mnemonics used for CLASSes and that must match the regular 330 expression below. In addition, the generic CLASS and RRTYPE names 331 specified in Section 5 of [RFC3597] cannot be assigned as new RRTYPE 332 mnemonics. 334 [A-Z][A-Z0-9\-]*[A-Z0-9] 335 but not 336 (TYPE|CLASS)[0-9]* 338 Considerations for the allocation of new RRTYPEs are as follows: 340 Decimal 341 Hexadecimal Assignment Policy 343 0 344 0x0000 RRTYPE zero is used as a special indicator for the 345 SIG (0) RR [RFC2931] [RFC4034] and in other 346 circumstances, and it must never be allocated for 347 ordinary use. 349 1 - 127 350 0x0001 - 0x007F Remaining RRTYPEs in this range are assigned for 351 data TYPEs by the DNS RRTYPE Allocation Policy as 352 specified in Section 3.1.1. 354 128 - 255 355 0x0080 - 0x00FF Remaining RRTYPEs in this range are assigned for Q 356 and Meta-TYPEs by the DNS RRTYPE Allocation Policy 357 as specified in Section 3.1.1. 359 256 - 61,439 360 0x0100 - 0xEFFF Remaining RRTYPEs in this range are assigned for 361 data RRTYPEs by the DNS RRTYPE Allocation Policy as 362 specified in Section 3.1.1. (32,768 and 32,769 363 (0x8000 and 0x8001) have been assigned.) 365 61,440 - 65,279 366 0xF000 - 0xFEFF Reserved for future use. IETF Review required to 367 define use. 369 65,280 - 65,534 370 0xFF00 - 0xFFFE Private Use. 372 65,535 373 0xFFFF Reserved, can only be assigned by a Standards 374 Action. 376 3.1.1 DNS RRTYPE Allocation Policy 378 Parameter values specified in Section 3.1 above as assigned based on 379 DNS RRTYPE Allocation Policy, are allocated by Expert Review if they 380 meet the two requirements listed below. There will be a pool of a 381 small number of Experts appointed by the IESG. Each application will 382 be judged by an Expert selected by IANA. In any case where the 383 selected Expert is unavailable or states they have a conflict of 384 interest, IANA may select another Expert from the pool. Some 385 guidelines for the Experts are given in Section 3.1.2. 387 RRTYPEs that do not meet the requirements below may nonetheless be 388 allocated by a Standards Action as modified by [RFC4020]. 390 1. A complete template as specified in Appendix A has been posted to 391 the dns-rrtype-applications@ietf.org mailing list and received by 392 the Expert. 393 Note that the posting of partially completed, draft, or 394 formally submitted templates to dnsext@ietf.org by the applicant 395 or Expert for comment and discussion is highly encouraged. Formal 396 submission of an RRTYPE template without consideration of some 397 community review can be expected to increase the probability of 398 initial rejection leading to a need to re-submit after 399 modification. 401 2. The RR for which an RRTYPE code is being requested is either (a) a 402 data TYPE that can be handled as an Unknown RR as described in 403 [RFC3597] or (b) a Meta-TYPE whose processing is optional, i.e., 404 it is safe to simply discard RRs with that Meta-TYPE in queries or 405 responses. 406 Note that such RRs may include additional section processing, 408 provided such processing is optional. 410 After the applicant submits their formal application to IANA by 411 sending the completed template specified in Appendix A to the dns- 412 rrtype-applications@ietf.org mailing list, IANA appoints an Expert 413 and sends the completed template to the Expert copying the applicant. 414 No more than two weeks after receiving the application the Expert 415 shall explicitly approve or reject the application, informing IANA, 416 the applicant, and the dnsext@ietf.org mailing list. The Expert 417 should consult with other technical experts and the dnsext@ietf.org 418 mailing list as necessary. If the Expert does not approve the 419 application within this period, it is considered rejected. IANA 420 should report non-responsive Experts to the IESG. 422 IANA shall maintain a public archive of approved templates. In 423 addition, if the required description of the RRTYPE applied for is 424 referenced by URL, a copy of the document so referenced should be 425 included in the archive. 427 3.1.2 DNS RRTYPE Expert Guidelines 429 The Expert should normally reject any RRTYPE allocation request that 430 meets one or more of the following criteria: 432 1. Was documented in a manner that was not sufficiently clear or 433 complete to evaluate or implement. (Additional documentation can 434 be provided during the Expert review period.) 436 2. The proposed RRTYPE or RRTYPEs affect DNS processing and do not 437 meet the criteria in point 2 of Section 3.1.1 above. 439 3. Application use as documented makes incorrect assumptions about 440 DNS protocol behavior, such as wild cards, CNAME, DNAME, etc. 442 4. An excessive number of RRTYPE values is being requested when the 443 purpose could be met with a smaller number or with Private Use 444 values. 446 3.1.3 Special Note on the OPT RR 448 The OPT (OPTion) RR (RRTYPE 41) and its IANA considerations are 449 specified in [RFC2671bis]. Its primary purpose is to extend the 450 effective field size of various DNS fields including RCODE, label 451 type, OpCode, flag bits, and RDATA size. In particular, for resolvers 452 and servers that recognize it, it extends the RCODE field from 4 to 453 12 bits. 455 3.1.4 The AFSDB RR Subtype Field 457 The AFSDB RR [RFC1183] is a CLASS-insensitive RR that has the same 458 RDATA field structure as the MX RR [RFC1035], but the 16-bit unsigned 459 integer field at the beginning of the RDATA is interpreted as a 460 subtype as shown below. Use of the AFSDB RR to locate AFS cell 461 database servers was deprecated by [RFC5864]. This subtype registry 462 is hereby closed and allocation of new subtypes is no longer 463 permitted. 465 Decimal 466 Hexadecimal Assignment Policy 468 0 469 0x0000 Reserved, registry closed 471 1 472 0x0001 AFS v3.0 Location Service [RFC1183] 474 2 475 0x0002 DCE/NCA root cell directory node [RFC1183] 477 3 - 65,279 478 0x0003 - 0xFEFF Not allocated, registry closed 480 65,280 - 65,534 481 0xFF00 - 0xFFFE Private Use 483 65,535 484 0xFFFF Reserved, registry closed 486 3.2 RR CLASS IANA Considerations 488 There are currently two subcategories of DNS CLASSes: normal, data- 489 containing classes and QCLASSes that are only meaningful in queries 490 or updates. 492 DNS CLASSes have been little used but constitute another dimension of 493 the DNS distributed database. In particular, there is no necessary 494 relationship between the name space or root servers for one data 495 CLASS and those for another data CLASS. The same DNS NAME can have 496 completely different meanings in different CLASSes. The label types 497 are the same, and the null label is usable only as root in every 498 CLASS. As global networking and DNS have evolved, the IN, or 499 Internet, CLASS has dominated DNS use. 501 As yet, there has not been a requirement for "meta-CLASSes". That 502 would be a CLASS to designate transient data associated with a 503 particular DNS message, which might be usable in queries. However, it 504 is possible that there might be a future requirement for one or more 505 "meta-CLASSes". 507 Assigned CLASSes have mnemonics that must be completely disjoint from 508 the mnemonics used for RRTYPEs and that must match the regular 509 expression below. In addition, the generic CLASS and RRTYPE names 510 specified in Section 5 of [RFC3597] cannot be assigned as new CLASS 511 mnemonics. 513 [A-Z][A-Z0-9\-]*[A-Z0-9] 514 but not 515 (CLASS|RRTYPE)[0-9]* 517 The current CLASS assignments and considerations for future 518 assignments are as follows: 520 Decimal 521 Hexadecimal Assignment / Policy, Reference 523 0 524 0x0000 Reserved; assignment requires a Standards Action 526 1 527 0x0001 Internet (IN) [RFC1035] 529 2 530 0x0002 Available for assignment by IETF Review as a data 531 CLASS 533 3 534 0x0003 Chaos (CH) [Moon1981] 536 4 537 0x0004 Hesiod (HS) [Dyer1987] 539 5 - 127 540 0x0005 - 0x007F Available for assignment by IETF Review for data 541 CLASSes only 543 128 - 253 544 0x0080 - 0x00FD Available for assignment by IETF Review for 545 QCLASSes and meta-CLASSes only 547 254 548 0x00FE QCLASS NONE [RFC2136] 550 255 551 0x00FF QCLASS * (ANY) [RFC1035] 552 256 - 32,767 553 0x0100 - 0x7FFF Available for assignment by IETF Review 555 32,768 - 57,343 556 0x8000 - 0xDFFF Available for assignment to data CLASSes only; 557 Specification Required 559 57,344 - 65,279 560 0xE000 - 0xFEFF Available for assignment to QCLASSes and meta- 561 CLASSes only; Specification Required 563 65,280 - 65,534 564 0xFF00 - 0xFFFE Private Use 566 65,535 567 0xFFFF Reserved; can only be assigned by a Standards 568 Action 570 3.3. Label Considerations 572 DNS NAMEs are sequences of labels [RFC1035]. 574 3.3.1 Label Types 576 At the present time, there are two categories of label types: data 577 labels and compression labels. Compression labels are pointers to 578 data labels elsewhere within an RR or DNS message and are intended to 579 shorten the wire encoding of NAMEs. 581 The two existing data label types are sometimes referred to as Text 582 and Binary. Text labels can, in fact, include any octet value 583 including zero-value octets, but many current uses involve only 584 printing ASCII characters [US-ASCII]. For retrieval, Text labels are 585 defined to treat ASCII upper and lower case letter codes as matching 586 [RFC4343]. Binary labels are bit sequences [RFC2673]. The Binary 587 label type is Historic [RFC2671bis]. 589 3.3.2 Label Contents and Use 591 The last label in each NAME is "ROOT", which is the zero-length 592 label. By definition, the null or ROOT label cannot be used for any 593 other NAME purpose. 595 NAMEs are local to a CLASS. The Hesiod [Dyer1987] and Chaos 597 [Moon1981] CLASSes are for essentially local use. The IN, or 598 Internet, CLASS is thus the only DNS CLASS in global use on the 599 Internet at this time. 601 A somewhat out-of-date description of name allocation in the IN Class 602 is given in [RFC1591]. Some information on reserved top-level domain 603 names is in BCP 32 [RFC2606]. 605 4. Security Considerations 607 This document addresses IANA considerations in the allocation of 608 general DNS parameters, not security. See [RFC4033], [RFC4034], and 609 [RFC4035] for secure DNS considerations. 611 5. IANA Considerations 613 This document consists entirely of DNS IANA Considerations. 615 IANA has established a process for accepting Appendix A templates and 616 selecting an Expert from those appointed to review such template form 617 applications. IANA forwards the template to the Expert copying the 618 applicant. IANA archives and makes available all approved RRTYPE 619 allocation templates and referred documentation (unless it is readily 620 available at a stable URI). It is the duty of the applicant to post 621 the formal application template to the dns-rrtype- 622 applications@ietf.org mailing list, which IANA will monitor. The 623 dnsext@ietf.org mailing list is for community discussion and comment. 624 See Section 3.1 and Appendix A for more details. 626 Appendix A: RRTYPE Allocation Template 628 DNS RRTYPE PARAMETER ALLOCATION TEMPLATE 630 When ready for formal consideration, this template is to be submitted 631 to IANA for processing by emailing the template to dns-rrtype- 632 applications@ietf.org. 634 A. Submission Date: 636 B.1 Submission Type: [ ] New RRTYPE [ ] Modification to RRTYPE 637 B.2 Kind of RR: [ ] Data RR [ ] Meta-RR 639 C. Contact Information for submitter (will be publicly posted): 640 Name: 641 Email Address: 642 International telephone number: 643 Other contact handles: 645 D. Motivation for the new RRTYPE application. 646 Please keep this part at a high level to inform the Expert and 647 reviewers about uses of the RRTYPE. Most reviewers will be DNS 648 experts that may have limited knowledge of your application space. 650 E. Description of the proposed RR type. 651 This description can be provided in-line in the template, as an 652 attachment, or with a publicly available URL. 654 F. What existing RRTYPE or RRTYPEs come closest to filling that need 655 and why are they unsatisfactory? 657 G. What mnemonic is requested for the new RRTYPE (optional)? 658 Note: this can be left blank and the mnemonic decided after the 659 template is accepted. 661 H. Does the requested RRTYPE make use of any existing IANA registry 662 or require the creation of a new IANA sub-registry in DNS 663 Parameters? If so, please indicate which registry is to be used 664 or created. If a new sub-registry is needed, specify the 665 allocation policy for it and its initial contents. Also include 666 what the modification procedures will be. 668 I. Does the proposal require/expect any changes in DNS 669 servers/resolvers that prevent the new type from being processed 670 as an unknown RRTYPE (see [RFC3597])? 672 J. Comments: 674 Appendix B: Changes From RFC 6195 676 Drop description of changes from RFC 5395 to [RFC6195] since those 677 changes have already happened and we don't need to do them again. Add 678 description of changes from [RFC6195] to this document. 680 Cut back RRTYPE Expert review period to two weeks and eliminate the 681 mandatory dnsext@ietf.org comment period. Change workflow description 682 for RRTYPE review and allocation to correspond more closely to actual 683 practice. 685 Close the AFSDB sub-type registry and add an informative reference to 686 [RFC5864] where the use of the AFSDB RR to locate AFS cell database 687 servers is deprecated. 689 Clarify IANA archiving of referenced documentation as well as 690 approved RRTYPE application template. 692 In the RRTYPE application template, change the label of question "B" 693 to "B.1" and add "B.2" to ask about the kind of RR. 695 Addition of text and an exclusory regular expression to Sections 3.1 696 and 3.2 to prohibit the use of a slight generalization of the generic 697 CLASS and RRTYPE names specified in [RFC3597] as the mnemonics for 698 new CLASSes and RRTYPEes. 700 Parenthetically list "ANY" and well as "ALL" as a meaning for the "*" 701 RRTYPE. 703 Clarify that there is one DNS error number space for headers, OPT 704 extended headers, TSIG RRs, and TKEY RRs. Note that this can be 705 considered to update [RFC2845] and [RFC2930]. Note the overloading of 706 error number 9 as well as 16. 708 Update references for revised versions. 710 A number of editorial changes and typo fixes. 712 Normative References 714 [RFC1034] - Mockapetris, P., "Domain names - concepts and 715 facilities", STD 13, RFC 1034, November 1987. 717 [RFC1035] - Mockapetris, P., "Domain names - implementation and 718 specification", STD 13, RFC 1035, November 1987. 720 [RFC1996] - Vixie, P., "A Mechanism for Prompt Notification of Zone 721 Changes (DNS NOTIFY)", RFC 1996, August 1996. 723 [RFC2119] - Bradner, S., "Key words for use in RFCs to Indicate 724 Requirement Levels", BCP 14, RFC 2119, March 1997 726 [RFC2136] - Vixie, P., Ed., Thomson, S., Rekhter, Y., and J. Bound, 727 "Dynamic Updates in the Domain Name System (DNS UPDATE)", 728 RFC 2136, April 1997. 730 [RFC2181] - Elz, R. and R. Bush, "Clarifications to the DNS 731 Specification", RFC 2181, July 1997. 733 [RFC2845] - Vixie, P., Gudmundsson, O., Eastlake 3rd, D., and B. 734 Wellington, "Secret Key Transaction Authentication for 735 DNS (TSIG)", RFC 2845, May 2000. 737 [RFC2930] - Eastlake 3rd, D., "Secret Key Establishment for DNS (TKEY 738 RR)", RFC 2930, September 2000. 740 [RFC3425] - Lawrence, D., "Obsoleting IQUERY", RFC 3425, November 741 2002. 743 [RFC3597] - Gustafsson, A., "Handling of Unknown DNS Resource Record 744 (RR) Types", RFC 3597, September 2003. 746 [RFC4020] - Kompella, K. and A. Zinin, "Early IANA Allocation of 747 Standards Track Code Points", BCP 100, RFC 4020, February 748 2005. 750 [RFC4033] - Arends, R., Austein, R., Larson, M., Massey, D., and S. 751 Rose, "DNS Security Introduction and Requirements", RFC 752 4033, March 2005. 754 [RFC4034] - Arends, R., Austein, R., Larson, M., Massey, D., and S. 755 Rose, "Resource Records for the DNS Security Extensions", 756 RFC 4034, March 2005. 758 [RFC4035] - Arends, R., Austein, R., Larson, M., Massey, D., and S. 759 Rose, "Protocol Modifications for the DNS Security 760 Extensions", RFC 4035, March 2005. 762 [RFC4635] - Eastlake 3rd, D., "HMAC SHA (Hashed Message 763 Authentication Code, Secure Hash Algorithm) TSIG 764 Algorithm Identifiers", RFC 4635, August 2006. 766 [RFC5226] - Narten, T. and H. Alvestrand, "Guidelines for Writing an 767 IANA Considerations Section in RFCs", BCP 26, RFC 5226, 768 May 2008. 770 [RFC2671bis] - Damas, J., Graff, M., and Vixie, P., "Extension 771 Mechanisms for DNS (EDNS0)", draft-ietf-dnsext- 772 rfc2671bis-edns0, work in progress. 774 [RFCdnssecbisup] - Weiler, A. and D. Blacka, "Clarifications and 775 Implementation Notes for DNSSECbis", draft-ietf-dnsext- 776 dnssec-bis-updates, work in progress. 778 [US-ASCII] - American National Standards Institute (formerly United 779 States of America Standards Institute), "USA Code for 780 Information Interchange", ANSI X3.4-1968, 1968. ANSI 781 X3.4-1968 has been replaced by newer versions with slight 782 modifications, but the 1968 version remains definitive 783 for the Internet. 785 Informative References 787 [Dyer1987] - Dyer, S., and F. Hsu, "Hesiod", Project Athena Technical 788 Plan - Name Service, April 1987. 790 [Moon1981] - Moon, D., "Chaosnet", A.I. Memo 628, Massachusetts 791 Institute of Technology Artificial Intelligence 792 Laboratory, June 1981. 794 [RFC1183] - Everhart, C., Mamakos, L., Ullmann, R., and P. 795 Mockapetris, "New DNS RR Definitions", RFC 1183, October 796 1990. 798 [RFC1591] - Postel, J., "Domain Name System Structure and 799 Delegation", RFC 1591, March 1994. 801 [RFC2606] - Eastlake 3rd, D. and A. Panitz, "Reserved Top Level DNS 802 Names", BCP 32, RFC 2606, June 1999. 804 [RFC2673] - Crawford, M., "Binary Labels in the Domain Name System", 805 RFC 2673, August 1999. 807 [RFC2931] - Eastlake 3rd, D., "DNS Request and Transaction Signatures 808 ( SIG(0)s )", RFC 2931, September 2000. 810 [RFC4343] - Eastlake 3rd, D., "Domain Name System (DNS) Case 811 Insensitivity Clarification", RFC 4343, January 2006. 813 [RFC5864] - Allbery, R., "DNS SRV Resource Records for AFS", RFC 814 5864, April 2010. 816 [RFC6195] - Eastlake 3rd, D., "Domain Name System (DNS) IANA 817 Considerations", RFC 6195, March 2011. 819 Author's Address 821 Donald E. Eastlake 3rd 822 Huawei R&D USA 823 155 Beaver Street 824 Milford, MA 01757 USA 826 Telephone: +1-508-333-2270 827 email: d3e3e3@gmail.com 829 Copyright and IPR Provisions 831 Copyright (c) 2012 IETF Trust and the persons identified as the 832 document authors. All rights reserved. 834 This document is subject to BCP 78 and the IETF Trust's Legal 835 Provisions Relating to IETF Documents 836 (http://trustee.ietf.org/license-info) in effect on the date of 837 publication of this document. Please review these documents 838 carefully, as they describe your rights and restrictions with respect 839 to this document. Code Components extracted from this document must 840 include Simplified BSD License text as described in Section 4.e of 841 the Trust Legal Provisions and are provided without warranty as 842 described in the Simplified BSD License.