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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group M. Cotton 3 Internet-Draft ICANN 4 BCP: 26 B. Leiba 5 Obsoletes: 5226 (if approved) Huawei Technologies 6 Intended status: Best Current Practice T. Narten 7 Expires: September 28, 2013 IBM Corporation 8 March 29, 2013 10 Guidelines for Writing an IANA Considerations Section in RFCs 11 draft-leiba-cotton-iana-5226bis-02 13 Abstract 15 Many protocols make use of points of extensibility that use constants 16 to identify various protocol parameters. To ensure that the values 17 used in these fields do not have conflicting uses, and to promote 18 interoperability, their allocation is often coordinated by a central 19 authority. For IETF protocols, that role is filled by the Internet 20 Assigned Numbers Authority (IANA). 22 To manage a given namespace prudently, IANA needs guidance describing 23 the conditions under which new values should be assigned, as well as 24 when and how modifications to existing values can be made. This 25 document defines a framework for the documentation of these 26 guidelines by specification authors, in order to assure that the 27 guidance given to IANA is clear and addresses the various issues that 28 are likely in the operation of a registry. 30 This is the third edition, and obsoletes RFC 5226. 32 Status of this Memo 34 This Internet-Draft is submitted in full conformance with the 35 provisions of BCP 78 and BCP 79. 37 Internet-Drafts are working documents of the Internet Engineering 38 Task Force (IETF). Note that other groups may also distribute 39 working documents as Internet-Drafts. The list of current Internet- 40 Drafts is at http://datatracker.ietf.org/drafts/current/. 42 Internet-Drafts are draft documents valid for a maximum of six months 43 and may be updated, replaced, or obsoleted by other documents at any 44 time. It is inappropriate to use Internet-Drafts as reference 45 material or to cite them other than as "work in progress." 47 This Internet-Draft will expire on September 28, 2013. 49 Copyright Notice 51 Copyright (c) 2013 IETF Trust and the persons identified as the 52 document authors. All rights reserved. 54 This document is subject to BCP 78 and the IETF Trust's Legal 55 Provisions Relating to IETF Documents (http://trustee.ietf.org/ 56 license-info) in effect on the date of publication of this document. 57 Please review these documents carefully, as they describe your rights 58 and restrictions with respect to this document. Code Components 59 extracted from this document must include Simplified BSD License text 60 as described in Section 4.e of the Trust Legal Provisions and are 61 provided without warranty as described in the Simplified BSD License. 63 Table of Contents 65 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 66 1.1. Terminology Used In This Document . . . . . . . . . . . . 3 67 2. Creating and Revising Registries . . . . . . . . . . . . . . . 3 68 2.1. Documentation Requirements for Registries . . . . . . . . 4 69 2.2. Defining an Appropriate Registry Policy . . . . . . . . . 6 70 2.2.1. Using the Well-Known Registration Policies . . . . . . 8 71 2.2.2. Using Multiple Policies in Combination . . . . . . . . 9 72 2.3. Revising Existing Registries . . . . . . . . . . . . . . . 10 73 3. Registering New Values in an Existing Registry . . . . . . . . 10 74 3.1. Documentation Requirements for Registrations . . . . . . . 10 75 3.2. Updating Existing Registrations . . . . . . . . . . . . . 12 76 3.3. Overriding Registration Procedures . . . . . . . . . . . . 12 77 4. Well-Known Registration Policies . . . . . . . . . . . . . . . 13 78 4.1. Private Use . . . . . . . . . . . . . . . . . . . . . . . 13 79 4.2. Experimental Use . . . . . . . . . . . . . . . . . . . . . 14 80 4.3. Hierarchical Allocation . . . . . . . . . . . . . . . . . 14 81 4.4. First Come First Served . . . . . . . . . . . . . . . . . 14 82 4.5. Expert Review . . . . . . . . . . . . . . . . . . . . . . 15 83 4.6. Specification Required . . . . . . . . . . . . . . . . . . 15 84 4.7. RFC Required . . . . . . . . . . . . . . . . . . . . . . . 16 85 4.8. IETF Review . . . . . . . . . . . . . . . . . . . . . . . 16 86 4.9. Standards Action . . . . . . . . . . . . . . . . . . . . . 16 87 4.10. IESG Approval . . . . . . . . . . . . . . . . . . . . . . 17 88 5. Designated Experts . . . . . . . . . . . . . . . . . . . . . . 17 89 5.1. The Motivation for Designated Experts . . . . . . . . . . 17 90 5.2. The Role of the Designated Expert . . . . . . . . . . . . 18 91 5.3. Designated Expert Reviews . . . . . . . . . . . . . . . . 19 92 5.4. Expert Reviews and the Document Lifecycle . . . . . . . . 21 93 6. Well-Known Registration Status Terminology . . . . . . . . . . 21 94 7. Documentation References in IANA Registries . . . . . . . . . 22 95 8. What to Do in "bis" Documents . . . . . . . . . . . . . . . . 22 96 9. Miscellaneous Issues . . . . . . . . . . . . . . . . . . . . . 23 97 9.1. When There Are No IANA Actions . . . . . . . . . . . . . . 23 98 9.2. Namespaces Lacking Documented Guidance . . . . . . . . . . 24 99 9.3. After-the-Fact Registrations . . . . . . . . . . . . . . . 24 100 9.4. Reclaiming Assigned Values . . . . . . . . . . . . . . . . 25 101 9.5. Contact Person vs Assignee or Owner . . . . . . . . . . . 25 102 9.6. Closing or Obsoleting a Registry . . . . . . . . . . . . . 26 103 9.7. BCP 78/79 Issues in Registries . . . . . . . . . . . . . . 26 104 10. Appeals . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 105 11. Mailing Lists . . . . . . . . . . . . . . . . . . . . . . . . 26 106 12. Security Considerations . . . . . . . . . . . . . . . . . . . 26 107 13. To-Do List; resolve and remove before requesting publication . 27 108 14. Changes Relative to Earlier Editions of BCP 26 . . . . . . . . 27 109 14.1. 2013: Changes in This Document Relative to RFC 5226 . . . 27 110 14.2. 2008: Changes in RFC 5226 Relative to RFC 2434 . . . . . 28 111 15. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 28 112 15.1. Acknowledgments for This Document (2013) . . . . . . . . 28 113 15.2. Acknowledgments from the second edition (2008) . . . . . 29 114 15.3. Acknowledgments from the first edition (1998) . . . . . . 29 115 16. References . . . . . . . . . . . . . . . . . . . . . . . . . . 29 116 16.1. Normative References . . . . . . . . . . . . . . . . . . 29 117 16.2. Informative References . . . . . . . . . . . . . . . . . 29 118 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 32 120 1. Introduction 122 Many protocols make use of points of extensibility that use constants 123 to identify various protocol parameters. To ensure that the values 124 used in these fields do not have conflicting uses, and to promote 125 interoperability, their allocation is often coordinated by a central 126 authority. For IETF protocols, that role is filled by the Internet 127 Assigned Numbers Authority (IANA) [RFC2860]. 129 The Protocol field in the IP header [RFC0791] and MIME media types 130 [RFC4288] are two examples of such coordinations. 132 In this document, we call the range of possible values for such a 133 field a "namespace". The binding or association of a specific value 134 with a particular purpose within a namespace is called an assignment 135 (or, variously: an assigned number, assigned value, "code point", 136 "protocol constant", or "protocol parameter"). The act of assignment 137 is called a registration, and it takes place in the context of a 138 registry. 140 To manage a given namespace prudently, IANA needs guidance describing 141 the conditions under which new values should be assigned, as well as 142 when and how modifications to existing values can be made. This 143 document defines a framework for the documentation of these 144 guidelines by specification authors, in order to assure that the 145 guidance given to IANA is clear and addresses the various issues that 146 are likely in the operation of a registry. 148 Typically, this information is recorded in a dedicated section of the 149 specification with the title "IANA Considerations". 151 1.1. Terminology Used In This Document 153 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 154 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 155 document are to be interpreted as described in RFC 2119 [RFC2119]. 156 For this document, "the specification" as used by RFC 2119 refers to 157 the processing of protocol documents within the IETF standards 158 process. 160 2. Creating and Revising Registries 161 Defining a registry involves describing the namespace(s) to be 162 created, listing an initial set of assignments (if appropriate), and 163 documenting guidelines on how future assignments are to be made. 165 Before defining a registry, however, consider delegating the 166 namespace in some manner. This route should be pursued when 167 appropriate, as it lessens the burden on IANA for dealing with 168 assignments. 170 In particular, not all namespaces require a registry; in some cases, 171 assignments can be made independently and with no further (central) 172 coordination. In the Domain Name System, for example, IANA only 173 deals with assignments at the higher levels, while subdomains are 174 administered by the organization to which the space has been 175 delegated. When a namespace is delegated in this manner, the scope 176 of IANA is limited to the parts of the namespace where IANA has 177 authority. 179 2.1. Documentation Requirements for Registries 181 Documents that create a new namespace (or modify the definition of an 182 existing space) and that expect IANA to play a role in maintaining 183 that space (serving as a repository for registered values) MUST 184 provide clear instructions on details of the namespace, either in the 185 IANA Considerations section, or referenced from it. 187 In particular, such instructions MUST include: 189 The name of the registry (or sub-registry) 190 This name will appear on the IANA web page and will be referred to 191 in future documents that need to allocate a value from the new 192 space. The full name (and abbreviation, if appropriate) should be 193 provided. It is highly desirable that the chosen name not be 194 easily confused with the name of another registry. 196 When creating a sub-registry, the registry that it is a part of 197 must be identified using its full name, exactly as it appears in 198 the IANA registry list. 200 Providing a URL to precisely identify the registry helps IANA 201 understand the request. Such URLs are usually removed from the 202 RFC prior to final publication. 204 For example, a document could contain something like this: 206 [TO BE REMOVED: This registration should be made in the Foobar 207 Operational Parameters registry, located at http://www.iana.org 208 /assignments/foobar-registry] 210 Required information for registrations 212 This information may include the need to document relevant 213 Security Considerations, if any. 215 Applicable review process 217 The review process that will apply to all future requests for 218 registration. See Section 2.2. 220 Size, format and syntax of registry entries 222 What fields to record in the registry., and any technical 223 requirements upon registry entries (e.g., valid ranges for 224 integers, length limitations on strings, etc.) as well as the 225 exact format in which registry values should be displayed. For 226 numeric assignments, one should specify whether values are to be 227 recorded in decimal, hexadecimal, or some other format. For 228 strings, the encoding format should be specified (ASCII, UTF8, 229 etc.). 231 Initial assignments and reservations 233 Any initial assignments or registrations to be included. In 234 addition, any ranges that are to be reserved for "Private Use", 235 "Reserved", "Unassigned", etc. should be indicated. 237 For example, a document might specify a new registry by including: 239 --------------------------------------------------------------- 241 X. IANA Considerations 243 This document defines a new DHCP option, entitled "FooBar" (see 244 Section y), assigned a value of TBD1 from the DHCP Option space 245 [to be removed upon publication: 246 http://www.iana.org/assignments/bootp-dhcp-parameters] 247 [RFC2132] [RFC2939]: 248 Data 249 Tag Name Length Meaning 250 ---- ---- ------ ------- 251 TBD1 FooBar N FooBar server 253 The FooBar option also defines an 8-bit FooType field, for which 254 IANA is to create and maintain a new sub-registry entitled 255 "FooType values" under the FooBar option. Initial values for the 256 DHCP FooBar FooType registry are given below; future assignments 257 are to be made through Expert Review [BCP26]. 258 Assignments consist of a DHCP FooBar FooType name and its 259 associated value. 261 Value DHCP FooBar FooType Name Definition 262 ---- ------------------------ ---------- 263 0 Reserved 264 1 Frobnitz See Section y.1 265 2 NitzFrob See Section y.2 266 3-254 Unassigned 267 255 Reserved 268 --------------------------------------------------------------- 270 For examples of documents that establish registries, consult 271 [RFC6195], [RFC3575], [RFC3968], and [RFC4520]. 273 2.2. Defining an Appropriate Registry Policy 275 There are several issues to consider when defining the policy for the 276 management of a registry. 278 If the registry's namespace is limited, assignments will need to be 279 made carefully to prevent exhaustion. 281 Even when the space is essentially unlimited, however, it is usually 282 desirable to have at least a minimal review prior to assignment in 283 order to: 285 o prevent the hoarding of or unnecessary wasting of values. For 286 example, if the space consists of text strings, it may be 287 desirable to prevent entities from obtaining large sets of strings 288 that correspond to desirable names (existing company names, for 289 example). 291 o provide a sanity check that the request actually makes sense and 292 is necessary. Experience has shown that some level of minimal 293 review from a subject matter expert is useful to prevent 294 assignments in cases where the request is malformed or not 295 actually needed (for example, an existing assignment for an 296 essentially equivalent service already exists). 298 Perhaps most importantly, unreviewed extensions can impact 299 interoperability and security. See [RFC6709]. 301 When the namespace is essentially unlimited and there are no 302 potential interoperability or security issues, assigned numbers can 303 usually be given out to anyone without any subjective review. In 304 such cases, IANA can make assignments directly, provided that IANA is 305 given detailed instructions on what types of requests it should 306 grant, and it is able to do so without exercising subjective 307 judgement. 309 When this is not the case, some level of review is required. 310 However, it's important to balance adequate review and ease of 311 registration. In many cases, those making registrations will not be 312 IETF participants; requests often come from other standards 313 organizations, from organizations not directly involved in standards, 314 from ad-hoc community work (from an open-source project, for 315 example), and so on. Registration must not be unnecessarily 316 difficult, unnecessarily costly (in terms of time and other 317 resources), nor unnecessarily subject to denial. 319 While it is sometimes necessary to restrict what gets registered 320 (e.g., for limited resources such as bits in a byte, or for items for 321 which unsupported values can be damaging to protocol operation), in 322 many cases having what's in use represented in the registry is more 323 important. Overly strict review criteria and excessive cost (in time 324 and effort) discourage people from even attempting to make a 325 registration. If a registry fails to reflect the protocol elements 326 actually in use, it can adversely affect deployment of protocols on 327 the Internet, and the registry itself is devalued. 329 In particular, when a registry policy that requires involvement of 330 Working Groups, directorates, or other bodies to be actively involved 331 and to support the effort, requests frequently run into concerns that 332 "it's not worth doing a Standards-Track RFC for something this 333 trivial," when, in fact, that requirement was created by the Working 334 Group in the first place, by placing the bar that high. 336 Indeed, publishing any RFC is costly, and a Standards Track RFC is 337 especially so, requiring a great deal of community time for review 338 and discussion, IETF-wide last call, involvement of the entire IESG 339 as well as concentrated time and review from the sponsoring AD, 340 review and action by IANA, and RFC-Editor processing. 342 Therefore, Working Groups and other document developers should use 343 care in selecting appropriate registration policies when their 344 documents create registries. They should select the least strict 345 policy that suits a registry's needs, and look for specific 346 justification for policies that require significant community 347 involvement (Specification Required, in terms of the well-known 348 policies). 350 2.2.1. Using the Well-Known Registration Policies 352 This document defines a number of registration policies in Section 4. 353 Because they benefit from both community experience and wide 354 understanding, their use is encouraged when appropriate. 356 It is also acceptable to cite one of the well-known policies and 357 include additional guidelines for what kind of considerations should 358 be taken into account by the review process. 360 For example, RADIUS [RFC3575] specifies the use of a Designated 361 Expert, but includes specific additional criteria the Designated 362 Expert should follow. 364 The well-known policies from "First Come First Served" to "Standards 365 Action" specify a range of policies in increasing order of 366 strictness: 368 4. First Come First Served 369 No review, minimal documentation. 371 5. Expert Review 372 Expert review, sufficient documentation for review. 374 6. Specification Required 375 Expert review, significant, stable public documentation. 377 7. RFC Required 378 Any RFC publication, IETF or a non-IETF Stream. 380 8. IETF Review 381 RFC publication, IETF Stream only, but need not be Standards 382 Track. 384 9. Standards Action 385 RFC publication, IETF Stream, Standards Track only. 387 Examples of situations that might merit RFC Required, IETF Review, or 388 Standards Action include the following: 390 o When a resource is limited, such as bits in a byte (or in two 391 bytes, or four), or numbers in a limited range. In these cases, 392 allowing registrations that haven't been carefully reviewed and 393 agreed by community consensus could too quickly deplete the 394 allowable values. 396 o When thorough community review is necessary to avoid extending or 397 modifying the protocol in ways that could be damaging. One 398 example is in defining new command codes, as opposed to options 399 that use existing command codes: the former might require a strict 400 policy, where a more relaxed policy could be adequate for the 401 latter. Another example is in defining protocol elements that 402 change the semantics of existing operations. 404 The description in Section 4.10 of "IESG Approval" suggests that the 405 IESG "can (and should) reject a request if another path for 406 registration is available that is more appropriate and there is no 407 compelling reason not to use that path." The IESG should give 408 similar consideration to any registration policy more stringent than 409 Specification Required, asking for justification and ensuring that 410 more relaxed policies have been considered, and the strict policy is 411 the right one. 413 Accordingly, document developers need to anticipate this and document 414 their considerations for selecting the specified policy (ideally, in 415 the document itself; failing that, in the shepherd writeup). 416 Likewise, the document shepherd should ensure that the selected 417 policies have been justified before sending the document to the IESG. 419 When specifications are revised, registration policies should be 420 reviewed in light of experience since the policies were set. 422 Note that the well-known policies are not exclusive; there are 423 situations where a different policy might be more appropriate. 425 2.2.2. Using Multiple Policies in Combination 427 In some situations, it is necessary to define multiple registration 428 policies. For example, registrations through the normal IETF process 429 might use one policy, while registrations from outside the process 430 would have a different policy applied. 432 Thus, a particular registry might want to use a policy such as "RFC 433 Required" or "IETF Review" sometimes, with a designated expert 434 checking a "Specification Required" policy at other times. 436 The alternative to using a combination requires either that all 437 requests come through RFCs or that requests in RFCs go through review 438 by the designated expert, even though they already have IETF review 439 and consensus. 441 This can be documented in the IANA Considerations section when the 442 registry is created: 444 IANA is asked to create the registry "Fruit Access Flags" as a 445 sub-registry of "Fruit Parameters". New registrations will be 446 permitted through either the IETF Review policy or the 447 Specification Required policy [BCP26]. 449 Such combinations will commonly use one of {Standards Action, IETF 450 Review, RFC Required} in combination with one of {Specification 451 Required, Expert Review}. 453 2.3. Revising Existing Registries 455 Updating the registration process for an already existing (previously 456 created) namespace (whether created explicitly or implicitly) follows 457 a process similar to that used when creating a new namespace. That 458 is, a document is produced that makes reference to the existing 459 namespace and then provides detailed guidelines for handling 460 assignments in each individual namespace. Such documents are 461 normally processed as Best Current Practices (BCPs) [RFC2026]. 463 Example documents that updated the guidelines for managing (then) 464 pre-existing registries include: [RFC6195], [RFC3228], and [RFC3575]. 466 3. Registering New Values in an Existing Registry 468 3.1. Documentation Requirements for Registrations 470 Often, documents request an assignment from an already existing 471 namespace (one created by a previously published document). 473 Such documents should clearly identify the namespace in which each 474 value is to be registered. If the registration goes into a sub- 475 registry, the author should clearly describe where the assignment or 476 registration should go. Use the exact namespace name as listed on 477 the IANA web page, and cite the RFC where the namespace is defined. 479 There is no need to mention what the assignment policy for new 480 assignments is, as that should be clear from the references. 482 When referring to an existing registry, providing a URL to precisely 483 identify the registry is helpful. Such URLs, however, should usually 484 be removed from the RFC prior to final publication, since IANA URLs 485 are not guaranteed to be stable in the future. In cases where it is 486 important to include a URL in the document, IANA should concur on its 487 inclusion. 489 For example, a document could contain something like this: 491 [TO BE REMOVED: This registration should be made in the Foobar 492 Operational Parameters registry, located at http://www.iana.org/ 493 assignments/foobar-registry] 495 Each value requested should be given a unique reference. When the 496 value is numeric, use the notation: TBD1, TBD2, etc. Throughout the 497 document where an actual IANA-assigned value should be filled in, use 498 the "TBDx" notation. This helps ensure that the final RFC has the 499 correct assigned values inserted in all of the relevant places where 500 the value is expected to appear in the final document. For values 501 that are text strings, a specific name can be suggested. IANA will 502 normally assign the name, unless it conflicts with a name already in 503 use. 505 Normally, the values to be used are chosen by IANA and documents 506 should specify values of "TBD". However, in some cases, a value may 507 have been used for testing or in early implementations. In such 508 cases, it is acceptable to include text suggesting what specific 509 value should be used (together with the reason for the choice). For 510 example, one might include the text "the value XXX is suggested as it 511 is used in implementations". However, it should be noted that 512 suggested values are just that; IANA will attempt to assign them, but 513 may find that impossible, if the proposed number has already been 514 assigned for some other use. 516 For some registries, IANA has a long-standing policy prohibiting 517 assignment of names or codes on a vanity or organization-name basis. 518 For example, codes are always assigned sequentially unless there is a 519 strong reason for making an exception. Nothing in this document is 520 intended to change those policies or prevent their future 521 application. 523 The IANA Considerations section should summarize all of the IANA 524 actions, with pointers to the relevant sections elsewhere in the 525 document as appropriate. When multiple values are requested, it is 526 generally helpful to include a summary table. It is also helpful for 527 this table to be in the same format as it appears or will appear on 528 the IANA web site. For example: 530 Value Description Reference 531 -------- ------------------- --------- 532 TBD1 Foobar [[this RFC]] 534 Note: In cases where authors feel that including the full table is 535 too verbose or repetitive, authors should still include the table in 536 the draft, but may include a note asking that the table be removed 537 prior to publication of the final RFC. 539 As an example, the following text could be used to request assignment 540 of a DHCPv6 option number: 542 IANA has assigned an option code value of TBD1 to the DNS 543 Recursive Name Server option and an option code value of TBD2 to 544 the Domain Search List option from the DHCP option code space 545 defined in Section 24.3 of RFC 3315. 547 3.2. Updating Existing Registrations 549 Even after a number has been assigned, some types of registrations 550 contain additional information that may need to be updated over time. 552 For example, MIME media types, character sets, and language tags 553 typically include more information than just the registered value 554 itself, and may need things such as point-of-contact information, 555 security issues, pointers to updates, or literature references 556 updated. 558 In such cases, the document defining the namespace must clearly state 559 who is responsible for maintaining and updating a registration. 560 Depending on the registry, it may be appropriate to specify one or 561 more of: 563 o Letting registrants and/or nominated change controllers update 564 their own registrations, subject to the same constraints and 565 review as with new registrations. 567 o Allowing attachment of comments to the registration. This can be 568 useful in cases where others have significant objections to a 569 registration, but the author does not agree to change the 570 registration. 572 o Designating the IESG, a designated expert, or another entity as 573 having the right to change the registrant associated with a 574 registration and any requirements or conditions on doing so. This 575 is mainly to get around the problem when a registrant cannot be 576 reached in order to make necessary updates. 578 3.3. Overriding Registration Procedures 580 Experience has shown that the documented IANA considerations for 581 individual protocols do not always adequately cover the reality of 582 registry operation, or are not sufficiently clear. In addition, 583 documented IANA considerations are sometimes found to be too 584 stringent to allow even working group documents (for which there is 585 strong consensus) to perform a registration in advance of actual RFC 586 publication. 588 In order to allow assignments in such cases, the IESG is granted 589 authority to override registration procedures and approve assignments 590 on a case-by-case basis. 592 The intention here is not to overrule properly documented procedures, 593 or to obviate the need for protocols to properly document their IANA 594 considerations. Rather, it is to permit assignments in specific 595 cases where it is obvious that the assignment should just be made, 596 but updating the IANA process beforehand is too onerous. 598 When the IESG is required to take action as described in this 599 section, it is a strong indicator that the applicable registration 600 procedures should be updated, possibly in parallel with the work that 601 instigated it. 603 4. Well-Known Registration Policies 605 The following are some defined policies, most of which are in use 606 today. These cover a range of typical policies that have been used 607 to describe the procedure for assigning new values in a namespace. 608 It is not strictly required that documents use these terms; the 609 actual requirement is that the instructions to IANA be clear and 610 unambiguous. However, use of these terms is strongly RECOMMENDED, 611 because their meanings are widely understood. The terms are fully 612 explained in the following subsections. 614 1. Private Use 615 2. Experimental Use 616 3. Hierarchical Allocation 617 4. First Come First Served 618 5. Expert Review 619 6. Specification Required 620 7. RFC Required 621 8. IETF Review 622 9. Standards Action 623 10. IESG Approval 625 It should be noted that it often makes sense to partition a namespace 626 into multiple categories, with assignments within each category 627 handled differently. Many protocols now partition namespaces into 628 two or more parts, with one range reserved for Private or 629 Experimental Use while other ranges are reserved for globally unique 630 assignments assigned following some review process. Dividing a 631 namespace into ranges makes it possible to have different policies in 632 place for different ranges and different use cases. 634 Similarly, it will often be useful to specify multiple policies in 635 parallel, with each policy being used under different circumstances. 636 For more discussion of that topic, see Section 2.2.2. 638 Examples: 640 LDAP [RFC4520] 641 TLS ClientCertificateType Identifiers [RFC5246] (as detailed in 642 the subsections below) 643 Pseudowire Edge to Edge Emulation (PWE3) [RFC4446] 645 4.1. Private Use 646 For private or local use only, with the type and purpose defined by 647 the local site. No attempt is made to prevent multiple sites from 648 using the same value in different (and incompatible) ways. There is 649 no need for IANA to review such assignments (since IANA does not 650 record them) and assignments are not generally useful for broad 651 interoperability. It is the responsibility of the sites making use 652 of the Private Use range to ensure that no conflicts occur (within 653 the intended scope of use). 655 Examples: 657 Site-specific options in DHCP [RFC2939] 658 Fibre Channel Port Type Registry [RFC4044] 659 TLS ClientCertificateType Identifiers 224-255 [RFC5246] 661 4.2. Experimental Use 663 Similar to private or local use only, with the purpose being to 664 facilitate experimentation. See [RFC3692] for details. 666 Example: 668 Experimental Values in IPv4, IPv6, ICMPv4, ICMPv6, UDP, and TCP 669 Headers [RFC4727] 671 4.3. Hierarchical Allocation 673 Delegated managers can assign values provided they have been given 674 control over that part of the namespace. IANA controls the higher 675 levels of the namespace according to one of the other policies. 677 Examples: 679 DNS names 680 Object Identifiers 681 IP addresses 683 4.4. First Come First Served 685 Assignments are made to anyone on a first come, first served basis. 686 There is no substantive review of the request, other than to ensure 687 that it is well-formed and doesn't duplicate an existing assignment. 688 However, requests must include a minimal amount of clerical 689 information, such as a point of contact (including an email address) 690 and a brief description of how the value will be used. Additional 691 information specific to the type of value requested may also need to 692 be provided, as defined by the namespace. For numbers, the exact 693 value is generally assigned by IANA; with names, specific text 694 strings can usually be requested. 696 Examples: 698 SASL mechanism names [RFC4422] 699 LDAP Protocol Mechanisms and LDAP Syntax [RFC4520] 701 4.5. Expert Review 703 (Sometimes also called "Designated Expert" in earlier editions of 704 this document.) Review and approval by a designated expert is 705 required. The required documentation and review criteria for use by 706 the designated expert should be provided when defining the registry. 707 For example, see Sections 6 and 7.2 in [RFC3748]. 709 It is particularly important, when using a designated expert, to give 710 clear guidance to the expert, laying out criteria for performing an 711 evaluation and reasons for rejecting a request. When specifying a 712 policy that involves a designated expert, the IANA Considerations 713 SHOULD contain such guidance. It is also a good idea to include, 714 when possible, a sense of whether many registrations are expected 715 over time, or if the registry is expected to be updated infrequently 716 or in exceptional circumstances only. 718 Examples: 720 EAP Method Types [RFC3748] 721 HTTP Digest AKA algorithm versions [RFC4169] 722 URI schemes [RFC4395] 723 GEOPRIV Location Types [RFC4589] 725 4.6. Specification Required 727 Review and approval by a Designated Expert is required, (as in 728 Section 4.5) and the values and their meanings must be documented in 729 a permanent and readily available public specification, in sufficient 730 detail so that interoperability between independent implementations 731 is possible. The Designated Expert will review the public 732 specification and evaluate whether it is sufficiently clear to allow 733 interoperable implementations. The intention behind "permanent and 734 readily available" is that a document can reasonably be expected to 735 be findable and retrievable long after IANA assignment of the 736 requested value. Publication of an RFC is an ideal means of 737 achieving this requirement, but Specification Required is intended to 738 also cover the case of a document published outside of the RFC path. 739 For RFC publication, the normal RFC review process is expected to 740 provide the necessary review for interoperability, though the 741 designated expert may be a particularly well-qualified person to 742 perform such a review. 744 When specifying this policy, just use the term "Specification 745 Required". Some specifications have chosen to refer to it as "Expert 746 Review with Specification Required", and that only causes confusion. 748 Examples: 750 Diffserv-aware TE Bandwidth Constraints Model Identifiers 751 [RFC4124] 752 TLS ClientCertificateType Identifiers 64-223 [RFC5246] 753 ROHC Profile Identifiers [RFC5795] 755 4.7. RFC Required 757 RFC publication suffices, as an IETF submission or in any other 758 stream (currently an RFC Editor Independent Submission [RFC5742] or 759 an RFC in the IRTF or IAB Stream). Unless otherwise specified, any 760 type of RFC is sufficient (currently Standards Track, BCP, 761 Informational, Experimental, Historic). 763 4.8. IETF Review 765 (Formerly called "IETF Consensus" in the first edition of this 766 document.) New values are assigned only through RFCs in the IETF 767 Stream -- those that have been shepherded through the IESG as AD- 768 Sponsored or IETF working group Documents [RFC2026] [RFC5378]. The 769 intention is that the document and proposed assignment will be 770 reviewed by the IESG and appropriate IETF working groups (or experts, 771 if suitable working groups no longer exist) to ensure that the 772 proposed assignment will not negatively impact interoperability or 773 otherwise extend IETF protocols in an inappropriate or damaging 774 manner. 776 To ensure adequate community review, such documents are shepherded 777 through the IESG as AD-sponsored or working group documents with an 778 IETF Last Call. 780 Examples: 782 IPSECKEY Algorithm Types [RFC4025] 783 Accounting-Auth-Method AVP values in DIAMETER [RFC4005] 784 TLS Extension Types [RFC5246] 786 4.9. Standards Action 788 Values are assigned only for Standards Track RFCs approved by the 789 IESG. 791 Examples: 793 BGP message types [RFC4271] 794 Mobile Node Identifier option types [RFC4283] 795 TLS ClientCertificateType Identifiers 0-63 [RFC5246] 796 DCCP Packet Types [RFC4340] 798 4.10. IESG Approval 800 New assignments may be approved by the IESG. Although there is no 801 requirement that the request be documented in an RFC, the IESG has 802 discretion to request documents or other supporting materials on a 803 case-by-case basis. 805 IESG Approval is not intended to be used often or as a "common case"; 806 indeed, it has seldom been used in practice during the period RFC 807 2434 was in effect. Rather, it is intended to be available in 808 conjunction with other policies as a fall-back mechanism in the case 809 where one of the other allowable approval mechanisms cannot be 810 employed in a timely fashion or for some other compelling reason. 811 IESG Approval is not intended to circumvent the public review 812 processes implied by other policies that could have been employed for 813 a particular assignment. IESG Approval would be appropriate, 814 however, in cases where expediency is desired and there is strong 815 consensus (such as from a working group) for making the assignment. 817 The following guidelines are suggested for any evaluation under IESG 818 Approval: 820 o The IESG can (and should) reject a request if another path for 821 registration is available that is more appropriate and there is no 822 compelling reason not to use that path. 824 o Before approving a request, the community should be consulted, via 825 a "call for comments" that provides as much information as is 826 reasonably possible about the request. 828 Examples: 830 IPv4 Multicast address assignments [RFC5771] 831 IPv4 IGMP Type and Code values [RFC3228] 832 Mobile IPv6 Mobility Header Type and Option values [RFC6275] 834 5. Designated Experts 836 5.1. The Motivation for Designated Experts 838 IANA does not define registry policy itself; rather, it carries out 839 policies that have been defined by others and published in RFCs. As 840 part of that process, review of proposed registrations is often 841 appropriate. 843 A common way to ensure such review is for a proposed registration to 844 be published as an RFC, as this ensures that the specification is 845 publicly and permanently available. It is particularly important if 846 any potential interoperability issues might arise. For example, some 847 assignments are not just assignments, but also involve an element of 848 protocol specification. A new option may define fields that need to 849 be parsed and acted on, which (if specified poorly) may not fit 850 cleanly with the architecture of other options or the base protocols 851 on which they are built. 853 In some cases, however, the burden of publishing an RFC in order to 854 register a protocol element is excessive. 856 However, it is generally still useful (and sometimes necessary) to 857 discuss proposed registrations within the community, on a mailing 858 list. Such a mailing list provides opportunity for public review 859 prior to assignment, and allows for a consultative process when 860 registrants want help in understanding what a proper registration 861 should contain. 863 While discussion on a mailing list can provide valuable technical 864 feedback, opinions may vary and discussions may continue for some 865 time without clear resolution. In addition, IANA cannot participate 866 in all of these mailing lists and cannot determine if or when such 867 discussions reach consensus. Therefore, IANA relies on a "designated 868 expert" for advice regarding the specific question of whether an 869 assignment should be made. The designated expert is an individual 870 who is responsible for carrying out an appropriate evaluation and 871 returning a recommendation to IANA. 873 It should be noted that a key motivation for having designated 874 experts is for the IETF to provide IANA with a subject matter expert 875 to whom the evaluation process can be delegated. IANA forwards 876 requests for an assignment to the expert for evaluation, and the 877 expert (after performing the evaluation) informs IANA as to whether 878 or not to make the assignment or registration. 880 It will often be useful to use a designated expert only some of the 881 time, as a supplement to other processes. For more discussion of 882 that topic, see Section 2.2.2. 884 5.2. The Role of the Designated Expert 886 The designated expert is responsible for initiating and coordinating 887 the appropriate review of an assignment request. The review may be 888 wide or narrow, depending on the situation and the judgment of the 889 designated expert. This may involve consultation with a set of 890 technology experts, discussion on a public mailing list, consultation 891 with a working group (or its mailing list if the working group has 892 disbanded), etc. Ideally, the designated expert follows specific 893 review criteria as documented with the protocol that creates or uses 894 the namespace. See the IANA Considerations sections of [RFC3748] and 895 [RFC3575] for specific examples. 897 Designated experts are expected to be able to defend their decisions 898 to the IETF community, and the evaluation process is not intended to 899 be secretive or bestow unquestioned power on the expert. Experts are 900 expected to apply applicable documented review or vetting procedures, 901 or in the absence of documented criteria, follow generally accepted 902 norms such as those in Section 5.3. 904 Section 3.2 discusses disputes and appeals in more detail. 906 Designated experts are appointed by the IESG (normally upon 907 recommendation by the relevant Area Director). They are typically 908 named at the time a document creating or updating a namespace is 909 approved by the IESG, but as experts originally appointed may later 910 become unavailable, the IESG will appoint replacements if necessary. 912 For some registries, it has proven useful to have multiple designated 913 experts. Sometimes those experts work together in evaluating a 914 request, while in other cases additional experts serve as backups. 915 In cases of disagreement among those experts, it is the 916 responsibility of those experts to make a single clear recommendation 917 to IANA. It is not appropriate for IANA to resolve disputes among 918 experts. In extreme situations, such as deadlock, the IESG may need 919 to step in to resolve the problem. 921 In registries where a pool of experts evaluates requests, the pool 922 should have a single chair responsible for defining how requests are 923 to be assigned to and reviewed by experts. In some cases, the expert 924 pool may consist of a primary and backups, with the backups involved 925 only when the primary expert is unavailable. In other cases, IANA 926 might assign requests to individual members in sequential or 927 approximate random order. In the event that IANA finds itself having 928 received conflicting advice from its experts, it is the 929 responsibility of the pool's chair to resolve the issue and provide 930 IANA with clear instructions. 932 Since the designated experts are appointed by the IESG, they may be 933 removed by the IESG. 935 5.3. Designated Expert Reviews 937 In the years since RFC 2434 was published and has been put to use, 938 experience has led to the following observations: 940 o A designated expert must respond in a timely fashion, normally 941 within a week for simple requests to a few weeks for more complex 942 ones. Unreasonable delays can cause significant problems for 943 those needing assignments, such as when products need code points 944 to ship. This is not to say that all reviews can be completed 945 under a firm deadline, but they must be started, and the requester 946 and IANA should have some transparency into the process if an 947 answer cannot be given quickly. 949 o If a designated expert does not respond to IANA's requests within 950 a reasonable period of time, either with a response or with a 951 reasonable explanation for the delay (some requests may be 952 particularly complex), and if this is a recurring event, IANA must 953 raise the issue with the IESG. Because of the problems caused by 954 delayed evaluations and assignments, the IESG should take 955 appropriate actions to ensure that the expert understands and 956 accepts his or her responsibilities, or appoint a new expert. 958 o The designated expert is not required to personally bear the 959 burden of evaluating and deciding all requests, but acts as a 960 shepherd for the request, enlisting the help of others as 961 appropriate. In the case that a request is denied, and rejecting 962 the request is likely to be controversial, the expert should have 963 the support of other subject matter experts. That is, the expert 964 must be able to defend a decision to the community as a whole. 966 When a designated expert is used, the documentation should give clear 967 guidance to the designated expert, laying out criteria for performing 968 an evaluation and reasons for rejecting a request. In the case where 969 there are no specific documented criteria, the presumption should be 970 that a code point should be granted unless there is a compelling 971 reason to the contrary. Possible reasons to deny a request include 972 these: 974 o Scarcity of code points, where the finite remaining code points 975 should be prudently managed, or when a request for a large number 976 of code points is made, when a single code point is the norm. 978 o Documentation is not of sufficient clarity to evaluate or ensure 979 interoperability. 981 o The code point is needed for a protocol extension, but the 982 extension is not consistent with the documented (or generally 983 understood) architecture of the base protocol being extended, and 984 would be harmful to the protocol if widely deployed. It is not 985 the intent that "inconsistencies" refer to minor differences "of a 986 personal preference nature". Instead, they refer to significant 987 differences such as inconsistencies with the underlying security 988 model, implying a change to the semantics of an existing message 989 type or operation, requiring unwarranted changes in deployed 990 systems (compared with alternate ways of achieving a similar 991 result), etc. 993 o The extension would cause problems with existing deployed systems. 995 o The extension would conflict with one under active development by 996 the IETF, and having both would harm rather than foster 997 interoperability. 999 When a designated expert is used, documents MUST NOT name the 1000 designated expert in the document itself; instead, any suggested 1001 names should be relayed to the appropriate Area Director at the time 1002 the document is sent to the IESG for approval. This is usually done 1003 in the document shepherd writeup. 1005 If the request should also be reviewed on a specific public mailing 1006 list, its address should be specified. 1008 5.4. Expert Reviews and the Document Lifecycle 1010 Review by the designated expert is necessarily done at a particular 1011 point in time, and represents review of a particular version of the 1012 document. Deciding when the review should take place is a question 1013 of good judgment. And while re-reviews might be done when it's 1014 acknowledged that the documentation of the registered item has 1015 changed substantially, making sure that re-review happens requires 1016 attention and care. 1018 It is possible, through carelessness, accident, inattentiveness, or 1019 even willful disregard, that changes might be made after the 1020 designated expert's review and approval that would, if the document 1021 were re-reviewed, cause the expert not to approve the registration. 1022 It is up to the IESG, with the token held by the responsible Area 1023 Director, to be alert to such situations and to recognize that such 1024 changes need to be checked. 1026 6. Well-Known Registration Status Terminology 1028 The following labels describe the status of an individual (or range) 1029 of assignments: 1031 Private Use: Private use only (not assigned), as described in 1032 Section 4.1. 1034 Experimental: Available for general experimental use as described 1035 in [RFC3692]. IANA does not record specific assignments for 1036 any particular use. 1038 Unassigned: Not currently assigned, and available for assignment 1039 via documented procedures. While it's generally clear that 1040 any values that are not registered are unassigned and 1041 available for assignment, it is sometimes useful to 1042 explicitly specify that situation. Note that this is 1043 distinctly different from "Reserved". 1045 Reserved: Not assigned and not available for assignment. Reserved 1046 values are held for special uses, such as to extend the 1047 namespace when it becomes exhausted. Note that this is 1048 distinctly different from "Unassigned". 1050 7. Documentation References in IANA Registries 1052 Usually, registries and registry entries include references to 1053 documentation (RFCs or other documents). The purpose of these 1054 references is to provide pointers for implementors to find details 1055 necessary for implementation, NOT to simply note what document 1056 created the registry or entry. Therefore: 1058 o If a document registers an item that is defined and explained 1059 elsewhere, the registered reference should be to that document, 1060 and not to the document that is merely performing the 1061 registration. 1063 o If the registered item is defined and explained in the current 1064 document, it is important to include sufficient information to 1065 enable implementors to understand the item and to create a proper 1066 implementation. 1068 o If the registered item is explained primarily in a specific 1069 section of the reference document, it is useful to include a 1070 section reference. For example, "[RFC9876], Section 3.2", rather 1071 than just "[RFC9876]". 1073 o For documentation of a new registry, the reference should provide 1074 information about the registry itself, not just a pointer to the 1075 creation of it. Useful information includes the purpose of the 1076 registry, a rationale for its creation, documentation of the 1077 process and policy for new registrations, guidelines for new 1078 registrants or designated experts, and other such related 1079 information. 1081 8. What to Do in "bis" Documents 1083 On occaison, an RFC is issued that obsoletes a previous edition of 1084 the same document. We sometimes call these "bis" documents, such as 1085 when RFC 9876 is updated by draft-ietf-foo-rfc9876bis. When the 1086 original document created registries and/or registered entries, there 1087 is a question of how to handle the IANA Considerations section in the 1088 "bis" document. 1090 If the registrations specify the original document as a reference, 1091 those registrations should be updated to point to the current (not 1092 obsolete) documentation for those items. Usually, that will mean 1093 changing the reference to be the "bis" document. 1095 For example, suppose RFC 9876 registered the "BANANA" flag in the 1096 "Fruit Access Flags" registry, and the documentation for that flag is 1097 in Section 3.2. 1099 The current registry might look, in part, like this: 1101 Name Description Reference 1102 -------- ------------------- --------- 1103 BANANA Flag for bananas [RFC9876], Section 3.2 1105 If draft-ietf-foo-rfc9876bis obsoletes RFC 9876 and, because of some 1106 rearrangement, now documents the flag in Section 4.1.2, the IANA 1107 Considerations of the bis document might contain text such as this: 1109 IANA is asked to change the registration information for the 1110 BANANA flag in the "Fruit Access Flags" registry to the following: 1112 Name Description Reference 1113 -------- ------------------- --------- 1114 BANANA Flag for bananas [[this RFC]], Section 4.2.1 1116 In many cases, if there are a number of registered references to the 1117 original RFC and the document organization has not changed the 1118 registered section numbering much, it may simply be reasonable to do 1119 this: 1121 Because this document obsoletes RFC 9876, IANA is asked to change 1122 all registration information that references [RFC9876] to instead 1123 reference [[this RFC]]. 1125 If information for registered items has been or is being moved to 1126 other documents, then, of course, the registration information should 1127 be changed to point to those other documents. In no case is it 1128 reasonable to leave documentation pointers to the obsoleted document 1129 for any registries or registered items that are still in current use. 1131 9. Miscellaneous Issues 1133 9.1. When There Are No IANA Actions 1134 Before an Internet-Draft can be published as an RFC, IANA needs to 1135 know what actions (if any) it needs to perform. Experience has shown 1136 that it is not always immediately obvious whether a document has no 1137 IANA actions, without reviewing the document in some detail. In 1138 order to make it clear to IANA that it has no actions to perform (and 1139 that the author has consciously made such a determination), such 1140 documents should include an IANA Considerations section that states: 1142 This document has no IANA actions. 1144 This statement, or an equivalent, must only be inserted after the 1145 working group or individual submitter has carefully verified it to be 1146 true. Using such wording as a matter of "boilerplate" or without 1147 careful consideration can lead to incomplete or incorrect IANA 1148 actions being performed. 1150 If a specification makes use of values from a namespace that is not 1151 managed by IANA, it may be useful to note this fact, with wording 1152 such as this: 1154 The values of the Foobar parameter are assigned by the Barfoo 1155 registry on behalf of the Rabfoo Forum. Therefore, this document 1156 has no IANA actions. 1158 In some cases, the absence of IANA-assigned values may be considered 1159 valuable information for future readers; in other cases, it may be 1160 considered of no value once the document has been approved, and may 1161 be removed before archival publication. This choice should be made 1162 clear in the draft, for example, by including a sentence such as 1164 [RFC Editor: please remove this section prior to publication.] 1166 or 1168 [RFC Editor: please do not remove this section.] 1170 9.2. Namespaces Lacking Documented Guidance 1172 For all existing RFCs that either explicitly or implicitly rely on 1173 IANA to evaluate assignments without specifying a precise evaluation 1174 policy, IANA (in consultation with the IESG) will continue to decide 1175 what policy is appropriate. Changes to existing policies can always 1176 be initiated through the normal IETF consensus process. 1178 All future RFCs that either explicitly or implicitly rely on IANA to 1179 register or otherwise manage namespace assignments MUST provide 1180 guidelines for managing the namespace. 1182 9.3. After-the-Fact Registrations 1183 Occasionally, IANA becomes aware that an unassigned value from a 1184 managed namespace is in use on the Internet or that an assigned value 1185 is being used for a different purpose than originally registered. 1186 IANA will not condone such misuse; procedures of the type described 1187 in this document MUST be applied to such cases. In the absence of 1188 specifications to the contrary, values may only be reassigned for a 1189 different purpose with the consent of the original assignee (when 1190 possible) and with due consideration of the impact of such a 1191 reassignment. In cases of likely controversy, consultation with the 1192 IESG is advised. 1194 9.4. Reclaiming Assigned Values 1196 Reclaiming previously assigned values for reuse is tricky, because 1197 doing so can lead to interoperability problems with deployed systems 1198 still using the assigned values. Moreover, it can be extremely 1199 difficult to determine the extent of deployment of systems making use 1200 of a particular value. However, in cases where the namespace is 1201 running out of unassigned values and additional ones are needed, it 1202 may be desirable to attempt to reclaim unused values. When 1203 reclaiming unused values, the following (at a minimum) should be 1204 considered: 1206 o Attempts should be made to contact the original party to which a 1207 value is assigned, to determine if the value was ever used, and if 1208 so, the extent of deployment. (In some cases, products were never 1209 shipped or have long ceased being used. In other cases, it may be 1210 known that a value was never actually used at all.) 1212 o Reassignments should not normally be made without the concurrence 1213 of the original requester. Reclamation under such conditions 1214 should only take place where there is strong evidence that a value 1215 is not widely used, and the need to reclaim the value outweighs 1216 the cost of a hostile reclamation. In any case, IESG Approval is 1217 needed in this case. 1219 o It may be appropriate to write up the proposed action and solicit 1220 comments from relevant user communities. In some cases, it may be 1221 appropriate to write an RFC that goes through a formal IETF 1222 process (including IETF Last Call) as was done when DHCP reclaimed 1223 some of its "Private Use" options [RFC3942]. 1225 9.5. Contact Person vs Assignee or Owner 1227 Many registries include designation of a technical or administrative 1228 contact associated with each entry. Often, this is recorded as 1229 contact information for an individual. It is unclear, though, what 1230 role the individual has with respect to the registration: is this 1231 item registered on behalf of the individual, the company the 1232 individual worked for, or perhaps another organization the individual 1233 was acting for? 1234 This matters because some time later, when the individual has changed 1235 jobs or roles, and perhaps can no longer be contacted, someone might 1236 want to update the registration. IANA has no way to know what 1237 company, organization, or individual should be allowed to take the 1238 registration over. For registrations rooted in RFCs, the stream 1239 owner (such as the IESG or the IAB) can make an overriding decision. 1240 But in other cases, there is no recourse. 1242 Registries can include, in addition to a "Contact" field, an 1243 "Assignee" or "Owner" field that can be used to address this 1244 situation, giving IANA clear guidance as to the actual owner of the 1245 registration. Alternatively, organizations can put an organizational 1246 role into the "Contact" field in order to make their ownership clear. 1248 9.6. Closing or Obsoleting a Registry 1250 [[This section needs to be resolved before publication.]] 1252 9.7. BCP 78/79 Issues in Registries 1254 [[This section needs to be resolved before publication, but I'm not 1255 sure anything's needed here after all. ]] 1257 10. Appeals 1259 Appeals of registration decisions made by IANA can be made using the 1260 normal IETF appeals process as described in Section 6.5 of [RFC2026]. 1261 Specifically, appeals should be directed to the IESG, followed (if 1262 necessary) by an appeal to the IAB, etc. 1264 11. Mailing Lists 1266 All IETF mailing lists associated with evaluating or discussing 1267 assignment requests as described in this document are subject to 1268 whatever rules of conduct and methods of list management are 1269 currently defined by Best Current Practices or by IESG decision. 1271 12. Security Considerations 1273 Information that creates or updates a registration needs to be 1274 authenticated and authorized. IANA updates registries according to 1275 instructions in published RFCs and from the IESG. It also may accept 1276 clarifications from document authors, relevant working group chairs, 1277 Designated Experts, and mail list participants, too. 1279 Information concerning possible security vulnerabilities of a 1280 protocol may change over time. Likewise, security vulnerabilities 1281 related to how an assigned number is used may change as well. As new 1282 vulnerabilities are discovered, information about such 1283 vulnerabilities may need to be attached to existing registrations, so 1284 that users are not misled as to the true security issues surrounding 1285 the use of a registered number. 1287 An analysis of security issues is generally required for all 1288 protocols that make use of parameters (data types, operation codes, 1289 keywords, etc.) used in IETF protocols or registered by IANA. Such 1290 security considerations are usually included in the protocol document 1291 [RFC3552]. It is the responsibility of the IANA considerations 1292 associated with a particular registry to specify what (if any) 1293 security considerations must be provided when assigning new values, 1294 and the process for reviewing such claims. 1296 13. To-Do List; resolve and remove before requesting publication 1298 Just was speaking with someone at the IANA office hours. I was 1299 looking through the 5226bis draft and there is nothing in there about 1300 how to deprecate values in registries. Might be something good to 1301 add. 1303 14. Changes Relative to Earlier Editions of BCP 26 1305 14.1. 2013: Changes in This Document Relative to RFC 5226 1307 Significant additions: 1309 o Added Section 5.4, Expert Reviews and the Document Lifecycle 1311 o Moved well-known policies into a separate section for each, 1312 subsections of Section 4. 1314 o Added Section 2.2, Best Practice for Selecting an Appropriate 1315 Policy. 1317 o Added Section 2.2.2, Using Multiple Policies in Combination. 1319 o Added Section 7, Documentation References in IANA Registries 1321 o Added Section 8, What to Do in "bis" Documents 1323 o Added Section 9.5, Contact Person vs Assignee or Owner 1325 o Added Section 9.6, Closing or Obsoleting a Registry 1327 o Added Section 9.7, BCP 78/79 Issues in Registries 1329 Clarifications and such: 1331 o Some reorganization -- moved text around for clarity and easier 1332 reading. 1334 o Made clarifications about identification of IANA registries and 1335 use of URLs for them. 1337 o Clarified the distinction between "Unassigned" and "Reserved". 1339 o Made some clarifications in "Expert Review" about instructions to 1340 the designated expert. 1342 o Made some clarifications in "Specification Required" about how to 1343 declare this policy. 1345 o Assorted minor clarifications and editorial changes throughout. 1347 14.2. 2008: Changes in RFC 5226 Relative to RFC 2434 1349 Changes include: 1351 o Major reordering of text to expand descriptions and to better 1352 group topics such as "updating registries" vs. "creating new 1353 registries", in order to make it easier for authors to find the 1354 text most applicable to their needs. 1356 o Numerous editorial changes to improve readability. 1358 o Changed the term "IETF Consensus" to "IETF Review" and added more 1359 clarifications. History has shown that people see the words "IETF 1360 Consensus" (without consulting the actual definition) and are 1361 quick to make incorrect assumptions about what the term means in 1362 the context of IANA Considerations. 1364 o Added "RFC Required" to list of defined policies. 1366 o Much more explicit directions and examples of "what to put in 1367 RFCs". 1369 o "Specification Required" now implies use of a Designated Expert to 1370 evaluate specs for sufficient clarity. 1372 o Significantly changed the wording in the Designated Experts 1373 section. Main purpose is to make clear that Expert Reviewers are 1374 accountable to the community, and to provide some guidance for 1375 review criteria in the default case. 1377 o Changed wording to remove any special appeals path. The normal 1378 RFC 2026 appeals path is used. 1380 o Added a section about reclaiming unused value. 1382 o Added a section on after-the-fact registrations. 1384 o Added a section indicating that mailing lists used to evaluate 1385 possible assignments (such as by a Designated Expert) are subject 1386 to normal IETF rules. 1388 15. Acknowledgments 1390 15.1. Acknowledgments for This Document (2013) 1391 Thomas Narten and Harald Tveit Alvestrand edited the two earlier 1392 editions of this document (RFCs 2434 and 5226), and Thomas continues 1393 his role in this third edition. Much of the text from RFC 5226 1394 remains in this edition. 1396 Special thanks to Mark Nottingham for thoroughly reviewing the 1397 document and reorganizing the text for better organization and 1398 readability. 1400 15.2. Acknowledgments from the second edition (2008) 1402 The original acknowledgments section in RFC 5226 was: 1404 This document has benefited from specific feedback from Jari Arkko, 1405 Marcelo Bagnulo Braun, Brian Carpenter, Michelle Cotton, Spencer 1406 Dawkins, Barbara Denny, Miguel Garcia, Paul Hoffman, Russ Housley, 1407 John Klensin, Allison Mankin, Blake Ramsdell, Mark Townsley, Magnus 1408 Westerlund, and Bert Wijnen. 1410 15.3. Acknowledgments from the first edition (1998) 1412 The original acknowledgments section in RFC 2434 was: 1414 Jon Postel and Joyce Reynolds provided a detailed explanation on what 1415 IANA needs in order to manage assignments efficiently, and patiently 1416 provided comments on multiple versions of this document. Brian 1417 Carpenter provided helpful comments on earlier versions of the 1418 document. One paragraph in the Security Considerations section was 1419 borrowed from [RFC4288]. 1421 16. References 1423 16.1. Normative References 1425 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 1426 Requirement Levels", BCP 14, RFC 2119, March 1997. 1428 16.2. Informative References 1430 [RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791, September 1431 1981. 1433 [RFC2026] Bradner, S., "The Internet Standards Process -- Revision 1434 3", BCP 9, RFC 2026, October 1996. 1436 [RFC2132] Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor 1437 Extensions", RFC 2132, March 1997. 1439 [RFC2860] Carpenter, B., Baker, F. and M. Roberts, "Memorandum of 1440 Understanding Concerning the Technical Work of the 1441 Internet Assigned Numbers Authority", RFC 2860, June 2000. 1443 [RFC2929] Eastlake, D., Brunner-Williams, E. and B. Manning, "Domain 1444 Name System (DNS) IANA Considerations", RFC 2929, 1445 September 2000. 1447 [RFC2939] Droms, R., "Procedures and IANA Guidelines for Definition 1448 of New DHCP Options and Message Types", BCP 43, RFC 2939, 1449 September 2000. 1451 [RFC3228] Fenner, B., "IANA Considerations for IPv4 Internet Group 1452 Management Protocol (IGMP)", BCP 57, RFC 3228, February 1453 2002. 1455 [RFC3232] Reynolds, J., "Assigned Numbers: RFC 1700 is Replaced by 1456 an On-line Database", RFC 3232, January 2002. 1458 [RFC3552] Rescorla, E. and B. Korver, "Guidelines for Writing RFC 1459 Text on Security Considerations", BCP 72, RFC 3552, July 1460 2003. 1462 [RFC3575] Aboba, B., "IANA Considerations for RADIUS (Remote 1463 Authentication Dial In User Service)", RFC 3575, July 1464 2003. 1466 [RFC3692] Narten, T., "Assigning Experimental and Testing Numbers 1467 Considered Useful", BCP 82, RFC 3692, January 2004. 1469 [RFC3748] Aboba, B., Blunk, L., Vollbrecht, J., Carlson, J. and H. 1470 Levkowetz, "Extensible Authentication Protocol (EAP)", RFC 1471 3748, June 2004. 1473 [RFC3942] Volz, B., "Reclassifying Dynamic Host Configuration 1474 Protocol version 4 (DHCPv4) Options", RFC 3942, November 1475 2004. 1477 [RFC3968] Camarillo, G., "The Internet Assigned Number Authority 1478 (IANA) Header Field Parameter Registry for the Session 1479 Initiation Protocol (SIP)", BCP 98, RFC 3968, December 1480 2004. 1482 [RFC4005] Calhoun, P., Zorn, G., Spence, D. and D. Mitton, "Diameter 1483 Network Access Server Application", RFC 4005, August 2005. 1485 [RFC4025] Richardson, M., "A Method for Storing IPsec Keying 1486 Material in DNS", RFC 4025, March 2005. 1488 [RFC4044] McCloghrie, K., "Fibre Channel Management MIB", RFC 4044, 1489 May 2005. 1491 [RFC4124] Le Faucheur, F., "Protocol Extensions for Support of 1492 Diffserv-aware MPLS Traffic Engineering", RFC 4124, June 1493 2005. 1495 [RFC4169] Torvinen, V., Arkko, J. and M. Naslund, "Hypertext 1496 Transfer Protocol (HTTP) Digest Authentication Using 1497 Authentication and Key Agreement (AKA) Version-2", RFC 1498 4169, November 2005. 1500 [RFC4271] Rekhter, Y., Li, T. and S. Hares, "A Border Gateway 1501 Protocol 4 (BGP-4)", RFC 4271, January 2006. 1503 [RFC4283] Patel, A., Leung, K., Khalil, M., Akhtar, H. and K. 1504 Chowdhury, "Mobile Node Identifier Option for Mobile IPv6 1505 (MIPv6)", RFC 4283, November 2005. 1507 [RFC4288] Freed, N. and J. Klensin, "Media Type Specifications and 1508 Registration Procedures", BCP 13, RFC 4288, December 2005. 1510 [RFC4301] Kent, S. and K. Seo, "Security Architecture for the 1511 Internet Protocol", RFC 4301, December 2005. 1513 [RFC4340] Kohler, E., Handley, M. and S. Floyd, "Datagram Congestion 1514 Control Protocol (DCCP)", RFC 4340, March 2006. 1516 [RFC4395] Hansen, T., Hardie, T. and L. Masinter, "Guidelines and 1517 Registration Procedures for New URI Schemes", BCP 35, RFC 1518 4395, February 2006. 1520 [RFC4422] Melnikov, A. and K. Zeilenga, "Simple Authentication and 1521 Security Layer (SASL)", RFC 4422, June 2006. 1523 [RFC4446] Martini, L., "IANA Allocations for Pseudowire Edge to Edge 1524 Emulation (PWE3)", BCP 116, RFC 4446, April 2006. 1526 [RFC4520] Zeilenga, K., "Internet Assigned Numbers Authority (IANA) 1527 Considerations for the Lightweight Directory Access 1528 Protocol (LDAP)", BCP 64, RFC 4520, June 2006. 1530 [RFC4589] Schulzrinne, H. and H. Tschofenig, "Location Types 1531 Registry", RFC 4589, July 2006. 1533 [RFC4727] Fenner, B., "Experimental Values In IPv4, IPv6, ICMPv4, 1534 ICMPv6, UDP, and TCP Headers", RFC 4727, November 2006. 1536 [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security 1537 (TLS) Protocol Version 1.2", RFC 5246, August 2008. 1539 [RFC5378] Bradner, S. and J. Contreras, "Rights Contributors Provide 1540 to the IETF Trust", BCP 78, RFC 5378, November 2008. 1542 [RFC5742] Alvestrand, H. and R. Housley, "IESG Procedures for 1543 Handling of Independent and IRTF Stream Submissions", BCP 1544 92, RFC 5742, December 2009. 1546 [RFC5771] Cotton, M., Vegoda, L. and D. Meyer, "IANA Guidelines for 1547 IPv4 Multicast Address Assignments", BCP 51, RFC 5771, 1548 March 2010. 1550 [RFC5795] Sandlund, K., Pelletier, G. and L-E. Jonsson, "The RObust 1551 Header Compression (ROHC) Framework", RFC 5795, March 1552 2010. 1554 [RFC6195] Eastlake, D., "Domain Name System (DNS) IANA 1555 Considerations", BCP 42, RFC 6195, March 2011. 1557 [RFC6275] Perkins, C., Johnson, D. and J. Arkko, "Mobility Support 1558 in IPv6", RFC 6275, July 2011. 1560 [RFC6709] Carpenter, B., Aboba, B. and S. Cheshire, "Design 1561 Considerations for Protocol Extensions", RFC 6709, 1562 September 2012. 1564 Authors' Addresses 1566 Michelle Cotton, Manager, IANA Services 1567 Internet Corporation for Assigned Names and Numbers 1568 12025 Waterfront Drive, Suite 300 1569 Los Angeles, CA 90094-2536 1570 US 1572 Phone: +1 310 301 5812 1573 Email: michelle.cotton@icann.org 1575 Barry Leiba 1576 Huawei Technologies 1578 Phone: +1 646 827 0648 1579 Email: barryleiba@computer.org 1580 URI: http://internetmessagingtechnology.org/ 1582 Thomas Narten 1583 IBM Corporation 1584 3039 Cornwallis Ave., PO Box 12195 - BRQA/502 1585 Research Triangle Park, NC 27709-2195 1586 US 1588 Phone: +1 919 254 7798 1589 Email: narten@us.ibm.com