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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: January 31, 2014 IBM Corporation 8 August 01, 2013 10 Guidelines for Writing an IANA Considerations Section in RFCs 11 draft-leiba-cotton-iana-5226bis-03 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 make assignments in a given namespace prudently, IANA needs 23 guidance describing the conditions under which new values should be 24 assigned, as well as when and how modifications to existing values 25 can be made. This document defines a framework for the documentation 26 of these guidelines by specification authors, in order to assure that 27 the guidance given to IANA is clear and addresses the various issues 28 that 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." 46 This Internet-Draft will expire on January 31, 2014. 48 Copyright Notice 50 Copyright (c) 2013 IETF Trust and the persons identified as the 51 document authors. All rights reserved. 53 This document is subject to BCP 78 and the IETF Trust's Legal 54 Provisions Relating to IETF Documents (http://trustee.ietf.org/ 55 license-info) in effect on the date of publication of this document. 56 Please review these documents carefully, as they describe your rights 57 and restrictions with respect to this document. Code Components 58 extracted from this document must include Simplified BSD License text 59 as described in Section 4.e of the Trust Legal Provisions and are 60 provided without warranty as described in the Simplified BSD License. 62 Table of Contents 64 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 65 1.1. Terminology Used In This Document . . . . . . . . . . . . 3 66 2. Creating and Revising Registries . . . . . . . . . . . . . . . 4 67 2.1. Documentation Requirements for Registries . . . . . . . . 4 68 2.2. Defining an Appropriate Registry Policy . . . . . . . . . 6 69 2.2.1. Using the Well-Known Registration Policies . . . . . . 8 70 2.2.2. Using Multiple Policies in Combination . . . . . . . . 9 71 2.3. Revising Existing Registries . . . . . . . . . . . . . . . 10 72 3. Registering New Values in an Existing Registry . . . . . . . . 10 73 3.1. Documentation Requirements for Registrations . . . . . . . 10 74 3.2. Updating Existing Registrations . . . . . . . . . . . . . 12 75 3.3. Overriding Registration Procedures . . . . . . . . . . . . 12 76 4. Well-Known Registration Policies . . . . . . . . . . . . . . . 13 77 4.1. Private Use . . . . . . . . . . . . . . . . . . . . . . . 13 78 4.2. Experimental Use . . . . . . . . . . . . . . . . . . . . . 14 79 4.3. Hierarchical Allocation . . . . . . . . . . . . . . . . . 14 80 4.4. First Come First Served . . . . . . . . . . . . . . . . . 14 81 4.5. Expert Review . . . . . . . . . . . . . . . . . . . . . . 15 82 4.6. Specification Required . . . . . . . . . . . . . . . . . . 15 83 4.7. RFC Required . . . . . . . . . . . . . . . . . . . . . . . 16 84 4.8. IETF Review . . . . . . . . . . . . . . . . . . . . . . . 16 85 4.9. Standards Action . . . . . . . . . . . . . . . . . . . . . 16 86 4.10. IESG Approval . . . . . . . . . . . . . . . . . . . . . . 17 87 5. Designated Experts . . . . . . . . . . . . . . . . . . . . . . 17 88 5.1. The Motivation for Designated Experts . . . . . . . . . . 17 89 5.2. The Role of the Designated Expert . . . . . . . . . . . . 18 90 5.3. Designated Expert Reviews . . . . . . . . . . . . . . . . 19 91 5.4. Expert Reviews and the Document Lifecycle . . . . . . . . 21 92 6. Well-Known Registration Status Terminology . . . . . . . . . . 21 93 7. Documentation References in IANA Registries . . . . . . . . . 22 94 8. What to Do in "bis" Documents . . . . . . . . . . . . . . . . 22 95 9. Miscellaneous Issues . . . . . . . . . . . . . . . . . . . . . 23 96 9.1. When There Are No IANA Actions . . . . . . . . . . . . . . 23 97 9.2. Namespaces Lacking Documented Guidance . . . . . . . . . . 24 98 9.3. After-the-Fact Registrations . . . . . . . . . . . . . . . 24 99 9.4. Reclaiming Assigned Values . . . . . . . . . . . . . . . . 25 100 9.5. Contact Person vs Assignee or Owner . . . . . . . . . . . 25 101 9.6. Closing or Obsoleting a Registry . . . . . . . . . . . . . 26 102 10. Appeals . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 103 11. Mailing Lists . . . . . . . . . . . . . . . . . . . . . . . . 26 104 12. Security Considerations . . . . . . . . . . . . . . . . . . . 26 105 13. To-Do List; resolve and remove before requesting publication . 27 106 14. Changes Relative to Earlier Editions of BCP 26 . . . . . . . . 27 107 14.1. 2013: Changes in This Document Relative to RFC 5226 . . . 27 108 14.2. 2008: Changes in RFC 5226 Relative to RFC 2434 . . . . . 28 109 15. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 28 110 15.1. Acknowledgments for This Document (2013) . . . . . . . . 28 111 15.2. Acknowledgments from the second edition (2008) . . . . . 29 112 15.3. Acknowledgments from the first edition (1998) . . . . . . 29 113 16. References . . . . . . . . . . . . . . . . . . . . . . . . . . 29 114 16.1. Normative References . . . . . . . . . . . . . . . . . . 29 115 16.2. Informative References . . . . . . . . . . . . . . . . . 29 116 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 32 118 1. Introduction 120 Many protocols make use of points of extensibility that use constants 121 to identify various protocol parameters. To ensure that the values 122 used in these fields do not have conflicting uses, and to promote 123 interoperability, their allocation is often coordinated by a central 124 authority. For IETF protocols, that role is filled by the Internet 125 Assigned Numbers Authority (IANA) [RFC2860]. IANA services are 126 currently provided by the International Corporation for Assigned 127 Names and Numbers (ICANN). 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. The terms "assignment" and "registration" are used 139 interchangably throughout this document. 141 To make assignments in a given namespace prudently, IANA needs 142 guidance describing the conditions under which new values should be 143 assigned, as well as when and how modifications to existing values 144 can be made. This document defines a framework for the documentation 145 of these guidelines by specification authors, in order to assure that 146 the guidance given to IANA is clear and addresses the various issues 147 that are likely in the operation of a registry. 149 Typically, this information is recorded in a dedicated section of the 150 specification with the title "IANA Considerations". 152 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 162 Defining a registry involves describing the namespace(s) to be 163 created, listing an initial set of assignments (if appropriate), and 164 documenting guidelines on how future assignments are to be made. 166 Before defining a registry, however, consider delegating the 167 namespace in some manner. This route should be pursued when 168 appropriate, as it lessens the burden on IANA for dealing with 169 assignments. 171 In particular, not all namespaces require a registry; in some cases, 172 assignments can be made independently and with no further (central) 173 coordination. In the Domain Name System, for example, IANA only 174 deals with assignments at the higher levels, while subdomains are 175 administered by the organization to which the space has been 176 delegated. When a namespace is delegated in this manner, the scope 177 of IANA is limited to the parts of the namespace where IANA has 178 authority. 180 2.1. Documentation Requirements for Registries 182 Documents that create a new namespace (or modify the definition of an 183 existing space) and that expect IANA to play a role in maintaining 184 that space (serving as a repository for registered values) MUST 185 provide clear instructions on details of the namespace, either in the 186 IANA Considerations section, or referenced from it. 188 In particular, such instructions MUST include: 190 The name of the registry (or sub-registry) 191 This name will appear on the IANA web page and will be referred to 192 in future documents that need to allocate a value from the new 193 space. The full name (and abbreviation, if appropriate) should be 194 provided. It is highly desirable that the chosen name not be 195 easily confused with the name of another registry. 197 When creating a sub-registry, the registry that it is a part of 198 must be identified using its full name, exactly as it appears in 199 the IANA registry list. 201 Providing a URL to precisely identify the registry helps IANA 202 understand the request. Such URLs are usually removed from the 203 RFC prior to final publication. 205 For example, a document could contain something like this: 207 [TO BE REMOVED: This registration should be made in the Foobar 208 Operational Parameters registry, located at http://www.iana.org 209 /assignments/foobar-registry] 211 Required information for registrations 213 This information may include the need to document relevant 214 Security Considerations, if any. 216 Applicable review process 218 The review process that will apply to all future requests for 219 registration. See Section 2.2. 221 Size, format and syntax of registry entries 223 What fields to record in the registry., and any technical 224 requirements upon registry entries (e.g., valid ranges for 225 integers, length limitations on strings, etc.) as well as the 226 exact format in which registry values should be displayed. For 227 numeric assignments, one should specify whether values are to be 228 recorded in decimal, hexadecimal, or some other format. For 229 strings, the encoding format should be specified (ASCII, UTF8, 230 etc.). 232 Initial assignments and reservations 234 Any initial assignments or registrations to be included. In 235 addition, any ranges that are to be reserved for "Private Use", 236 "Reserved", "Unassigned", etc. should be indicated. 238 For example, a document might specify a new registry by including: 240 --------------------------------------------------------------- 242 X. IANA Considerations 244 This document defines a new DHCP option, entitled "FooBar" (see 245 Section y), assigned a value of TBD1 from the DHCP Option space 246 [to be removed upon publication: 247 http://www.iana.org/assignments/bootp-dhcp-parameters] 248 [RFC2132] [RFC2939]: 249 Data 250 Tag Name Length Meaning 251 ---- ---- ------ ------- 252 TBD1 FooBar N FooBar server 254 The FooBar option also defines an 8-bit FooType field, for which 255 IANA is to create and maintain a new sub-registry entitled 256 "FooType values" under the FooBar option. Initial values for the 257 DHCP FooBar FooType registry are given below; future assignments 258 are to be made through Expert Review [BCP26]. 259 Assignments consist of a DHCP FooBar FooType name and its 260 associated value. 262 Value DHCP FooBar FooType Name Definition 263 ---- ------------------------ ---------- 264 0 Reserved 265 1 Frobnitz See Section y.1 266 2 NitzFrob See Section y.2 267 3-254 Unassigned 268 255 Reserved 269 --------------------------------------------------------------- 271 For examples of documents that establish registries, consult 272 [RFC6195], [RFC3575], [RFC3968], and [RFC4520]. 274 2.2. Defining an Appropriate Registry Policy 276 There are several issues to consider when defining the policy for the 277 new assignments in a registry. 279 If the registry's namespace is limited, assignments will need to be 280 made carefully to prevent exhaustion. 282 Even when the space is essentially unlimited, however, it is usually 283 desirable to have at least a minimal review prior to assignment in 284 order to: 286 o prevent the hoarding of or unnecessary wasting of values. For 287 example, if the space consists of text strings, it may be 288 desirable to prevent entities from obtaining large sets of strings 289 that correspond to desirable names (existing company names, for 290 example). 292 o provide a sanity check that the request actually makes sense and 293 is necessary. Experience has shown that some level of minimal 294 review from a subject matter expert is useful to prevent 295 assignments in cases where the request is malformed or not 296 actually needed (for example, an existing assignment for an 297 essentially equivalent service already exists). 299 Perhaps most importantly, unreviewed extensions can impact 300 interoperability and security. See [RFC6709]. 302 When the namespace is essentially unlimited and there are no 303 potential interoperability or security issues, assigned numbers can 304 usually be given out to anyone without any subjective review. In 305 such cases, IANA can make assignments directly, provided that IANA is 306 given detailed instructions on what types of requests it should 307 grant, and it is able to do so without exercising subjective 308 judgement. 310 When this is not the case, some level of review is required. 311 However, it's important to balance adequate review and ease of 312 registration. In many cases, those making registrations will not be 313 IETF participants; requests often come from other standards 314 organizations, from organizations not directly involved in standards, 315 from ad-hoc community work (from an open-source project, for 316 example), and so on. Registration must not be unnecessarily 317 difficult, unnecessarily costly (in terms of time and other 318 resources), nor unnecessarily subject to denial. 320 While it is sometimes necessary to restrict what gets registered 321 (e.g., for limited resources such as bits in a byte, or for items for 322 which unsupported values can be damaging to protocol operation), in 323 many cases having what's in use represented in the registry is more 324 important. Overly strict review criteria and excessive cost (in time 325 and effort) discourage people from even attempting to make a 326 registration. If a registry fails to reflect the protocol elements 327 actually in use, it can adversely affect deployment of protocols on 328 the Internet, and the registry itself is devalued. 330 In particular, when a registry policy that requires involvement of 331 Working Groups, directorates, or other bodies to be actively involved 332 and to support the effort, requests frequently run into concerns that 333 "it's not worth doing a Standards-Track RFC for something this 334 trivial," when, in fact, that requirement was created by the Working 335 Group in the first place, by placing the bar that high. 337 Indeed, publishing any RFC is costly, and a Standards Track RFC is 338 especially so, requiring a great deal of community time for review 339 and discussion, IETF-wide last call, involvement of the entire IESG 340 as well as concentrated time and review from the sponsoring AD, 341 review and action by IANA, and RFC-Editor processing. 343 Therefore, Working Groups and other document developers should use 344 care in selecting appropriate registration policies when their 345 documents create registries. They should select the least strict 346 policy that suits a registry's needs, and look for specific 347 justification for policies that require significant community 348 involvement (Specification Required, in terms of the well-known 349 policies). 351 2.2.1. Using the Well-Known Registration Policies 353 This document defines a number of registration policies in Section 4. 354 Because they benefit from both community experience and wide 355 understanding, their use is encouraged when appropriate. 357 It is also acceptable to cite one of the well-known policies and 358 include additional guidelines for what kind of considerations should 359 be taken into account by the review process. 361 For example, RADIUS [RFC3575] specifies the use of a Designated 362 Expert, but includes specific additional criteria the Designated 363 Expert should follow. 365 The well-known policies from "First Come First Served" to "Standards 366 Action" specify a range of policies in increasing order of 367 strictness: 369 4. First Come First Served 370 No review, minimal documentation. 372 5. Expert Review 373 Expert review, sufficient documentation for review. 375 6. Specification Required 376 Expert review, significant, stable public documentation. 378 7. RFC Required 379 Any RFC publication, IETF or a non-IETF Stream. 381 8. IETF Review 382 RFC publication, IETF Stream only, but need not be Standards 383 Track. 385 9. Standards Action 386 RFC publication, IETF Stream, Standards Track only. 388 Examples of situations that might merit RFC Required, IETF Review, or 389 Standards Action include the following: 391 o When a resource is limited, such as bits in a byte (or in two 392 bytes, or four), or numbers in a limited range. In these cases, 393 allowing registrations that haven't been carefully reviewed and 394 agreed by community consensus could too quickly deplete the 395 allowable values. 397 o When thorough community review is necessary to avoid extending or 398 modifying the protocol in ways that could be damaging. One 399 example is in defining new command codes, as opposed to options 400 that use existing command codes: the former might require a strict 401 policy, where a more relaxed policy could be adequate for the 402 latter. Another example is in defining protocol elements that 403 change the semantics of existing operations. 405 The description in Section 4.10 of "IESG Approval" suggests that the 406 IESG "can (and should) reject a request if another path for 407 registration is available that is more appropriate and there is no 408 compelling reason not to use that path." The IESG should give 409 similar consideration to any registration policy more stringent than 410 Specification Required, asking for justification and ensuring that 411 more relaxed policies have been considered, and the strict policy is 412 the right one. 414 Accordingly, document developers need to anticipate this and document 415 their considerations for selecting the specified policy (ideally, in 416 the document itself; failing that, in the shepherd writeup). 417 Likewise, the document shepherd should ensure that the selected 418 policies have been justified before sending the document to the IESG. 420 When specifications are revised, registration policies should be 421 reviewed in light of experience since the policies were set. 423 Note that the well-known policies are not exclusive; there are 424 situations where a different policy might be more appropriate. 426 2.2.2. Using Multiple Policies in Combination 428 In some situations, it is necessary to define multiple registration 429 policies. For example, registrations through the normal IETF process 430 might use one policy, while registrations from outside the process 431 would have a different policy applied. 433 Thus, a particular registry might want to use a policy such as "RFC 434 Required" or "IETF Review" sometimes, with a designated expert 435 checking a "Specification Required" policy at other times. 437 The alternative to using a combination requires either that all 438 requests come through RFCs or that requests in RFCs go through review 439 by the designated expert, even though they already have IETF review 440 and consensus. 442 This can be documented in the IANA Considerations section when the 443 registry is created: 445 IANA is asked to create the registry "Fruit Access Flags" as a 446 sub-registry of "Fruit Parameters". New registrations will be 447 permitted through either the IETF Review policy or the 448 Specification Required policy [BCP26]. 450 Such combinations will commonly use one of {Standards Action, IETF 451 Review, RFC Required} in combination with one of {Specification 452 Required, Expert Review}. 454 2.3. Revising Existing Registries 456 Updating the registration process for an already existing (previously 457 created) namespace (whether created explicitly or implicitly) follows 458 a process similar to that used when creating a new namespace. That 459 is, a document is produced that makes reference to the existing 460 namespace and then provides detailed guidelines for handling 461 assignments in each individual namespace. Such documents are 462 normally processed as Best Current Practices (BCPs) [RFC2026]. 464 Example documents that updated the guidelines for assignments in pre- 465 existing registries include: [RFC6195], [RFC3228], and [RFC3575]. 467 3. Registering New Values in an Existing Registry 469 3.1. Documentation Requirements for Registrations 471 Often, documents request an assignment from an already existing 472 namespace (one created by a previously published document). 474 Such documents should clearly identify the namespace in which each 475 value is to be registered. If the registration goes into a sub- 476 registry, the author should clearly describe where the assignment or 477 registration should go. Use the exact namespace name as listed on 478 the IANA web page, and cite the RFC where the namespace is defined. 480 There is no need to mention what the assignment policy for new 481 assignments is, as that should be clear from the references. 483 When referring to an existing registry, providing a URL to precisely 484 identify the registry is helpful. Such URLs, however, should usually 485 be removed from the RFC prior to final publication, since IANA URLs 486 are not guaranteed to be stable in the future. In cases where it is 487 important to include a URL in the document, IANA should concur on its 488 inclusion. 490 For example, a document could contain something like this: 492 [TO BE REMOVED: This registration should be made in the Foobar 493 Operational Parameters registry, located at http://www.iana.org/ 494 assignments/foobar-registry] 496 Each value requested should be given a unique reference. When the 497 value is numeric, use the notation: TBD1, TBD2, etc. Throughout the 498 document where an actual IANA-assigned value should be filled in, use 499 the "TBDx" notation. This helps ensure that the final RFC has the 500 correct assigned values inserted in all of the relevant places where 501 the value is expected to appear in the final document. For values 502 that are text strings, a specific name can be suggested. IANA will 503 normally assign the name, unless it conflicts with a name already in 504 use. 506 Normally, the values to be used are chosen by IANA and documents 507 should specify values of "TBD". However, in some cases, a value may 508 have been used for testing or in early implementations. In such 509 cases, it is acceptable to include text suggesting what specific 510 value should be used (together with the reason for the choice). For 511 example, one might include the text "the value XXX is suggested as it 512 is used in implementations". However, it should be noted that 513 suggested values are just that; IANA will attempt to assign them, but 514 may find that impossible, if the proposed number has already been 515 assigned for some other use. 517 For some registries, IANA has a long-standing policy prohibiting 518 assignment of names or codes on a vanity or organization-name basis. 519 For example, codes are always assigned sequentially unless there is a 520 strong reason for making an exception. Nothing in this document is 521 intended to change those policies or prevent their future 522 application. 524 The IANA Considerations section should summarize all of the IANA 525 actions, with pointers to the relevant sections elsewhere in the 526 document as appropriate. When multiple values are requested, it is 527 generally helpful to include a summary table. It is also helpful for 528 this table to be in the same format as it appears or will appear on 529 the IANA web site. For example: 531 Value Description Reference 532 -------- ------------------- --------- 533 TBD1 Foobar [[this RFC]] 535 Note: In cases where authors feel that including the full table is 536 too verbose or repetitive, authors should still include the table in 537 the draft, but may include a note asking that the table be removed 538 prior to publication of the final RFC. 540 As an example, the following text could be used to request assignment 541 of a DHCPv6 option number: 543 IANA has assigned an option code value of TBD1 to the DNS 544 Recursive Name Server option and an option code value of TBD2 to 545 the Domain Search List option from the DHCP option code space 546 defined in Section 24.3 of RFC 3315. 548 3.2. Updating Existing Registrations 550 Even after a number has been assigned, some types of registrations 551 contain additional information that may need to be updated over time. 553 For example, MIME media types, character sets, and language tags 554 typically include more information than just the registered value 555 itself, and may need things such as point-of-contact information, 556 security issues, pointers to updates, or literature references 557 updated. 559 In such cases, the document defining the namespace must clearly state 560 who is responsible for maintaining and updating a registration. 561 Depending on the registry, it may be appropriate to specify one or 562 more of: 564 o Letting registrants and/or nominated change controllers update 565 their own registrations, subject to the same constraints and 566 review as with new registrations. 568 o Allowing attachment of comments to the registration. This can be 569 useful in cases where others have significant objections to a 570 registration, but the author does not agree to change the 571 registration. 573 o Designating the IESG, a designated expert, or another entity as 574 having the right to change the registrant associated with a 575 registration and any requirements or conditions on doing so. This 576 is mainly to get around the problem when a registrant cannot be 577 reached in order to make necessary updates. 579 3.3. Overriding Registration Procedures 581 Experience has shown that the documented IANA considerations for 582 individual protocols do not always adequately cover the reality of 583 registry operation, or are not sufficiently clear. In addition, 584 documented IANA considerations are sometimes found to be too 585 stringent to allow even working group documents (for which there is 586 strong consensus) to perform a registration in advance of actual RFC 587 publication. 589 In order to allow assignments in such cases, the IESG is granted 590 authority to override registration procedures and approve assignments 591 on a case-by-case basis. 593 The intention here is not to overrule properly documented procedures, 594 or to obviate the need for protocols to properly document their IANA 595 considerations. Rather, it is to permit assignments in specific 596 cases where it is obvious that the assignment should just be made, 597 but updating the IANA process beforehand is too onerous. 599 When the IESG is required to take action as described in this 600 section, it is a strong indicator that the applicable registration 601 procedures should be updated, possibly in parallel with the work that 602 instigated it. 604 4. Well-Known Registration Policies 606 The following are some defined policies, most of which are in use 607 today. These cover a range of typical policies that have been used 608 to describe the procedure for assigning new values in a namespace. 609 It is not strictly required that documents use these terms; the 610 actual requirement is that the instructions to IANA be clear and 611 unambiguous. However, use of these terms is strongly RECOMMENDED, 612 because their meanings are widely understood. The terms are fully 613 explained in the following subsections. 615 1. Private Use 616 2. Experimental Use 617 3. Hierarchical Allocation 618 4. First Come First Served 619 5. Expert Review 620 6. Specification Required 621 7. RFC Required 622 8. IETF Review 623 9. Standards Action 624 10. IESG Approval 626 It should be noted that it often makes sense to partition a namespace 627 into multiple categories, with assignments within each category 628 handled differently. Many protocols now partition namespaces into 629 two or more parts, with one range reserved for Private or 630 Experimental Use while other ranges are reserved for globally unique 631 assignments assigned following some review process. Dividing a 632 namespace into ranges makes it possible to have different policies in 633 place for different ranges and different use cases. 635 Similarly, it will often be useful to specify multiple policies in 636 parallel, with each policy being used under different circumstances. 637 For more discussion of that topic, see Section 2.2.2. 639 Examples: 641 LDAP [RFC4520] 642 TLS ClientCertificateType Identifiers [RFC5246] (as detailed in 643 the subsections below) 644 Pseudowire Edge to Edge Emulation (PWE3) [RFC4446] 646 4.1. Private Use 647 For private or local use only, with the type and purpose defined by 648 the local site. No attempt is made to prevent multiple sites from 649 using the same value in different (and incompatible) ways. There is 650 no need for IANA to review such assignments (since IANA does not 651 record them) and assignments are not generally useful for broad 652 interoperability. It is the responsibility of the sites making use 653 of the Private Use range to ensure that no conflicts occur (within 654 the intended scope of use). 656 Examples: 658 Site-specific options in DHCP [RFC2939] 659 Fibre Channel Port Type Registry [RFC4044] 660 TLS ClientCertificateType Identifiers 224-255 [RFC5246] 662 4.2. Experimental Use 664 Experimental Use is similar to Private Use only, but with the purpose 665 being to facilitate experimentation. See [RFC3692] for details. 667 Example: 669 Experimental Values in IPv4, IPv6, ICMPv4, ICMPv6, UDP, and TCP 670 Headers [RFC4727] 672 4.3. Hierarchical Allocation 674 With Hierarchical Allocation, delegated administrators are given 675 control over part of the namespace, and can assign values in that 676 part of the namespace. IANA makes allocations in the higher levels 677 of the namespace according to one of the other policies. 679 Examples: 681 DNS names 682 Object Identifiers 683 IP addresses 685 4.4. First Come First Served 687 For the First Come First Served policy, assignments are made to 688 anyone on a first come, first served basis. There is no substantive 689 review of the request, other than to ensure that it is well-formed 690 and doesn't duplicate an existing assignment. However, requests must 691 include a minimal amount of clerical information, such as a point of 692 contact (including an email address, and sometimes a postal address) 693 and a brief description of how the value will be used. Additional 694 information specific to the type of value requested may also need to 695 be provided, as defined by the namespace. For numbers, the exact 696 value is generally assigned by IANA; with names, specific text 697 strings can usually be requested. 699 Examples: 701 SASL mechanism names [RFC4422] 702 LDAP Protocol Mechanisms and LDAP Syntax [RFC4520] 704 4.5. Expert Review 706 (Also called "Designated Expert" in earlier editions of this 707 document.) For the Expert Review policy, review and approval by a 708 designated expert (see Section 5) is required. The required 709 documentation and review criteria for use by the designated expert 710 should be provided when defining the registry. For example, see 711 Sections 6 and 7.2 in [RFC3748]. 713 It is particularly important, when using a designated expert, to give 714 clear guidance to the expert, laying out criteria for performing an 715 evaluation and reasons for rejecting a request. When specifying a 716 policy that involves a designated expert, the IANA Considerations 717 SHOULD contain such guidance. It is also a good idea to include, 718 when possible, a sense of whether many registrations are expected 719 over time, or if the registry is expected to be updated infrequently 720 or in exceptional circumstances only. 722 Examples: 724 EAP Method Types [RFC3748] 725 HTTP Digest AKA algorithm versions [RFC4169] 726 URI schemes [RFC4395] 727 GEOPRIV Location Types [RFC4589] 729 4.6. Specification Required 731 For the Specification Required policy, review and approval by a 732 designated expert (see Section 5) is required, and the values and 733 their meanings must be documented in a permanent and readily 734 available public specification, in sufficient detail so that 735 interoperability between independent implementations is possible. 736 The designated expert will review the public specification and 737 evaluate whether it is sufficiently clear to allow interoperable 738 implementations. The intention behind "permanent and readily 739 available" is that a document can reasonably be expected to be 740 findable and retrievable long after IANA assignment of the requested 741 value. Publication of an RFC is an ideal means of achieving this 742 requirement, but Specification Required is intended to also cover the 743 case of a document published outside of the RFC path. For RFC 744 publication, the normal RFC review process is expected to provide the 745 necessary review for interoperability, though the designated expert 746 may be a particularly well-qualified person to perform such a review. 748 When specifying this policy, just use the term "Specification 749 Required". Some specifications have chosen to refer to it as "Expert 750 Review with Specification Required", and that only causes confusion. 752 Examples: 754 Diffserv-aware TE Bandwidth Constraints Model Identifiers 755 [RFC4124] 756 TLS ClientCertificateType Identifiers 64-223 [RFC5246] 757 ROHC Profile Identifiers [RFC5795] 759 4.7. RFC Required 761 With the RFC Required policy, the registration request, along with 762 associated documentation, must be published in an RFC. The RFC need 763 not be in the IETF stream, but may be in any RFC stream (currently an 764 RFC may be in the IETF, IRTF, or IAB stream, or an RFC Editor 765 Independent Submission [RFC5742]). Unless otherwise specified, any 766 type of RFC is sufficient (currently Standards Track, BCP, 767 Informational, Experimental, or Historic). 769 4.8. IETF Review 771 (Formerly called "IETF Consensus" in the first edition of this 772 document.) With the IETF Review policy, new values are assigned only 773 through RFCs in the IETF Stream -- those that have been shepherded 774 through the IESG as AD-Sponsored or IETF working group Documents 775 [RFC2026] [RFC5378]. 777 The intent is that the document and proposed assignment will be 778 reviewed by the IETF community (including appropriate IETF working 779 groups, directorates, and other experts) and by the IESG, to ensure 780 that the proposed assignment will not negatively affect 781 interoperability or otherwise extend IETF protocols in an 782 inappropriate or damaging manner. To ensure adequate community 783 review, such documents will always undergo an IETF Last Call. 785 Examples: 787 IPSECKEY Algorithm Types [RFC4025] 788 Accounting-Auth-Method AVP values in DIAMETER [RFC4005] 789 TLS Extension Types [RFC5246] 791 4.9. Standards Action 793 For the Standards Action policy, values are assigned only through 794 Standards Track RFCs approved by the IESG. 796 Examples: 798 BGP message types [RFC4271] 799 Mobile Node Identifier option types [RFC4283] 800 TLS ClientCertificateType Identifiers 0-63 [RFC5246] 801 DCCP Packet Types [RFC4340] 803 4.10. IESG Approval 805 New assignments may be approved by the IESG. Although there is no 806 requirement that the request be documented in an RFC, the IESG has 807 discretion to request documents or other supporting materials on a 808 case-by-case basis. 810 IESG Approval is not intended to be used often or as a "common case"; 811 indeed, it has seldom been used in practice during the period RFC 812 2434 was in effect. Rather, it is intended to be available in 813 conjunction with other policies as a fall-back mechanism in the case 814 where one of the other allowable approval mechanisms cannot be 815 employed in a timely fashion or for some other compelling reason. 816 IESG Approval is not intended to circumvent the public review 817 processes implied by other policies that could have been employed for 818 a particular assignment. IESG Approval would be appropriate, 819 however, in cases where expediency is desired and there is strong 820 consensus (such as from a working group) for making the assignment. 822 The following guidelines are suggested for any evaluation under IESG 823 Approval: 825 o The IESG can (and should) reject a request if another path for 826 registration is available that is more appropriate and there is no 827 compelling reason not to use that path. 829 o Before approving a request, the community should be consulted, via 830 a "call for comments" that provides as much information as is 831 reasonably possible about the request. 833 Examples: 835 IPv4 Multicast address assignments [RFC5771] 836 IPv4 IGMP Type and Code values [RFC3228] 837 Mobile IPv6 Mobility Header Type and Option values [RFC6275] 839 5. Designated Experts 841 5.1. The Motivation for Designated Experts 843 IANA does not define registry policy itself; rather, it carries out 844 policies that have been defined by others and published in RFCs. As 845 part of that process, review of proposed registrations is often 846 appropriate. 848 A common way to ensure such review is for a proposed registration to 849 be published as an RFC, as this ensures that the specification is 850 publicly and permanently available. It is particularly important if 851 any potential interoperability issues might arise. For example, some 852 assignments are not just assignments, but also involve an element of 853 protocol specification. A new option may define fields that need to 854 be parsed and acted on, which (if specified poorly) may not fit 855 cleanly with the architecture of other options or the base protocols 856 on which they are built. 858 In some cases, however, the burden of publishing an RFC in order to 859 register a protocol element is excessive. 861 However, it is generally still useful (and sometimes necessary) to 862 discuss proposed registrations within the community, on a mailing 863 list. Such a mailing list provides opportunity for public review 864 prior to assignment, and allows for a consultative process when 865 registrants want help in understanding what a proper registration 866 should contain. 868 While discussion on a mailing list can provide valuable technical 869 feedback, opinions may vary and discussions may continue for some 870 time without clear resolution. In addition, IANA cannot participate 871 in all of these mailing lists and cannot determine if or when such 872 discussions reach consensus. Therefore, IANA relies on a "designated 873 expert" for advice regarding the specific question of whether an 874 assignment should be made. The designated expert is an individual 875 who is responsible for carrying out an appropriate evaluation and 876 returning a recommendation to IANA. 878 It should be noted that a key motivation for having designated 879 experts is for the IETF to provide IANA with a subject matter expert 880 to whom the evaluation process can be delegated. IANA forwards 881 requests for an assignment to the expert for evaluation, and the 882 expert (after performing the evaluation) informs IANA as to whether 883 or not to make the assignment or registration. 885 It will often be useful to use a designated expert only some of the 886 time, as a supplement to other processes. For more discussion of 887 that topic, see Section 2.2.2. 889 5.2. The Role of the Designated Expert 891 The designated expert is responsible for coordinating the appropriate 892 review of an assignment request. The review may be wide or narrow, 893 depending on the situation and the judgment of the designated expert. 894 This may involve consultation with a set of technology experts, 895 discussion on a public mailing list, consultation with a working 896 group (or its mailing list if the working group has disbanded), etc. 897 Ideally, the designated expert follows specific review criteria as 898 documented with the protocol that creates or uses the namespace. See 899 the IANA Considerations sections of [RFC3748] and [RFC3575] for 900 specific examples. 902 Designated experts are expected to be able to defend their decisions 903 to the IETF community, and the evaluation process is not intended to 904 be secretive or bestow unquestioned power on the expert. Experts are 905 expected to apply applicable documented review or vetting procedures, 906 or in the absence of documented criteria, follow generally accepted 907 norms such as those in Section 5.3. 909 Section 3.2 discusses disputes and appeals in more detail. 911 Designated experts are appointed by the IESG (normally upon 912 recommendation by the relevant Area Director). They are typically 913 named at the time a document creating or updating a namespace is 914 approved by the IESG, but as experts originally appointed may later 915 become unavailable, the IESG will appoint replacements if necessary. 917 For some registries, it has proven useful to have multiple designated 918 experts. Sometimes those experts work together in evaluating a 919 request, while in other cases additional experts serve as backups. 920 In cases of disagreement among those experts, it is the 921 responsibility of those experts to make a single clear recommendation 922 to IANA. It is not appropriate for IANA to resolve disputes among 923 experts. In extreme situations, such as deadlock, the IESG may need 924 to step in to resolve the problem. 926 In registries where a pool of experts evaluates requests, the pool 927 should have a single chair responsible for defining how requests are 928 to be assigned to and reviewed by experts. In some cases, the expert 929 pool may consist of a primary and backups, with the backups involved 930 only when the primary expert is unavailable. In other cases, IANA 931 might assign requests to individual members in sequential or 932 approximate random order. In the event that IANA finds itself having 933 received conflicting advice from its experts, it is the 934 responsibility of the pool's chair to resolve the issue and provide 935 IANA with clear instructions. 937 Since the designated experts are appointed by the IESG, they may be 938 removed by the IESG. 940 5.3. Designated Expert Reviews 942 In the years since RFC 2434 was published and has been put to use, 943 experience has led to the following observations: 945 o A designated expert must respond in a timely fashion, normally 946 within a week for simple requests to a few weeks for more complex 947 ones. Unreasonable delays can cause significant problems for 948 those needing assignments, such as when products need code points 949 to ship. This is not to say that all reviews can be completed 950 under a firm deadline, but they must be started, and the requester 951 and IANA should have some transparency into the process if an 952 answer cannot be given quickly. 954 o If a designated expert does not respond to IANA's requests within 955 a reasonable period of time, either with a response or with a 956 reasonable explanation for the delay (some requests may be 957 particularly complex), and if this is a recurring event, IANA must 958 raise the issue with the IESG. Because of the problems caused by 959 delayed evaluations and assignments, the IESG should take 960 appropriate actions to ensure that the expert understands and 961 accepts his or her responsibilities, or appoint a new expert. 963 o The designated expert is not required to personally bear the 964 burden of evaluating and deciding all requests, but acts as a 965 shepherd for the request, enlisting the help of others as 966 appropriate. In the case that a request is denied, and rejecting 967 the request is likely to be controversial, the expert should have 968 the support of other subject matter experts. That is, the expert 969 must be able to defend a decision to the community as a whole. 971 When a designated expert is used, the documentation should give clear 972 guidance to the designated expert, laying out criteria for performing 973 an evaluation and reasons for rejecting a request. In the case where 974 there are no specific documented criteria, the presumption should be 975 that a code point should be granted unless there is a compelling 976 reason to the contrary. Possible reasons to deny a request include 977 these: 979 o Scarcity of code points, where the finite remaining code points 980 should be prudently managed, or when a request for a large number 981 of code points is made, when a single code point is the norm. 983 o Documentation is not of sufficient clarity to evaluate or ensure 984 interoperability. 986 o The code point is needed for a protocol extension, but the 987 extension is not consistent with the documented (or generally 988 understood) architecture of the base protocol being extended, and 989 would be harmful to the protocol if widely deployed. It is not 990 the intent that "inconsistencies" refer to minor differences "of a 991 personal preference nature". Instead, they refer to significant 992 differences such as inconsistencies with the underlying security 993 model, implying a change to the semantics of an existing message 994 type or operation, requiring unwarranted changes in deployed 995 systems (compared with alternate ways of achieving a similar 996 result), etc. 998 o The extension would cause problems with existing deployed systems. 1000 o The extension would conflict with one under active development by 1001 the IETF, and having both would harm rather than foster 1002 interoperability. 1004 When a designated expert is used, documents MUST NOT name the 1005 designated expert in the document itself; instead, any suggested 1006 names should be relayed to the appropriate Area Director at the time 1007 the document is sent to the IESG for approval. This is usually done 1008 in the document shepherd writeup. 1010 If the request should also be reviewed on a specific public mailing 1011 list, its address should be specified. 1013 5.4. Expert Reviews and the Document Lifecycle 1015 Review by the designated expert is necessarily done at a particular 1016 point in time, and represents review of a particular version of the 1017 document. Deciding when the review should take place is a question 1018 of good judgment. And while re-reviews might be done when it's 1019 acknowledged that the documentation of the registered item has 1020 changed substantially, making sure that re-review happens requires 1021 attention and care. 1023 It is possible, through carelessness, accident, inattentiveness, or 1024 even willful disregard, that changes might be made after the 1025 designated expert's review and approval that would, if the document 1026 were re-reviewed, cause the expert not to approve the registration. 1027 It is up to the IESG, with the token held by the responsible Area 1028 Director, to be alert to such situations and to recognize that such 1029 changes need to be checked. 1031 6. Well-Known Registration Status Terminology 1033 The following labels describe the status of an assignment or range of 1034 assignments: 1036 Private Use: Private use only (not assigned), as described in 1037 Section 4.1. 1039 Experimental: Available for general experimental use as described 1040 in [RFC3692]. IANA does not record specific assignments for 1041 any particular use. 1043 Unassigned: Not currently assigned, and available for assignment 1044 via documented procedures. While it's generally clear that 1045 any values that are not registered are unassigned and 1046 available for assignment, it is sometimes useful to 1047 explicitly specify that situation. Note that this is 1048 distinctly different from "Reserved". 1050 Reserved: Not assigned and not available for assignment. Reserved 1051 values are held for special uses, such as to extend the 1052 namespace when it becomes exhausted. Note that this is 1053 distinctly different from "Unassigned". 1055 7. Documentation References in IANA Registries 1057 Usually, registries and registry entries include references to 1058 documentation (RFCs or other documents). The purpose of these 1059 references is to provide pointers for implementors to find details 1060 necessary for implementation, NOT to simply note what document 1061 created the registry or entry. Therefore: 1063 o If a document registers an item that is defined and explained 1064 elsewhere, the registered reference should be to that document, 1065 and not to the document that is merely performing the 1066 registration. 1068 o If the registered item is defined and explained in the current 1069 document, it is important to include sufficient information to 1070 enable implementors to understand the item and to create a proper 1071 implementation. 1073 o If the registered item is explained primarily in a specific 1074 section of the reference document, it is useful to include a 1075 section reference. For example, "[RFC9876], Section 3.2", rather 1076 than just "[RFC9876]". 1078 o For documentation of a new registry, the reference should provide 1079 information about the registry itself, not just a pointer to the 1080 creation of it. Useful information includes the purpose of the 1081 registry, a rationale for its creation, documentation of the 1082 process and policy for new registrations, guidelines for new 1083 registrants or designated experts, and other such related 1084 information. 1086 8. What to Do in "bis" Documents 1088 On occaison, an RFC is issued that obsoletes a previous edition of 1089 the same document. We sometimes call these "bis" documents, such as 1090 when RFC 9876 is updated by draft-ietf-foo-rfc9876bis. When the 1091 original document created registries and/or registered entries, there 1092 is a question of how to handle the IANA Considerations section in the 1093 "bis" document. 1095 If the registrations specify the original document as a reference, 1096 those registrations should be updated to point to the current (not 1097 obsolete) documentation for those items. Usually, that will mean 1098 changing the reference to be the "bis" document. 1100 For example, suppose RFC 9876 registered the "BANANA" flag in the 1101 "Fruit Access Flags" registry, and the documentation for that flag is 1102 in Section 3.2. 1104 The current registry might look, in part, like this: 1106 Name Description Reference 1107 -------- ------------------- --------- 1108 BANANA Flag for bananas [RFC9876], Section 3.2 1110 If draft-ietf-foo-rfc9876bis obsoletes RFC 9876 and, because of some 1111 rearrangement, now documents the flag in Section 4.1.2, the IANA 1112 Considerations of the bis document might contain text such as this: 1114 IANA is asked to change the registration information for the 1115 BANANA flag in the "Fruit Access Flags" registry to the following: 1117 Name Description Reference 1118 -------- ------------------- --------- 1119 BANANA Flag for bananas [[this RFC]], Section 4.2.1 1121 In many cases, if there are a number of registered references to the 1122 original RFC and the document organization has not changed the 1123 registered section numbering much, it may simply be reasonable to do 1124 this: 1126 Because this document obsoletes RFC 9876, IANA is asked to change 1127 all registration information that references [RFC9876] to instead 1128 reference [[this RFC]]. 1130 If information for registered items has been or is being moved to 1131 other documents, then, of course, the registration information should 1132 be changed to point to those other documents. In no case is it 1133 reasonable to leave documentation pointers to the obsoleted document 1134 for any registries or registered items that are still in current use. 1136 9. Miscellaneous Issues 1138 9.1. When There Are No IANA Actions 1140 Before an Internet-Draft can be published as an RFC, IANA needs to 1141 know what actions (if any) it needs to perform. Experience has shown 1142 that it is not always immediately obvious whether a document has no 1143 IANA actions, without reviewing the document in some detail. In 1144 order to make it clear to IANA that it has no actions to perform (and 1145 that the author has consciously made such a determination), such 1146 documents should include an IANA Considerations section that states: 1148 This document has no IANA actions. 1150 This statement, or an equivalent, must only be inserted after the 1151 working group or individual submitter has carefully verified it to be 1152 true. Using such wording as a matter of "boilerplate" or without 1153 careful consideration can lead to incomplete or incorrect IANA 1154 actions being performed. 1156 If a specification makes use of values from a namespace in which 1157 assignments are not made by IANA, it may be useful to note this fact, 1158 with wording such as this: 1160 The values of the Foobar parameter are assigned by the Barfoo 1161 registry on behalf of the Rabfoo Forum. Therefore, this document 1162 has no IANA actions. 1164 In some cases, the absence of IANA-assigned values may be considered 1165 valuable information for future readers; in other cases, it may be 1166 considered of no value once the document has been approved, and may 1167 be removed before archival publication. This choice should be made 1168 clear in the draft, for example, by including a sentence such as 1170 [RFC Editor: please remove this section prior to publication.] 1172 or 1174 [RFC Editor: please do not remove this section.] 1176 9.2. Namespaces Lacking Documented Guidance 1178 For all existing RFCs that either explicitly or implicitly rely on 1179 IANA to make assignments without specifying a precise assignment 1180 policy, IANA (in consultation with the IESG) will continue to decide 1181 what policy is appropriate. Changes to existing policies can always 1182 be initiated through the normal IETF consensus process. 1184 All future RFCs that either explicitly or implicitly rely on IANA to 1185 register or otherwise administer namespace assignments MUST provide 1186 guidelines for administration of the namespace. 1188 9.3. After-the-Fact Registrations 1190 Occasionally, the IETF becomes aware that an unassigned value from a 1191 namespace is in use on the Internet or that an assigned value is 1192 being used for a different purpose than it was registered for. The 1193 IETF does not condone such misuse; procedures of the type described 1194 in this document MUST be applied to such cases. In the absence of 1195 specifications to the contrary, values may only be reassigned for a 1196 different purpose with the consent of the original assignee (when 1197 possible) and with due consideration of the impact of such a 1198 reassignment. In cases of likely controversy, consultation with the 1199 IESG is advised. 1201 9.4. Reclaiming Assigned Values 1203 Reclaiming previously assigned values for reuse is tricky, because 1204 doing so can lead to interoperability problems with deployed systems 1205 still using the assigned values. Moreover, it can be extremely 1206 difficult to determine the extent of deployment of systems making use 1207 of a particular value. However, in cases where the namespace is 1208 running out of unassigned values and additional ones are needed, it 1209 may be desirable to attempt to reclaim unused values. When 1210 reclaiming unused values, the following (at a minimum) should be 1211 considered: 1213 o Attempts should be made to contact the original party to which a 1214 value is assigned, to determine if the value was ever used, and if 1215 so, the extent of deployment. (In some cases, products were never 1216 shipped or have long ceased being used. In other cases, it may be 1217 known that a value was never actually used at all.) 1219 o Reassignments should not normally be made without the concurrence 1220 of the original requester. Reclamation under such conditions 1221 should only take place where there is strong evidence that a value 1222 is not widely used, and the need to reclaim the value outweighs 1223 the cost of a hostile reclamation. In any case, IESG Approval is 1224 needed in this case. 1226 o It may be appropriate to write up the proposed action and solicit 1227 comments from relevant user communities. In some cases, it may be 1228 appropriate to write an RFC that goes through a formal IETF 1229 process (including IETF Last Call) as was done when DHCP reclaimed 1230 some of its "Private Use" options [RFC3942]. 1232 9.5. Contact Person vs Assignee or Owner 1234 Many registries include designation of a technical or administrative 1235 contact associated with each entry. Often, this is recorded as 1236 contact information for an individual. It is unclear, though, what 1237 role the individual has with respect to the registration: is this 1238 item registered on behalf of the individual, the company the 1239 individual worked for, or perhaps another organization the individual 1240 was acting for? 1242 This matters because some time later, when the individual has changed 1243 jobs or roles, and perhaps can no longer be contacted, someone might 1244 want to update the registration. IANA has no way to know what 1245 company, organization, or individual should be allowed to take the 1246 registration over. For registrations rooted in RFCs, the stream 1247 owner (such as the IESG or the IAB) can make an overriding decision. 1248 But in other cases, there is no recourse. 1250 Registries can include, in addition to a "Contact" field, an 1251 "Assignee" or "Owner" field that can be used to address this 1252 situation, giving IANA clear guidance as to the actual owner of the 1253 registration. Alternatively, organizations can put an organizational 1254 role into the "Contact" field in order to make their ownership clear. 1256 9.6. Closing or Obsoleting a Registry 1258 [[This section needs to be resolved before publication.]] 1260 Sometimes there is a request to "close" a registry. Registries can 1261 only be marked as closed, obsoleted or historical through publication 1262 of an RFC. o Closing a registry When closing a registry, no further 1263 registrations will be accepted. The information in the registry will 1264 still be valid and if needed, registrations already in the registry 1265 can be updated. o Making a registry Historical When a registry is 1266 made Historical???? o Obsoleting a registry This means the 1267 information in the registry is no longer used or applicable??? 1268 Whether the registry is closed, obsoleted or made historical, the 1269 information will remain in the registry for informational purposes 1270 unless specifically requested to be removed. all registrations 1271 cancelled and existing values deprecated/ inoperative? values no 1272 longer accessible to public view? 1274 10. Appeals 1276 Appeals of protocol parameter registration decisions can be made 1277 using the normal IETF appeals process as described in [RFC2026], 1278 Section 6.5. That is, an initial appeal should be directed to the 1279 IESG, followed (if necessary) by an appeal to the IAB. 1281 11. Mailing Lists 1283 All IETF mailing lists associated with evaluating or discussing 1284 assignment requests as described in this document are subject to 1285 whatever rules of conduct and methods of list management are 1286 currently defined by Best Current Practices or by IESG decision. 1288 12. Security Considerations 1290 Information that creates or updates a registration needs to be 1291 authenticated and authorized. IANA updates registries according to 1292 instructions in published RFCs and from the IESG. It also may accept 1293 clarifications from document authors, relevant working group chairs, 1294 Designated Experts, and mail list participants, too. 1296 Information concerning possible security vulnerabilities of a 1297 protocol may change over time. Likewise, security vulnerabilities 1298 related to how an assigned number is used may change as well. As new 1299 vulnerabilities are discovered, information about such 1300 vulnerabilities may need to be attached to existing registrations, so 1301 that users are not misled as to the true security issues surrounding 1302 the use of a registered number. 1304 An analysis of security issues is generally required for all 1305 protocols that make use of parameters (data types, operation codes, 1306 keywords, etc.) used in IETF protocols or registered by IANA. Such 1307 security considerations are usually included in the protocol document 1308 [RFC3552]. It is the responsibility of the IANA considerations 1309 associated with a particular registry to specify what (if any) 1310 security considerations must be provided when assigning new values, 1311 and the process for reviewing such claims. 1313 13. To-Do List; resolve and remove before requesting publication 1315 Just was speaking with someone at the IANA office hours. I was 1316 looking through the 5226bis draft and there is nothing in there about 1317 how to deprecate values in registries. Might be something good to 1318 add. 1320 14. Changes Relative to Earlier Editions of BCP 26 1322 14.1. 2013: Changes in This Document Relative to RFC 5226 1324 Significant additions: 1326 o Added Section 5.4, Expert Reviews and the Document Lifecycle 1328 o Moved well-known policies into a separate section for each, 1329 subsections of Section 4. 1331 o Added Section 2.2, Best Practice for Selecting an Appropriate 1332 Policy. 1334 o Added Section 2.2.2, Using Multiple Policies in Combination. 1336 o Added Section 7, Documentation References in IANA Registries 1338 o Added Section 8, What to Do in "bis" Documents 1340 o Added Section 9.5, Contact Person vs Assignee or Owner 1342 o Added Section 9.6, Closing or Obsoleting a Registry 1344 Clarifications and such: 1346 o Some reorganization -- moved text around for clarity and easier 1347 reading. 1349 o Made clarifications about identification of IANA registries and 1350 use of URLs for them. 1352 o Clarified the distinction between "Unassigned" and "Reserved". 1354 o Made some clarifications in "Expert Review" about instructions to 1355 the designated expert. 1357 o Made some clarifications in "Specification Required" about how to 1358 declare this policy. 1360 o Assorted minor clarifications and editorial changes throughout. 1362 14.2. 2008: Changes in RFC 5226 Relative to RFC 2434 1364 Changes include: 1366 o Major reordering of text to expand descriptions and to better 1367 group topics such as "updating registries" vs. "creating new 1368 registries", in order to make it easier for authors to find the 1369 text most applicable to their needs. 1371 o Numerous editorial changes to improve readability. 1373 o Changed the term "IETF Consensus" to "IETF Review" and added more 1374 clarifications. History has shown that people see the words "IETF 1375 Consensus" (without consulting the actual definition) and are 1376 quick to make incorrect assumptions about what the term means in 1377 the context of IANA Considerations. 1379 o Added "RFC Required" to list of defined policies. 1381 o Much more explicit directions and examples of "what to put in 1382 RFCs". 1384 o "Specification Required" now implies use of a Designated Expert to 1385 evaluate specs for sufficient clarity. 1387 o Significantly changed the wording in the Designated Experts 1388 section. Main purpose is to make clear that Expert Reviewers are 1389 accountable to the community, and to provide some guidance for 1390 review criteria in the default case. 1392 o Changed wording to remove any special appeals path. The normal 1393 RFC 2026 appeals path is used. 1395 o Added a section about reclaiming unused value. 1397 o Added a section on after-the-fact registrations. 1399 o Added a section indicating that mailing lists used to evaluate 1400 possible assignments (such as by a Designated Expert) are subject 1401 to normal IETF rules. 1403 15. Acknowledgments 1405 15.1. Acknowledgments for This Document (2013) 1406 Thomas Narten and Harald Tveit Alvestrand edited the two earlier 1407 editions of this document (RFCs 2434 and 5226), and Thomas continues 1408 his role in this third edition. Much of the text from RFC 5226 1409 remains in this edition. 1411 This document has benefited from thorough review and comments by John 1412 Klensin and Mark Nottingham. 1414 Special thanks to Mark Nottingham for reorganizing some of the text 1415 for better organization and readability. 1417 15.2. Acknowledgments from the second edition (2008) 1419 The original acknowledgments section in RFC 5226 was: 1421 This document has benefited from specific feedback from Jari Arkko, 1422 Marcelo Bagnulo Braun, Brian Carpenter, Michelle Cotton, Spencer 1423 Dawkins, Barbara Denny, Miguel Garcia, Paul Hoffman, Russ Housley, 1424 John Klensin, Allison Mankin, Blake Ramsdell, Mark Townsley, Magnus 1425 Westerlund, and Bert Wijnen. 1427 15.3. Acknowledgments from the first edition (1998) 1429 The original acknowledgments section in RFC 2434 was: 1431 Jon Postel and Joyce Reynolds provided a detailed explanation on what 1432 IANA needs in order to manage assignments efficiently, and patiently 1433 provided comments on multiple versions of this document. Brian 1434 Carpenter provided helpful comments on earlier versions of the 1435 document. One paragraph in the Security Considerations section was 1436 borrowed from [RFC4288]. 1438 16. References 1440 16.1. Normative References 1442 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 1443 Requirement Levels", BCP 14, RFC 2119, March 1997. 1445 16.2. Informative References 1447 [RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791, September 1448 1981. 1450 [RFC2026] Bradner, S., "The Internet Standards Process -- Revision 1451 3", BCP 9, RFC 2026, October 1996. 1453 [RFC2132] Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor 1454 Extensions", RFC 2132, March 1997. 1456 [RFC2860] Carpenter, B., Baker, F. and M. Roberts, "Memorandum of 1457 Understanding Concerning the Technical Work of the 1458 Internet Assigned Numbers Authority", RFC 2860, June 2000. 1460 [RFC2929] Eastlake, D., Brunner-Williams, E. and B. Manning, "Domain 1461 Name System (DNS) IANA Considerations", RFC 2929, 1462 September 2000. 1464 [RFC2939] Droms, R., "Procedures and IANA Guidelines for Definition 1465 of New DHCP Options and Message Types", BCP 43, RFC 2939, 1466 September 2000. 1468 [RFC3228] Fenner, B., "IANA Considerations for IPv4 Internet Group 1469 Management Protocol (IGMP)", BCP 57, RFC 3228, February 1470 2002. 1472 [RFC3232] Reynolds, J., "Assigned Numbers: RFC 1700 is Replaced by 1473 an On-line Database", RFC 3232, January 2002. 1475 [RFC3552] Rescorla, E. and B. Korver, "Guidelines for Writing RFC 1476 Text on Security Considerations", BCP 72, RFC 3552, July 1477 2003. 1479 [RFC3575] Aboba, B., "IANA Considerations for RADIUS (Remote 1480 Authentication Dial In User Service)", RFC 3575, July 1481 2003. 1483 [RFC3692] Narten, T., "Assigning Experimental and Testing Numbers 1484 Considered Useful", BCP 82, RFC 3692, January 2004. 1486 [RFC3748] Aboba, B., Blunk, L., Vollbrecht, J., Carlson, J. and H. 1487 Levkowetz, "Extensible Authentication Protocol (EAP)", RFC 1488 3748, June 2004. 1490 [RFC3942] Volz, B., "Reclassifying Dynamic Host Configuration 1491 Protocol version 4 (DHCPv4) Options", RFC 3942, November 1492 2004. 1494 [RFC3968] Camarillo, G., "The Internet Assigned Number Authority 1495 (IANA) Header Field Parameter Registry for the Session 1496 Initiation Protocol (SIP)", BCP 98, RFC 3968, December 1497 2004. 1499 [RFC4005] Calhoun, P., Zorn, G., Spence, D. and D. Mitton, "Diameter 1500 Network Access Server Application", RFC 4005, August 2005. 1502 [RFC4025] Richardson, M., "A Method for Storing IPsec Keying 1503 Material in DNS", RFC 4025, March 2005. 1505 [RFC4044] McCloghrie, K., "Fibre Channel Management MIB", RFC 4044, 1506 May 2005. 1508 [RFC4124] Le Faucheur, F., "Protocol Extensions for Support of 1509 Diffserv-aware MPLS Traffic Engineering", RFC 4124, June 1510 2005. 1512 [RFC4169] Torvinen, V., Arkko, J. and M. Naslund, "Hypertext 1513 Transfer Protocol (HTTP) Digest Authentication Using 1514 Authentication and Key Agreement (AKA) Version-2", RFC 1515 4169, November 2005. 1517 [RFC4271] Rekhter, Y., Li, T. and S. Hares, "A Border Gateway 1518 Protocol 4 (BGP-4)", RFC 4271, January 2006. 1520 [RFC4283] Patel, A., Leung, K., Khalil, M., Akhtar, H. and K. 1521 Chowdhury, "Mobile Node Identifier Option for Mobile IPv6 1522 (MIPv6)", RFC 4283, November 2005. 1524 [RFC4288] Freed, N. and J. Klensin, "Media Type Specifications and 1525 Registration Procedures", BCP 13, RFC 4288, December 2005. 1527 [RFC4301] Kent, S. and K. Seo, "Security Architecture for the 1528 Internet Protocol", RFC 4301, December 2005. 1530 [RFC4340] Kohler, E., Handley, M. and S. Floyd, "Datagram Congestion 1531 Control Protocol (DCCP)", RFC 4340, March 2006. 1533 [RFC4395] Hansen, T., Hardie, T. and L. Masinter, "Guidelines and 1534 Registration Procedures for New URI Schemes", BCP 35, RFC 1535 4395, February 2006. 1537 [RFC4422] Melnikov, A. and K. Zeilenga, "Simple Authentication and 1538 Security Layer (SASL)", RFC 4422, June 2006. 1540 [RFC4446] Martini, L., "IANA Allocations for Pseudowire Edge to Edge 1541 Emulation (PWE3)", BCP 116, RFC 4446, April 2006. 1543 [RFC4520] Zeilenga, K., "Internet Assigned Numbers Authority (IANA) 1544 Considerations for the Lightweight Directory Access 1545 Protocol (LDAP)", BCP 64, RFC 4520, June 2006. 1547 [RFC4589] Schulzrinne, H. and H. Tschofenig, "Location Types 1548 Registry", RFC 4589, July 2006. 1550 [RFC4727] Fenner, B., "Experimental Values In IPv4, IPv6, ICMPv4, 1551 ICMPv6, UDP, and TCP Headers", RFC 4727, November 2006. 1553 [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security 1554 (TLS) Protocol Version 1.2", RFC 5246, August 2008. 1556 [RFC5378] Bradner, S. and J. Contreras, "Rights Contributors Provide 1557 to the IETF Trust", BCP 78, RFC 5378, November 2008. 1559 [RFC5742] Alvestrand, H. and R. Housley, "IESG Procedures for 1560 Handling of Independent and IRTF Stream Submissions", BCP 1561 92, RFC 5742, December 2009. 1563 [RFC5771] Cotton, M., Vegoda, L. and D. Meyer, "IANA Guidelines for 1564 IPv4 Multicast Address Assignments", BCP 51, RFC 5771, 1565 March 2010. 1567 [RFC5795] Sandlund, K., Pelletier, G. and L-E. Jonsson, "The RObust 1568 Header Compression (ROHC) Framework", RFC 5795, March 1569 2010. 1571 [RFC6195] Eastlake, D., "Domain Name System (DNS) IANA 1572 Considerations", BCP 42, RFC 6195, March 2011. 1574 [RFC6275] Perkins, C., Johnson, D. and J. Arkko, "Mobility Support 1575 in IPv6", RFC 6275, July 2011. 1577 [RFC6709] Carpenter, B., Aboba, B. and S. Cheshire, "Design 1578 Considerations for Protocol Extensions", RFC 6709, 1579 September 2012. 1581 Authors' Addresses 1583 Michelle Cotton 1584 Internet Corporation for Assigned Names and Numbers 1585 12025 Waterfront Drive, Suite 300 1586 Los Angeles, CA 90094-2536 1587 US 1589 Phone: +1 310 823 9358 1590 Email: michelle.cotton@icann.org 1591 URI: http://www.icann.org/ 1593 Barry Leiba 1594 Huawei Technologies 1596 Phone: +1 646 827 0648 1597 Email: barryleiba@computer.org 1598 URI: http://internetmessagingtechnology.org/ 1600 Thomas Narten 1601 IBM Corporation 1602 3039 Cornwallis Ave., PO Box 12195 - BRQA/502 1603 Research Triangle Park, NC 27709-2195 1604 US 1606 Phone: +1 919 254 7798 1607 Email: narten@us.ibm.com