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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group N. Freed 3 Internet-Draft Oracle 4 Obsoletes: 4288 (if approved) J. Klensin 5 Expires: August 7, 2012 6 T. Hansen 7 AT&T Laboratories 8 February 4, 2012 10 Media Type Specifications and Registration Procedures 11 draft-ietf-appsawg-media-type-regs-01 13 Abstract 15 This document defines procedures for the specification and 16 registration of media types for use in HTTP, MIME and other Internet 17 protocols. 19 Status of this Memo 21 This Internet-Draft is submitted in full conformance with the 22 provisions of BCP 78 and BCP 79. 24 Internet-Drafts are working documents of the Internet Engineering 25 Task Force (IETF). Note that other groups may also distribute 26 working documents as Internet-Drafts. The list of current Internet- 27 Drafts is at http://datatracker.ietf.org/drafts/current/. 29 Internet-Drafts are draft documents valid for a maximum of six months 30 and may be updated, replaced, or obsoleted by other documents at any 31 time. It is inappropriate to use Internet-Drafts as reference 32 material or to cite them other than as "work in progress." 34 This Internet-Draft will expire on August 7, 2012. 36 Copyright Notice 38 Copyright (c) 2012 IETF Trust and the persons identified as the 39 document authors. All rights reserved. 41 This document is subject to BCP 78 and the IETF Trust's Legal 42 Provisions Relating to IETF Documents 43 (http://trustee.ietf.org/license-info) in effect on the date of 44 publication of this document. Please review these documents 45 carefully, as they describe your rights and restrictions with respect 46 to this document. Code Components extracted from this document must 47 include Simplified BSD License text as described in Section 4.e of 48 the Trust Legal Provisions and are provided without warranty as 49 described in the Simplified BSD License. 51 Table of Contents 53 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 54 1.1. Historical Note . . . . . . . . . . . . . . . . . . . . . 4 55 1.2. Conventions Used in This Document . . . . . . . . . . . . 4 56 2. Media Type Registration Preliminaries . . . . . . . . . . . . 5 57 3. Registration Trees and Subtype Names . . . . . . . . . . . . . 5 58 3.1. Standards Tree . . . . . . . . . . . . . . . . . . . . . . 5 59 3.2. Vendor Tree . . . . . . . . . . . . . . . . . . . . . . . 6 60 3.3. Personal or Vanity Tree . . . . . . . . . . . . . . . . . 7 61 3.4. Special x. Tree . . . . . . . . . . . . . . . . . . . . . 7 62 3.5. Additional Registration Trees . . . . . . . . . . . . . . 8 63 4. Registration Requirements . . . . . . . . . . . . . . . . . . 8 64 4.1. Functionality Requirement . . . . . . . . . . . . . . . . 8 65 4.2. Naming Requirements . . . . . . . . . . . . . . . . . . . 8 66 4.2.1. Text Media Types . . . . . . . . . . . . . . . . . . . 9 67 4.2.2. Image Media Types . . . . . . . . . . . . . . . . . . 10 68 4.2.3. Audio Media Types . . . . . . . . . . . . . . . . . . 10 69 4.2.4. Video Media Types . . . . . . . . . . . . . . . . . . 10 70 4.2.5. Application Media Types . . . . . . . . . . . . . . . 11 71 4.2.6. Multipart and Message Media Types . . . . . . . . . . 11 72 4.2.7. Additional Top-level Types . . . . . . . . . . . . . . 12 73 4.2.8. Structured Syntax Name Suffixes . . . . . . . . . . . 12 74 4.2.9. Deprecated Aliases . . . . . . . . . . . . . . . . . . 12 75 4.3. Parameter Requirements . . . . . . . . . . . . . . . . . . 13 76 4.4. Canonicalization and Format Requirements . . . . . . . . . 13 77 4.5. Interchange Recommendations . . . . . . . . . . . . . . . 14 78 4.6. Security Requirements . . . . . . . . . . . . . . . . . . 15 79 4.7. Requirements specific to XML media types . . . . . . . . . 16 80 4.8. Encoding Requirements . . . . . . . . . . . . . . . . . . 16 81 4.9. Usage and Implementation Non-requirements . . . . . . . . 17 82 4.10. Publication Requirements . . . . . . . . . . . . . . . . . 17 83 4.11. Additional Information . . . . . . . . . . . . . . . . . . 18 84 5. Media Type Registration Procedures . . . . . . . . . . . . . . 18 85 5.1. Preliminary Community Review . . . . . . . . . . . . . . . 19 86 5.2. Submit request to IANA . . . . . . . . . . . . . . . . . . 19 87 5.2.1. Provisional Registrations . . . . . . . . . . . . . . 19 88 5.3. Review and Approval . . . . . . . . . . . . . . . . . . . 20 89 5.4. Comments on Media Type Registrations . . . . . . . . . . . 20 90 5.5. Location of Registered Media Type List . . . . . . . . . . 20 91 5.6. Change Procedures . . . . . . . . . . . . . . . . . . . . 21 92 5.7. Registration Template . . . . . . . . . . . . . . . . . . 22 93 6. Structured Syntax Suffix Registration Procedures . . . . . . . 23 94 6.1. Change Procedures . . . . . . . . . . . . . . . . . . . . 24 95 6.2. Structured Syntax Suffix Registration Template . . . . . . 24 97 7. Security Considerations . . . . . . . . . . . . . . . . . . . 25 98 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25 99 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 25 100 10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 26 101 10.1. Normative References . . . . . . . . . . . . . . . . . . . 26 102 10.2. Informative References . . . . . . . . . . . . . . . . . . 27 103 Appendix A. Grandfathered Media Types . . . . . . . . . . . . . . 27 104 Appendix B. Open Issues . . . . . . . . . . . . . . . . . . . . . 28 105 Appendix C. Changes Since RFC 4288 . . . . . . . . . . . . . . . 28 106 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 29 108 1. Introduction 110 Recent Internet protocols have been carefully designed to be easily 111 extensible in certain areas. In particular, many protocols, 112 including but not limited to HTTP [RFC2616] and MIME [RFC2045], are 113 capable of carrying arbitrary labeled content. A mechanism is needed 114 to label such content and a registration process is needed for these 115 labels, so that that the set of such values are defined in a 116 reasonably orderly, well-specified, and public manner. 118 This document defines media type specification and registration 119 procedures that use the Internet Assigned Numbers Authority (IANA) as 120 a central registry. 122 1.1. Historical Note 124 The media type registration process was initially defined for 125 registering media types for use in the context of the asynchronous 126 Internet mail environment. In this mail environment there is a need 127 to limit the number of possible media types, to increase the 128 likelihood of interoperability when the capabilities of the remote 129 mail system are not known. As media types are used in new 130 environments in which the proliferation of media types is not a 131 hindrance to interoperability, the original procedure proved 132 excessively restrictive and had to be generalized. This was 133 initially done in [RFC2048], but the procedure defined there was 134 still part of the MIME document set. The media type specification 135 and registration procedure has now been moved to this separate 136 document, to make it clear that it is independent of MIME. 138 It may be desirable to restrict the use of media types to specific 139 environments or to prohibit their use in other environments. This 140 revision incorporates such restrictions into media type registrations 141 in a systematic way. See Section 4.9 for additional discussion. 143 1.2. Conventions Used in This Document 145 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 146 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 147 document are to be interpreted as described in [RFC2119]. 149 This specification makes use of the Augmented Backus-Naur Form (ABNF) 150 [RFC5234] notation, including the core rules defined in Appendix A of 151 that document. 153 2. Media Type Registration Preliminaries 155 Registration of a new media type or types starts with the 156 construction of a registration proposal. Registration may occur 157 within several different registration trees that have different 158 requirements, as discussed below. In general, a new registration 159 proposal is circulated and reviewed in a fashion appropriate to the 160 tree involved. The media type is then registered if the proposal is 161 acceptable. The following sections describe the requirements and 162 procedures used for each of the different registration trees. 164 3. Registration Trees and Subtype Names 166 In order to increase the efficiency and flexibility of the 167 registration process, different structures of subtype names may be 168 registered to accommodate the different natural requirements for, 169 e.g., a subtype that will be recommended for wide support and 170 implementation by the Internet community, or a subtype that is used 171 to move files associated with proprietary software. The following 172 subsections define registration "trees" that are distinguished by the 173 use of faceted names, e.g., names of the form 174 "tree.subtree...subtype". Note that some media types defined prior 175 to this document do not conform to the naming conventions described 176 below. See Appendix A for a discussion of them. 178 3.1. Standards Tree 180 The standards tree is intended for types of general interest to the 181 Internet community. Registrations in the standards tree MUST be 182 either: 184 1. in the case of registrations in IETF specifications, approved 185 directly by the IESG, or 187 2. registered by a recognized standards body using the 188 "Specification Required" IANA registration policy [RFC5226] 189 (which implies Expert Review). 191 The first procedure is used for registering registrations from IETF 192 Consensus documents, or in rare cases when registering a 193 grandfathered (see Appendix A) and/or otherwise incomplete 194 registration is in the interest of the Internet community. 196 In the second case the IESG makes the decision on whether the 197 registration submitter represents a recognized standards body; after 198 that, a Media Types Reviewer (Designated Expert or a group of 199 Designated Experts) performs the Expert Review as specified in this 200 document. 202 In the case of registration for the IETF itself, the registration 203 proposal MUST be published as an IETF Consensus RFC, which can be on 204 the Standards Track, a BCP, Informational, or Experimental. In the 205 case of registrations for other recognized standards bodies, the 206 format MUST be described by a formal standards specification produced 207 by that body. 209 Registrations published in non-IETF RFC streams are allowed and 210 require IESG approval. 212 Standards-tree registration RFCs can either be standalone 213 "registration only" RFCs, or they can be incorporated into a more 214 general specification of some sort. 216 Media types in the standards tree are normally denoted by names that 217 are not explicitly faceted, i.e., do not contain period (".", full 218 stop) characters. 220 The "owner" of a media type registration in the standards tree is 221 assumed to be the standards body itself. Modification or alteration 222 of the specification uses the same level of processing (e.g., a 223 registration submitted on Standards Track can be revised in another 224 Standards Track RFC, but cannot be revised in an Informational RFC) 225 required for the initial registration. 227 Standards-tree registrations from recognized standards bodies may be 228 submitted directly to the IANA, where they will undergo Expert Review 229 [RFC5226] prior to approval. In this case, the Expert Reviewer(s) 230 will, among other things, ensure that the required specification 231 provides adequate documentation. 233 3.2. Vendor Tree 235 The vendor tree is used for media types associated with commercially 236 available products. "Vendor" and "producer" are construed very 237 broadly in this context and are considered equivalent. Note that 238 industry consortia and similar groups that do not qualify as 239 recognized standards bodies can quite appropriately register media 240 types in the vendor tree. 242 A registration may be placed in the vendor tree by anyone who needs 243 to interchange files associated with some product or set of products. 244 However, the registration formally belongs to the vendor or 245 organization producing the software or file format being registered. 246 Changes to the specification will be made at their request, as 247 discussed in subsequent sections. 249 Registrations in the vendor tree will be distinguished by the leading 250 facet "vnd.". That may be followed, at the discretion of the 251 registrant, by either a media subtype name from a well-known producer 252 (e.g., "vnd.mudpie") or by an IANA-approved designation of the 253 producer's name that is followed by a media type or product 254 designation (e.g., vnd.bigcompany.funnypictures). 256 While public exposure and review of media types to be registered in 257 the vendor tree is not required, using the ietf-types@iana.org 258 mailing list for review is encouraged to improve the quality of those 259 specifications. Registrations in the vendor tree may be submitted 260 directly to the IANA, where they will undergo Expert Review [RFC5226] 261 prior to approval. 263 3.3. Personal or Vanity Tree 265 Registrations for media types created experimentally or as part of 266 products that are not distributed commercially may be registered in 267 the personal or vanity tree. The registrations are distinguished by 268 the leading facet "prs.". 270 The owner of "personal" registrations and associated specifications 271 is the person or entity making the registration, or one to whom 272 responsibility has been transferred as described below. 274 While public exposure and review of media types to be registered in 275 the personal tree is not required, using the ietf-types@iana.org 276 mailing list (see Section 5.1) for review is encouraged to improve 277 the quality of those specifications. Registrations in the personal 278 tree may be submitted directly to the IANA, where they will undergo 279 Expert Review [RFC5226] prior to approval. 281 3.4. Special x. Tree 283 For convenience and symmetry with this registration scheme, subtype 284 names with "x." as the first facet may be used for the same purposes 285 for which names starting in "x-" are used. These types are 286 unregistered, experimental, and for use only with the active 287 agreement of the parties exchanging them. 289 However, with the simplified registration procedures described above 290 for vendor and personal trees, it should rarely, if ever, be 291 necessary to use unregistered experimental types. Therefore, use of 292 both "x-" and "x." forms is strongly discouraged. 294 Types in this tree MUST NOT be registered. If a generally useful and 295 widely deployed type incorrectly ends up with an "x." or "x-" name 296 prefix, it MAY be registered using its current name in an alternate 297 tree by following the procedure defined in Appendix A. 299 3.5. Additional Registration Trees 301 From time to time and as required by the community, new top-level 302 registration trees may be created by IETF Standards Action. It is 303 explicitly assumed that these trees may be created for external 304 registration and management by well-known permanent bodies; for 305 example, scientific societies may register media types specific to 306 the sciences they cover. In general, the quality of review of 307 specifications for one of these additional registration trees is 308 expected to be equivalent to registrations in the standards tree by a 309 recognized Standards Development Organization. When the IETF 310 performs such review, it needs to consider the greater expertise of 311 the requesting body with respect to the subject media type. 313 4. Registration Requirements 315 Media type registrations are all expected to conform to various 316 requirements laid out in the following sections. Note that 317 requirement specifics sometimes vary depending on the registration 318 tree, again as detailed in the following sections. 320 4.1. Functionality Requirement 322 Media types MUST function as an actual media format. Registration of 323 things that are better thought of as a transfer encoding, as a 324 charset, or as a collection of separate entities of another type, is 325 not allowed. For example, although applications exist to decode the 326 base64 transfer encoding [RFC2045], base64 cannot be registered as a 327 media type. 329 This requirement applies regardless of the registration tree 330 involved. 332 4.2. Naming Requirements 334 All registered media types MUST be assigned type and subtype names. 335 The combination of these names serves to uniquely identify the media 336 type, and the format of the subtype name identifies the registration 337 tree. Both type and subtype names are case-insensitive. 339 Type and subtype names beginning with "x-" are reserved for 340 experimental use and MUST NOT be registered. This parallels the 341 restriction on the x. tree, as discussed in Section 3.4. 343 Type and subtype names MUST conform to the following ABNF: 345 type-name = restricted-name 346 subtype-name = restricted-name 348 restricted-name = 1*127restricted-name-chars 349 restricted-name-chars = ALPHA / DIGIT / "!" / 350 "#" / "$" / "&" / "." / 351 "+" / "-" / "^" / "_" 353 Note that this syntax is somewhat more restrictive than what is 354 allowed by the ABNF in section 5.1 of [RFC2045]. Also note that 355 while this syntax allows names of up to 127 characters, 356 implementation limits may make such long names problematic. For this 357 reason the components of names SHOULD be limited to 64 characters. 359 Although the name syntax treates "+" as equivalent to any other 360 character, it is used in media type names to introduce a structured 361 syntax specificer suffix. Structured syntax suffix requirements are 362 specified in Section 4.2.8. 364 While it is possible for a given media type to be assigned additional 365 names, the use of different names to identify the same media type is 366 discouraged. 368 These requirements apply regardless of the registration tree 369 involved. 371 The choice of top-level type name MUST take into account the nature 372 of media type involved. New subtypes of top-level types MUST conform 373 to the restrictions of the top-level type, if any. The following 374 sections describe each of the initial set of top-level types and 375 their associated restrictions. Additionally, various protocols, 376 including but not limited to HTTP and MIME, MAY impose additional 377 restrictions on the media types they can transport. (See [RFC2046] 378 for additional information on the restrictions MIME imposes.) 380 4.2.1. Text Media Types 382 The "text" media type is intended for sending material that is 383 principally textual in form. 385 Many subtypes of text, notably including the subtype "text/plain", 386 which is a generic subtype for plain text defined in [RFC2046], 387 define a "charset" parameter. If a "charset" parameter is defined 388 for a particular subtype of text, it MUST be used to specify a 389 charset name defined in accordance to the procedures laid out in 390 [RFC2978]. 392 A "charset" parameter SHOULD NOT be specified when charset 393 information is transported inside the payload (e.g., as in "text/ 394 xml"). 396 If a "charset" parameter is specified, it SHOULD be a required 397 parameter, eliminating the options of specifying a default value. If 398 there is a strong reason for the parameter to be optional despite 399 this advice, each subtype MAY specify its own default value, or 400 alternately, it MAY specify that there is no default value. Finally, 401 the "UTF-8" charset [RFC3629] SHOULD be selected as the default. See 402 [I-D.ietf-appsawg-mime-default-charset] for additional information on 403 the use of "charset" parameters in conjunction with subtypes of text. 405 Plain text does not provide for or allow formatting commands, font 406 attribute specifications, processing instructions, interpretation 407 directives, or content markup. Plain text is seen simply as a linear 408 sequence of characters, possibly interrupted by line breaks or page 409 breaks. Plain text MAY allow the stacking of several characters in 410 the same position in the text. Plain text in scripts like Arabic and 411 Hebrew may also include facilities that allow the arbitrary mixing of 412 text segments with different writing directions. 414 Beyond plain text, there are many formats for representing what might 415 be known as "rich text". An interesting characteristic of many such 416 representations is that they are to some extent readable even without 417 the software that interprets them. It is useful to distinguish them, 418 at the highest level, from such unreadable data as images, audio, or 419 text represented in an unreadable form. In the absence of 420 appropriate interpretation software, it is reasonable to present 421 subtypes of "text" to the user, while it is not reasonable to do so 422 with most non-textual data. Such formatted textual data should be 423 represented using subtypes of "text". 425 4.2.2. Image Media Types 427 A media type of "image" indicates that the content specifies one or 428 more individual images. The subtype names the specific image format. 430 4.2.3. Audio Media Types 432 A media type of "audio" indicates that the content contains audio 433 data. 435 4.2.4. Video Media Types 437 A media type of "video" indicates that the content specifies a time- 438 varying-picture image, possibly with color and coordinated sound. 439 The term 'video' is used in its most generic sense, rather than with 440 reference to any particular technology or format, and is not meant to 441 preclude subtypes such as animated drawings encoded compactly. 443 Note that although in general this document strongly discourages the 444 mixing of multiple media in a single body, it is recognized that many 445 so-called video formats include a representation for synchronized 446 audio and/or text, and this is explicitly permitted for subtypes of 447 "video". 449 4.2.5. Application Media Types 451 The "application" media type is to be used for discrete data that do 452 not fit in any of the media types, and particularly for data to be 453 processed by some type of application program. This is information 454 that must be processed by an application before it is viewable or 455 usable by a user. Expected uses for the "application" media type 456 include but are not limited to file transfer, spreadsheets, 457 presentations, scheduling data, and languages for "active" 458 (computational) material. (The last, in particular, can pose 459 security problems that must be understood by implementors, and that 460 are considered in detail in the discussion of the "application/ 461 postscript" media type in [RFC2046].) 463 For example, a meeting scheduler might define a standard 464 representation for information about proposed meeting dates. An 465 intelligent user agent would use this information to conduct a dialog 466 with the user, and might then send additional material based on that 467 dialog. More generally, there have been several "active" languages 468 developed in which programs in a suitably specialized language are 469 transported to a remote location and automatically run in the 470 recipient's environment. Such applications may be defined as 471 subtypes of the "application" media type. 473 The subtype of "application" will often either be the name or include 474 part of the name of the application for which the data are intended. 475 This does not mean, however, that any application program name may 476 simply be used freely as a subtype of "application"; the subtype 477 needs to be registered. 479 4.2.6. Multipart and Message Media Types 481 Multipart and message are composite types, that is, they provide a 482 means of encapsulating zero or more objects, each labeled with its 483 own media type. 485 All subtypes of multipart and message MUST conform to the syntax 486 rules and other requirements specified in [RFC2046] and amended by 487 Section 3.5 of [RFC6532]. 489 4.2.7. Additional Top-level Types 491 In some cases a new media type may not "fit" under any currently 492 defined top-level content type. Such cases are expected to be quite 493 rare. However, if such a case does arise a new top-level type can be 494 defined to accommodate it. Such a definition MUST be done via 495 standards-track RFC; no other mechanism can be used to define 496 additional top-level content types. 498 4.2.8. Structured Syntax Name Suffixes 500 [RFC3023] defined the first such augmentation to the media type 501 definition to additionally specify the underlying structure of that 502 media type. To quote: 504 This document also standardizes a convention (using the suffix 505 '+xml') for naming media types ... when those media types 506 represent XML MIME (Multipurpose Internet Mail Extensions) 507 entities. 509 That is, it specified a suffix (in that case, "+xml") to be appended 510 to the base media type name. 512 Since this was published, the defacto practice has arisen for using 513 this suffix convention for other well-known structuring syntaxes. In 514 particular, media types have been registered with suffixes such as 515 "+der", "+fastinfoset" and "+json". This specification formalizes 516 this practice and sets up a registry for structured type name 517 suffixes. 519 The primary guideline for whether a structured type name suffix 520 should be registerable is that it be described by a readily-available 521 description, preferably within a document published by an established 522 standards organization, and for which there's a reference that can be 523 used in a References section of an RFC. 525 Media types that make use of a named structured syntax SHOULD use the 526 appropriate registered "+suffix" for that structured syntax when they 527 are registered. By the same token, media types MUST NOT be given 528 names incorporating suffixes for structured syntaxes they do not 529 actually employ. "+suffix" constructs for as-yet unregistered 530 structured syntaxes should be used with care, given the possibility 531 of conflicts with future suffix definitions. 533 4.2.9. Deprecated Aliases 535 In some cases a single media type may have been widely deployed prior 536 to registrion under multiple names. In such cases a preferred name 537 MUST be chosen for the media type and applications MUST use this to 538 be compliant with the type's registration. However, a list of 539 deprecated aliases the type is known by MAY be supplied as additional 540 information in order to assist application in processing the media 541 type properly. 543 4.3. Parameter Requirements 545 Media types MAY elect to use one or more media type parameters, or 546 some parameters may be automatically made available to the media type 547 by virtue of being a subtype of a content type that defines a set of 548 parameters applicable to any of its subtypes. In either case, the 549 names, values, and meanings of any parameters MUST be fully specified 550 when a media type is registered in the standards tree, and SHOULD be 551 specified as completely as possible when media types are registered 552 in the vendor or personal trees. 554 Parameter names have the syntax as media type names and values: 556 parameter-name = restricted-name 558 Note that this syntax is somewhat more restrictive than what is 559 allowed by the ABNF in [RFC2045] and amended by [RFC2231]. 561 Parameter names are case-insensitive and no meaning is attached to 562 the order in which they appear. It is an error for a specific 563 parameter to be specified more than once. 565 There is no defined syntax for parameter values. Therefore 566 registrations MUST specify parameter value syntax. Additionally, 567 some transports impose restrictions on parameter value syntax, so 568 care should be taken to limit the use of potentially problematic 569 syntaxes; e.g., pure binary valued parameters, while permitted in 570 some protocols, probably should be avoided. 572 New parameters SHOULD NOT be defined as a way to introduce new 573 functionality in types registered in the standards tree, although new 574 parameters MAY be added to convey additional information that does 575 not otherwise change existing functionality. An example of this 576 would be a "revision" parameter to indicate a revision level of an 577 external specification such as JPEG. Similar behavior is encouraged 578 for media types registered in the vendor or personal trees, but is 579 not required. 581 4.4. Canonicalization and Format Requirements 583 All registered media types MUST employ a single, canonical data 584 format, regardless of registration tree. 586 A precise and openly available specification of the format of each 587 media type MUST exist for all types registered in the standards tree 588 and MUST at a minimum be referenced by, if it is not actually 589 included in, the media type registration proposal itself. 591 The specifications of format and processing particulars may or may 592 not be publicly available for media types registered in the vendor 593 and personal trees, and such registrations are explicitly permitted 594 to limit the information in the registration to which software and 595 version produce or process such media types. References to or 596 inclusion of format specifications in registrations is encouraged but 597 not required. Note, however, that the public availability of a 598 meaningful specification will often make the difference between 599 simply having a name reserved so that there are no conflicts with 600 other uses and having the potential for other implementations of the 601 media type and useful interoperation with them. 603 Some media types involve the use of patented technology. The 604 registration of media types involving patented technology is 605 specifically permitted. However, the restrictions set forth in 606 [RFC3979] and [RFC5378] on the use of patented technology in IETF 607 standards-track protocols must be respected when the specification of 608 a media type is part of a standards-track protocol. In addition, 609 other standards bodies making use of the standards tree may have 610 their own rules regarding intellectual property that must be observed 611 in their registrations. 613 IPR disclosures for registrations in the vendor and personal tree are 614 encouraged but not required. 616 4.5. Interchange Recommendations 618 Media types SHOULD interoperate across as many systems and 619 applications as possible. However, some media types will inevitably 620 have problems interoperating across different platforms. Problems 621 with different versions, byte ordering, and specifics of gateway 622 handling can and will arise. 624 Universal interoperability of media types is not required, but known 625 interoperability issues SHOULD be identified whenever possible. 626 Publication of a media type does not require an exhaustive review of 627 interoperability, and the interoperability considerations section is 628 subject to continuing evaluation. 630 These recommendations in this subsection apply regardless of the 631 registration tree involved. 633 4.6. Security Requirements 635 An analysis of security issues MUST be done for all types registered 636 in the standards Tree. A similar analysis for media types registered 637 in the vendor or personal trees is encouraged but not required. 638 However, regardless of what security analysis has or has not been 639 done, all descriptions of security issues MUST be as accurate as 640 possible regardless of registration tree. In particular, a statement 641 that there are "no security issues associated with this type" MUST 642 NOT be confused with "the security issues associates with this type 643 have not been assessed". 645 There is absolutely no requirement that media types registered in any 646 tree be secure or completely free from risks. Nevertheless, all 647 known security risks MUST be identified in the registration of a 648 media type, again regardless of registration tree. 650 The security considerations section of all registrations is subject 651 to continuing evaluation and modification, and in particular MAY be 652 extended by use of the "comments on media types" mechanism described 653 in Section 5.4 below. 655 Some of the issues that should be examined and described in a 656 security analysis of a media type are: 658 o Complex media types may include provisions for directives that 659 institute actions on a recipient's files or other resources. In 660 many cases provision is made for originators to specify arbitrary 661 actions in an unrestricted fashion that may then have devastating 662 effects. See the registration of the application/postscript media 663 type in [RFC2046] for an example of such directives and how they 664 should be described in a media type registration. 666 o All registrations MUST state whether or not they employ such 667 "active content", and if they do, they MUST state what steps have 668 been taken to protect users of the media type from harm. 670 o Complex media types may include provisions for directives that 671 institute actions that, while not directly harmful to the 672 recipient, may result in disclosure of information that either 673 facilitates a subsequent attack or else violates a recipient's 674 privacy in some way. Again, the registration of the application/ 675 postscript media type illustrates how such directives can be 676 handled. 678 o A media type that employs compression may provide an opportunity 679 for sending a small amount of data that, when received and 680 evaluated, expands enormously to consume all of the recipient's 681 resources. All media types SHOULD state whether or not they 682 employ compression, and if they do they should discuss what steps 683 need to be taken to avoid such attacks. 685 o A media type might be targeted for applications that require some 686 sort of security assurance but not provide the necessary security 687 mechanisms themselves. For example, a media type could be defined 688 for storage of sensitive medical information that in turn requires 689 an external confidentiality and integrity protection services, or 690 which is designed for use only within a secure environment. Types 691 not requiring such services SHOULD document this in their security 692 considerations. 694 4.7. Requirements specific to XML media types 696 There are a number of additional requirements specific to the 697 registration of XML media types. These requirements are specified in 698 [RFC3023]. 700 4.8. Encoding Requirements 702 Some transports impose restrictions on the type of data they can 703 carry. For example, Internet mail traditionally was limited to 7bit 704 US-ASCII text. Encoding schemes are often used to work around such 705 transport limitations. 707 It is therefore useful to note what sort of data a media type can 708 consist of as part of its registration. An "encoding considerations" 709 field is provided for this purpose. Possible values of this field 710 are: 712 7bit: The content of the media type consists solely of CRLF- 713 delimited 7bit US-ASCII text. 715 8bit: The content of the media type consists solely of CRLF- 716 delimited 8bit text. 718 binary: The content consists of an unrestricted sequence of octets. 720 framed: The content consists of a series of frames or packets 721 without internal framing or alignment indicators. Additional out- 722 of-band information is needed to interpret the data properly, 723 including but not necessarily limited to, knowledge of the 724 boundaries between successive frames and knowledge of the 725 transport mechanism. Note that media types of this sort cannot 726 simply be stored in a file or transported as a simple stream of 727 octets; therefore, such media types are unsuitable for use in many 728 traditional protocols. A commonly used transport with framed 729 encoding is the Real-time Transport Protocol, RTP. Additional 730 rules for framed encodings defined for transport using RTP are 731 given in [RFC4855]. 733 Additional restrictions on 7bit and 8bit text are given in Section 734 4.1.1 of [RFC2046]. 736 4.9. Usage and Implementation Non-requirements 738 In the asynchronous mail environment, where information on the 739 capabilities of the remote mail agent is frequently not available to 740 the sender, maximum interoperability is attained by restricting the 741 media types used to those "common" formats expected to be widely 742 implemented. This was asserted in the past as a reason to limit the 743 number of possible media types, and resulted in a registration 744 process with a significant hurdle and delay for those registering 745 media types. 747 However, the need for "common" media types does not require limiting 748 the registration of new media types. If a limited set of media types 749 is recommended for a particular application, that should be asserted 750 by a separate applicability statement specific for the application 751 and/or environment. 753 Therefore, universal support and implementation of a media type is 754 NOT a requirement for registration. However, if a media type is 755 explicitly intended for limited use, this MUST be noted in its 756 registration. The "Restrictions on Usage" field is provided for this 757 purpose. 759 4.10. Publication Requirements 761 Media types registered in the standards tree by the IETF itself MUST 762 be published as RFCs. RFC publication of vendor and personal media 763 type registrations is allowed but not required. In all cases the 764 IANA will retain copies of all media type registrations and "publish" 765 them as part of the media types registration tree itself. 767 As stated previously, standards tree registrations for media types 768 defined in documents produced by other standards bodies MUST be 769 described by a formal standards specification produced by that body. 770 Additionally, any copyright on the registration template MUST allow 771 the IANA to copy it into the IANA registry. 773 Other than IETF registrations in the standards tree, the registration 774 of a media type does not imply endorsement, approval, or 775 recommendation by the IANA or the IETF or even certification that the 776 specification is adequate. To become Internet Standards, a protocol 777 or data object must go through the IETF standards process. While it 778 provides additional assurances when it is appropriate, this is too 779 difficult and too lengthy a process for the convenient registration 780 of media types. 782 The standards tree exists for media types that do require a 783 substantive review and approval process in a recognized standards 784 body. The vendor and personal trees exist for those media types that 785 do not require such a process. It is expected that applicability 786 statements for particular applications will be published from time to 787 time in the IETF, recommending implementation of, and support for, 788 media types that have proven particularly useful in those contexts. 790 As discussed above, registration of a top-level type requires 791 standards-track processing in the IETF and, hence, RFC publication. 793 4.11. Additional Information 795 Various sorts of optional information SHOULD be included in the 796 specification of a media type if it is available: 798 o Magic number(s) (length, octet values). Magic numbers are byte 799 sequences that are always present at a given place in the file and 800 thus can be used to identify entities as being of a given media 801 type. 803 o File name extension(s) commonly used on one or more platforms to 804 indicate that some file contains a given media type. 806 o Mac OS File Type code(s) (4 octets) used to label files containing 807 a given media type. Some discussion of Macintosh file type codes 808 and their purpose can be found in [MacOSFileTypes]. 810 o Information about how fragment/anchor identifiers [RFC3986] are 811 constructed for use in conjunction with this media type. 813 In the case of a registration in the standards tree, this additional 814 information MAY be provided in the formal specification of the media 815 type. It is suggested that this be done by incorporating the IANA 816 media type registration form into the specification itself. 818 5. Media Type Registration Procedures 820 The media type registration procedure is not a formal standards 821 process, but rather an administrative procedure intended to allow 822 community comment and sanity checking without excessive time delay. 824 The normal IETF processes should be followed for all IETF 825 registrations in the standards tree. The posting of an Internet 826 Draft is a necessary first step, followed by posting to the 827 ietf-types@iana.org list as discussed below. 829 5.1. Preliminary Community Review 831 Notice of a potential media type registration in the standards tree 832 SHOULD be sent to the ietf-types@iana.org mailing list for review. 833 This mailing list has been established for the purpose of reviewing 834 proposed media and access types. Registrations in other trees MAY be 835 sent to the list for review as well; doing so is entirely OPTIONAL, 836 but is strongly encouraged. 838 The intent of the public posting to this list is to solicit comments 839 and feedback on the choice of type/subtype name, the unambiguity of 840 the references with respect to versions and external profiling 841 information, and a review of any interoperability or security 842 considerations. The submitter may submit a revised registration 843 proposal or abandon the registration completely and at any time. 845 5.2. Submit request to IANA 847 Media types registered in the standards tree by the IETF itself MUST 848 be reviewed and approved by the IESG as part of the normal standards 849 process. Standards tree registrations by recognized standards bodies 850 as well as registrations in the vendor and personal tree should be 851 submitted directly to the IANA, unless other arrangements were made 852 as part of a liaison agreement. In either case posting the 853 registration to the ietf-types@iana.org list for review prior to 854 submission is strongly encouraged. 856 Registration requests can be sent to iana@iana.org. A web form for 857 registration requests is also available: 859 http://www.iana.org/cgi-bin/mediatypes.pl 861 5.2.1. Provisional Registrations 863 Standardization processes often take considerable time to complete. 864 In order to facilitate prototyping and testing it is often helpful to 865 assign identifiers, including but not limited to media types, early 866 in the process. This way identifiers used during standards 867 development can remain unchanged once the process is complete and 868 implementations and documentation do not have to be updated. 870 Accordingly, a provisonal registration process is provided to support 871 early assigment of media type names. A provisional registration MAY 872 be submitted to IANA for standards tree types. The only required 873 fields in such registrations are the media type name and contact 874 information (inckuding the standards body name). 876 Upon receipt of a provisionl registration, IANA will check the name 877 and contact information, then publish the registration in a separate 878 provisional registration list. 880 Provisional registrations MAY be updated or abandoned at any time. 882 5.3. Review and Approval 884 With the exception of provisional standards tree registrations, 885 registrations submitted to the IANA will be passed on to the media 886 types reviewer. The media types reviewer, who is appointed by the 887 IETF Applications Area Director(s), will review the registration to 888 make sure it meets the requirements set forth in this document. 889 Registrations that do not meet these requirements will be returned to 890 the submitter for revision. 892 Decisions made by the media types reviewer may be appealed to the 893 IESG using the procedure specified in section 6.5.4 of [RFC2026]. 895 Once a media type registration has passed review, the IANA will 896 register the media type and make the media type registration 897 available to the community. 899 In the case of standards tree registrations from other standards 900 bodies IANA will also check that the submitter is in fact a 901 recognized standards body. If the submitter is not currently 902 recognized as such the IESG will be asked to confirm their status. 903 Recognition from the IESG MUST be obtained before a standards tree 904 registration can proceed. 906 5.4. Comments on Media Type Registrations 908 Comments on registered media types may be submitted by members of the 909 community to the IANA at iana@iana.org. These comments will be 910 reviewed by the media types reviewer and then passed on to the 911 "owner" of the media type if possible. Submitters of comments may 912 request that their comment be attached to the media type registration 913 itself, and if the IANA approves of this, the comment will be made 914 accessible in conjunction with the type registration. 916 5.5. Location of Registered Media Type List 918 Media type registrations are listed by the IANA at: 920 http://www.iana.org/assignments/media-types/ 922 5.6. Change Procedures 924 Once a media type has been published by the IANA, the owner may 925 request a change to its definition. The descriptions of the 926 different registration trees above designate the "owners" of each 927 type of registration. The same procedure that would be appropriate 928 for the original registration request is used to process a change 929 request. 931 Significant changes to a media type's definition should be requested 932 only when there are serious omissions or errors in the published 933 specification. When review is required, a change request may be 934 denied if it renders entities that were valid under the previous 935 definition invalid under the new definition. 937 The owner of a media type may pass responsibility to another person 938 or agency by informing the IANA; this can be done without discussion 939 or review. 941 The IESG may reassign responsibility for a media type. The most 942 common case of this will be to enable changes to be made to types 943 where the author of the registration has died, moved out of contact 944 or is otherwise unable to make changes that are important to the 945 community. 947 Media type registrations may not be deleted; media types that are no 948 longer believed appropriate for use can be declared OBSOLETE by a 949 change to their "intended use" field; such media types will be 950 clearly marked in the lists published by the IANA. 952 5.7. Registration Template 954 Type name: 956 Subtype name: 958 Required parameters: 960 Optional parameters: 962 Encoding considerations: 964 Security considerations: 966 Interoperability considerations: 968 Published specification: 970 Applications that use this media type: 972 Additional information: 974 Deprecated alias names for this type: 975 Magic number(s): 976 File extension(s): 977 Macintosh file type code(s): 978 URI fragment/anchor identifier(s): 980 Person & email address to contact for further information: 982 Intended usage: 984 (One of COMMON, LIMITED USE or OBSOLETE.) 986 Restrictions on usage: 988 (Any restrictions on where the media type can be used go here.) 990 Author: 992 Change controller: 994 Provisional registration? (standards tree only): 996 (Any other information that the author deems interesting may be 997 added below this line.) 998 "'N/A', written exactly that way, can be used in any field if desired 999 to emphasize the fact that it does not apply or that the question was 1000 not omitted by accident. Do not use 'none' or other words that could 1001 be mistaken for a response". 1003 6. Structured Syntax Suffix Registration Procedures 1005 Someone wishing to define a "+suffix" name for a structured syntax 1006 for use with a new media type registration SHOULD: 1008 1. Check IANA's registry of media type name suffixes to see whether 1009 or not there is already an entry for that well-defined structured 1010 syntax. 1012 2. If there is no entry for their suffix scheme, fill out the 1013 template (specified in Section 6.2) and include that with the 1014 media type registration. The template may be contained in an 1015 Internet Draft, alone or as part of some other protocol 1016 specification. The template may also be submitted in some other 1017 form (as part of another document or as a stand-alone document), 1018 but the contents will be treated as an "IETF Contribution" under 1019 the guidelines of RFC 5378 [RFC5378]. 1021 3. Send a copy of the template or a pointer to the containing 1022 document (with specific reference to the section with the 1023 template) to the mailing list ietf-types@ietf.org, requesting 1024 review. This may be combined with a request to review the media 1025 type registration. Allow a reasonable time for discussion and 1026 comments. 1028 4. Respond to review comments and make revisions to the proposed 1029 registration as needed to bring it into line with the guidelines 1030 given in this document. 1032 5. Submit the (possibly updated) registration template (or pointer 1033 to the document containing it) to IANA at iana@iana.org. 1035 Upon receipt of a structured syntax suffix registration request, 1037 1. IANA checks the submission for completeness; if sections are 1038 missing or citations are not correct, IANA rejects the 1039 registration request. 1041 2. IANA checks the current registry for an entry with the same name; 1042 if such a registry exists, IANA rejects the registration request. 1044 3. IANA requests Expert Review of the registration request against 1045 the corresponding guidelines. 1047 4. The Designated Expert may request additional review or 1048 discussion, as necessary. 1050 5. If Expert Review recommends registration, IANA adds the 1051 registration to the appropriate registry. 1053 6.1. Change Procedures 1055 Registrations may be updated in each registry by the same mechanism 1056 as required for an initial registration. In cases where the original 1057 definition of the scheme is contained in an IESG-approved document, 1058 update of the specification also requires IESG approval. 1060 6.2. Structured Syntax Suffix Registration Template 1062 This template describes the fields that must be supplied in a 1063 structured syntax sufficx registration request: 1065 Name 1066 Full name of the well-defined structured syntax. 1068 +suffix 1069 Suffix used to indicate conformance to the syntax. 1071 References. 1072 Include full citations for all specifications necessary to 1073 understand the structured syntax. 1075 Encoding considerations 1076 General guidance regarding encoding considerations for any type 1077 employing this syntax should be given here. The same requirements 1078 for media type encoding considerations given in Section 4.8 apply 1079 here. 1081 Interoperability considerations 1082 Any issues regarding the interoperable use of types employing this 1083 structured syntax should be given here. Examples would include 1084 the existence of incompatible versions of the syntax, issues 1085 combining certain charsets with the syntax, or incompatibilities 1086 with other types or protocols. 1088 Security considerations 1089 Security considerations shared by media types employing this 1090 structured syntax must be specified here. The same requirements 1091 for media type security considerations given in Section 4.6 apply 1092 here, with the exception that option of not assessing the security 1093 considerations is not available for suffix registrations. 1095 Contact 1096 Person (including contact information) to contact for further 1097 information. 1099 Author/Change controller. 1100 Person (including contact information) authorized to change this 1101 suffix registration. 1103 7. Security Considerations 1105 Security requirements for media type registrations are discussed in 1106 Section 4.6. 1108 8. IANA Considerations 1110 The purpose of this document is to define IANA registries for media 1111 types and structured syntax suffixes as well as the procedures for 1112 managing these registries. Additionally, this document requires IANA 1113 to maintain a list of IESG-recognized standards bodies who are 1114 allowed to register types in the standards tree. 1116 This document also creates a new registry for structured syntax 1117 names: 1119 o The name is the "Structured Syntax Suffix" registry. 1121 o The registration process is specified in Section 6. 1123 o The information required for a registry entry as well as the entry 1124 format are specified in Section 6.2. 1126 o The initial content of the registry shall be constructed at the 1127 time of the registry's creation by the designated media types 1128 reviewer(s) by examining the current media types registry and 1129 extracting all conforming uses of "+suffix" names. 1131 9. Acknowledgements 1133 The current authors would like to acknowledge their debt to the late 1134 Dr. Jon Postel, whose general model of IANA registration procedures 1135 and specific contributions shaped the predecessors of this document 1136 [RFC2048]. We hope that the current version is one with which he 1137 would have agreed but, as it is impossible to verify that agreement, 1138 we have regretfully removed his name as a co-author. 1140 Barry Leiba and Alexey Melnikov provided many helpful review comments 1141 and suggestions. 1143 10. References 1145 10.1. Normative References 1147 [I-D.ietf-appsawg-mime-default-charset] 1148 Melnikov, A. and J. Reschke, "Update to MIME regarding 1149 Charset Parameter Handling in Textual Media Types", 1150 draft-ietf-appsawg-mime-default-charset-00 (work in 1151 progress), February 2012. 1153 [RFC2045] Freed, N. and N. Borenstein, "Multipurpose Internet Mail 1154 Extensions (MIME) Part One: Format of Internet Message 1155 Bodies", RFC 2045, November 1996. 1157 [RFC2046] Freed, N. and N. Borenstein, "Multipurpose Internet Mail 1158 Extensions (MIME) Part Two: Media Types", RFC 2046, 1159 November 1996. 1161 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 1162 Requirement Levels", BCP 14, RFC 2119, March 1997. 1164 [RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., 1165 Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext 1166 Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999. 1168 [RFC2978] Freed, N. and J. Postel, "IANA Charset Registration 1169 Procedures", BCP 19, RFC 2978, October 2000. 1171 [RFC3023] Murata, M., St. Laurent, S., and D. Kohn, "XML Media 1172 Types", RFC 3023, January 2001. 1174 [RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO 1175 10646", STD 63, RFC 3629, November 2003. 1177 [RFC3979] Bradner, S., "Intellectual Property Rights in IETF 1178 Technology", BCP 79, RFC 3979, March 2005. 1180 [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform 1181 Resource Identifier (URI): Generic Syntax", STD 66, 1182 RFC 3986, January 2005. 1184 [RFC4855] Casner, S., "Media Type Registration of RTP Payload 1185 Formats", RFC 4855, February 2007. 1187 [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an 1188 IANA Considerations Section in RFCs", BCP 26, RFC 5226, 1189 May 2008. 1191 [RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax 1192 Specifications: ABNF", STD 68, RFC 5234, January 2008. 1194 [RFC5378] Bradner, S. and J. Contreras, "Rights Contributors Provide 1195 to the IETF Trust", BCP 78, RFC 5378, November 2008. 1197 [RFC6532] Yang, A., Steel, S., and N. Freed, "Internationalized 1198 Email Headers", RFC 6532, January 2012. 1200 10.2. Informative References 1202 [MacOSFileTypes] 1203 Apple Computer, Inc., "Mac OS: File Type and Creator 1204 Codes, and File Formats", Apple Knowledge Base Article 1205 55381, June 1993, 1206 . 1208 [RFC2026] Bradner, S., "The Internet Standards Process -- Revision 1209 3", BCP 9, RFC 2026, October 1996. 1211 [RFC2048] Freed, N., Klensin, J., and J. Postel, "Multipurpose 1212 Internet Mail Extensions (MIME) Part Four: Registration 1213 Procedures", BCP 13, RFC 2048, November 1996. 1215 [RFC2231] Freed, N. and K. Moore, "MIME Parameter Value and Encoded 1216 Word Extensions: 1217 Character Sets, Languages, and Continuations", RFC 2231, 1218 November 1997. 1220 Appendix A. Grandfathered Media Types 1222 A number of media types with unfaceted names, registered prior to 1223 1996, would, if registered under the guidelines in this document, be 1224 given a faceted name and placed into either the vendor or personal 1225 trees. Reregistration of those types to reflect the appropriate 1226 trees is encouraged but not required. Ownership and change control 1227 principles outlined in this document apply to those types as if they 1228 had been registered in the trees described above. 1230 From time to time there may also be cases where a media type with an 1231 unfaceted name has been widely deployed without being registered. If 1232 possible such types SHOULD be reregistered with a proper faceted 1233 name. However, if this is not possible the type can, subject to 1234 approval by both the media types reviewer and the IESG, be registered 1235 in the proper tree with its unfaceted name. 1237 Appendix B. Open Issues 1239 o The list of fields in the registration is getting long. Should 1240 the fields be numbered and referred to by number in order to 1241 facilitate translation into other languages and similar 1242 activities? 1244 o Currently anyone can register a vendor media type on behalf of a 1245 vendor but subsequent to that only the vendor can make changes. 1246 Do we want to retain this restriction? 1248 o Should we add a field to the registration template where limited- 1249 use media types can provide an explicit list of the applications 1250 that employ that type? 1252 Appendix C. Changes Since RFC 4288 1254 o Suffixes to indicate the use of a particular structured syntax are 1255 now fully specified and a suffix registration process has been 1256 defined. 1258 o Registration of widely deployed unregistered unfaceted type names 1259 in the vendor or personal trees is now allowed, subject to 1260 approval by the media types reviewer and the IESG. 1262 o The standards tree registration process has been revised to 1263 include Expert Review and generalized to address cases like media 1264 types in non-IETF stream documents. 1266 o A field for fragment/anchor identifiers has been added to the 1267 registration template. 1269 o The specification requirements for personal tree registrations 1270 have been changed to be the same as those for the vendor tree. 1271 The text has been changed to encourage (but not require) 1272 specification availability. 1274 o The definition of additional trees has been clarified to state 1275 that an IETF Standards Action is required. 1277 o Widely deployed types with "X-" names can now be registered as an 1278 exception in the vendor tree. 1280 o The reqiremeents on changes to registrations have been loosened so 1281 minor changes are easier to make. 1283 o The registration process has been completely restructured so that 1284 with the exception of IETF-generated types in the standards tree, 1285 all requests are procesed by IANA and not the IESG. 1287 o A provisional registration process has been added for early 1288 assignment of types in the standards tree. 1290 o Many editorial changes have been made throughout the document to 1291 make the requirements and processes it describes clearer and 1292 easier to follow. 1294 o Added the ability to specify a list of deprecated aliases. 1296 Authors' Addresses 1298 Ned Freed 1299 Oracle 1300 800 Royal Oaks 1301 Monrovia, CA 91016-6347 1302 USA 1304 Email: ned+ietf@mrochek.com 1306 John C. Klensin 1307 1770 Massachusetts Ave, #322 1308 Cambridge, MA 02140 1309 USA 1311 Email: john+ietf@jck.com 1313 Tony Hansen 1314 AT&T Laboratories 1315 200 Laurel Ave. 1316 Middletown, NJ 07748 1317 USA 1319 Email: tony+mtsuffix@maillennium.att.com