Internet Engineering Task Force (IETF) N. Freed
Request for Comments: 6838 Oracle
BCP: 13 J. Klensin
Obsoletes: 4288
Category: Best Current Practice T. Hansen
ISSN: 2070-1721 AT&T Laboratories
January 2013
Internet Engineering Task Force (IETF) N. Freed
Request for Comments: 6838 Oracle
BCP: 13 J. Klensin
Obsoletes: 4288
Category: Best Current Practice T. Hansen
ISSN: 2070-1721 AT&T Laboratories
January 2013
Media Type Specifications and Registration Procedures
媒体类型规格和注册程序
Abstract
摘要
This document defines procedures for the specification and registration of media types for use in HTTP, MIME, and other Internet protocols.
本文档定义了HTTP、MIME和其他Internet协议中使用的媒体类型的规范和注册过程。
Status of This Memo
关于下段备忘
This memo documents an Internet Best Current Practice.
本备忘录记录了互联网最佳实践。
This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on BCPs is available in Section 2 of RFC 5741.
本文件是互联网工程任务组（IETF）的产品。它代表了IETF社区的共识。它已经接受了公众审查，并已被互联网工程指导小组（IESG）批准出版。有关BCP的更多信息，请参见RFC 5741第2节。
Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc6838.
有关本文件当前状态、任何勘误表以及如何提供反馈的信息，请访问http://www.rfc-editor.org/info/rfc6838.
Copyright Notice
版权公告
Copyright (c) 2013 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2013 IETF信托基金和确定为文件作者的人员。版权所有。
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.
本文件受BCP 78和IETF信托有关IETF文件的法律规定的约束(http://trustee.ietf.org/license-info)自本文件出版之日起生效。请仔细阅读这些文件，因为它们描述了您对本文件的权利和限制。从本文件中提取的代码组件必须包括信托法律条款第4.e节中所述的简化BSD许可证文本，并提供简化BSD许可证中所述的无担保。
Table of Contents
目录
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Historical Note . . . . . . . . . . . . . . . . . . . . . 3
1.2. Conventions Used in This Document . . . . . . . . . . . . 4
2. Media Type Registration Preliminaries . . . . . . . . . . . . 4
3. Registration Trees and Subtype Names . . . . . . . . . . . . . 4
3.1. Standards Tree . . . . . . . . . . . . . . . . . . . . . . 4
3.2. Vendor Tree . . . . . . . . . . . . . . . . . . . . . . . 6
3.3. Personal or Vanity Tree . . . . . . . . . . . . . . . . . 6
3.4. Unregistered x. Tree . . . . . . . . . . . . . . . . . . . 7
3.5. Additional Registration Trees . . . . . . . . . . . . . . 7
4. Registration Requirements . . . . . . . . . . . . . . . . . . 7
4.1. Functionality Requirement . . . . . . . . . . . . . . . . 8
4.2. Naming Requirements . . . . . . . . . . . . . . . . . . . 8
4.2.1. Text Media Types . . . . . . . . . . . . . . . . . . . 9
4.2.2. Image Media Types . . . . . . . . . . . . . . . . . . 10
4.2.3. Audio Media Types . . . . . . . . . . . . . . . . . . 10
4.2.4. Video Media Types . . . . . . . . . . . . . . . . . . 10
4.2.5. Application Media Types . . . . . . . . . . . . . . . 11
4.2.6. Multipart and Message Media Types . . . . . . . . . . 11
4.2.7. Additional Top-Level Types . . . . . . . . . . . . . . 12
4.2.8. Structured Syntax Name Suffixes . . . . . . . . . . . 12
4.2.9. Deprecated Aliases . . . . . . . . . . . . . . . . . . 13
4.3. Parameter Requirements . . . . . . . . . . . . . . . . . . 13
4.4. Canonicalization and Format Requirements . . . . . . . . . 14
4.5. Interchange Recommendations . . . . . . . . . . . . . . . 15
4.6. Security Requirements . . . . . . . . . . . . . . . . . . 15
4.7. Requirements Specific to XML Media Types . . . . . . . . . 16
4.8. Encoding Requirements . . . . . . . . . . . . . . . . . . 16
4.9. Usage and Implementation Non-Requirements . . . . . . . . 17
4.10. Publication Requirements . . . . . . . . . . . . . . . . . 18
4.11. Fragment Identifier Requirements . . . . . . . . . . . . . 18
4.12. Additional Information . . . . . . . . . . . . . . . . . . 19
5. Media Type Registration Procedures . . . . . . . . . . . . . . 19
5.1. Preliminary Community Review . . . . . . . . . . . . . . . 19
5.2. Submit Request to IANA . . . . . . . . . . . . . . . . . . 20
5.2.1. Provisional Registrations . . . . . . . . . . . . . . 20
5.3. Review and Approval . . . . . . . . . . . . . . . . . . . 21
5.4. Comments on Media Type Registrations . . . . . . . . . . . 21
5.5. Change Procedures . . . . . . . . . . . . . . . . . . . . 21
5.6. Registration Template . . . . . . . . . . . . . . . . . . 22
6. Structured Syntax Suffix Registration Procedures . . . . . . . 23
6.1. Change Procedures . . . . . . . . . . . . . . . . . . . . 24
6.2. Structured Syntax Suffix Registration Template . . . . . . 24
7. Security Considerations . . . . . . . . . . . . . . . . . . . 25
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 26
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 27
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Historical Note . . . . . . . . . . . . . . . . . . . . . 3
1.2. Conventions Used in This Document . . . . . . . . . . . . 4
2. Media Type Registration Preliminaries . . . . . . . . . . . . 4
3. Registration Trees and Subtype Names . . . . . . . . . . . . . 4
3.1. Standards Tree . . . . . . . . . . . . . . . . . . . . . . 4
3.2. Vendor Tree . . . . . . . . . . . . . . . . . . . . . . . 6
3.3. Personal or Vanity Tree . . . . . . . . . . . . . . . . . 6
3.4. Unregistered x. Tree . . . . . . . . . . . . . . . . . . . 7
3.5. Additional Registration Trees . . . . . . . . . . . . . . 7
4. Registration Requirements . . . . . . . . . . . . . . . . . . 7
4.1. Functionality Requirement . . . . . . . . . . . . . . . . 8
4.2. Naming Requirements . . . . . . . . . . . . . . . . . . . 8
4.2.1. Text Media Types . . . . . . . . . . . . . . . . . . . 9
4.2.2. Image Media Types . . . . . . . . . . . . . . . . . . 10
4.2.3. Audio Media Types . . . . . . . . . . . . . . . . . . 10
4.2.4. Video Media Types . . . . . . . . . . . . . . . . . . 10
4.2.5. Application Media Types . . . . . . . . . . . . . . . 11
4.2.6. Multipart and Message Media Types . . . . . . . . . . 11
4.2.7. Additional Top-Level Types . . . . . . . . . . . . . . 12
4.2.8. Structured Syntax Name Suffixes . . . . . . . . . . . 12
4.2.9. Deprecated Aliases . . . . . . . . . . . . . . . . . . 13
4.3. Parameter Requirements . . . . . . . . . . . . . . . . . . 13
4.4. Canonicalization and Format Requirements . . . . . . . . . 14
4.5. Interchange Recommendations . . . . . . . . . . . . . . . 15
4.6. Security Requirements . . . . . . . . . . . . . . . . . . 15
4.7. Requirements Specific to XML Media Types . . . . . . . . . 16
4.8. Encoding Requirements . . . . . . . . . . . . . . . . . . 16
4.9. Usage and Implementation Non-Requirements . . . . . . . . 17
4.10. Publication Requirements . . . . . . . . . . . . . . . . . 18
4.11. Fragment Identifier Requirements . . . . . . . . . . . . . 18
4.12. Additional Information . . . . . . . . . . . . . . . . . . 19
5. Media Type Registration Procedures . . . . . . . . . . . . . . 19
5.1. Preliminary Community Review . . . . . . . . . . . . . . . 19
5.2. Submit Request to IANA . . . . . . . . . . . . . . . . . . 20
5.2.1. Provisional Registrations . . . . . . . . . . . . . . 20
5.3. Review and Approval . . . . . . . . . . . . . . . . . . . 21
5.4. Comments on Media Type Registrations . . . . . . . . . . . 21
5.5. Change Procedures . . . . . . . . . . . . . . . . . . . . 21
5.6. Registration Template . . . . . . . . . . . . . . . . . . 22
6. Structured Syntax Suffix Registration Procedures . . . . . . . 23
6.1. Change Procedures . . . . . . . . . . . . . . . . . . . . 24
6.2. Structured Syntax Suffix Registration Template . . . . . . 24
7. Security Considerations . . . . . . . . . . . . . . . . . . . 25
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 26
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 27
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 27
10.1. Normative References . . . . . . . . . . . . . . . . . . . 27
10.2. Informative References . . . . . . . . . . . . . . . . . . 28
Appendix A. Grandfathered Media Types . . . . . . . . . . . . . . 30
Appendix B. Changes since RFC 4288 . . . . . . . . . . . . . . . 30
10. References . . . . . . . . . . . . . . . . . . . . . . . . . . 27
10.1. Normative References . . . . . . . . . . . . . . . . . . . 27
10.2. Informative References . . . . . . . . . . . . . . . . . . 28
Appendix A. Grandfathered Media Types . . . . . . . . . . . . . . 30
Appendix B. Changes since RFC 4288 . . . . . . . . . . . . . . . 30
Recent Internet protocols have been carefully designed to be easily extensible in certain areas. In particular, many protocols, including but not limited to HTTP [RFC2616] and MIME [RFC2045], are capable of carrying arbitrary labeled content.
最近的互联网协议经过精心设计，在某些领域易于扩展。特别是，许多协议，包括但不限于HTTP[RFC2616]和MIME[RFC2045]，能够承载任意标记的内容。
The mechanism used to label such content is a media type, consisting of a top-level type and a subtype, which is further structured into trees. Optionally, media types can define companion data, known as parameters.
用于标记此类内容的机制是媒体类型，由顶级类型和子类型组成，该类型进一步结构化为树。或者，介质类型可以定义伴随数据，称为参数。
A registration process is needed for these labels, so that the set of such values are defined in a reasonably orderly, well-specified, and public manner.
这些标签需要注册过程，以便以合理有序、明确规定和公开的方式定义这组值。
This document specifies the criteria for media type registrations and defines the procedures to be used to register media types (Section 5) as well as media type structured suffixes (Section 6) in the Internet Assigned Numbers Authority (IANA) central registry.
本文件规定了媒体类型注册的标准，并定义了在互联网分配号码管理局（IANA）中央注册中心注册媒体类型（第5节）以及媒体类型结构化后缀（第6节）的程序。
The location of the media type registry managed by these procedures is:
由这些过程管理的媒体类型注册表的位置为：
http://www.iana.org/assignments/media-types/
http://www.iana.org/assignments/media-types/
The media type registration process was initially defined for registering media types for use in the context of the asynchronous Internet mail environment. In this mail environment, there is a need to limit the number of possible media types, to increase the likelihood of interoperability when the capabilities of the remote mail system are not known. As media types are used in new environments in which the proliferation of media types is not a hindrance to interoperability, the original procedure proved excessively restrictive and had to be generalized. This was initially done in [RFC2048], but the procedure defined there was still part of the MIME document set. The media type specification and registration procedure is now a separate document, to make it clear that it is independent of MIME.
媒体类型注册过程最初定义为注册在异步Internet邮件环境中使用的媒体类型。在这种邮件环境中，需要限制可能的媒体类型的数量，以便在远程邮件系统的功能未知时增加互操作性的可能性。由于媒体类型在新环境中使用，在新环境中，媒体类型的扩散不会妨碍互操作性，因此，原来的过程被证明限制过多，必须加以推广。这最初是在[RFC2048]中完成的，但是在那里定义的过程仍然是MIME文档集的一部分。媒体类型规范和注册过程现在是一个单独的文档，以明确它独立于MIME。
It may be desirable to restrict the use of media types to specific environments or to prohibit their use in other environments. This specification incorporates such restrictions into media type registrations in a systematic way. See Section 4.9 for additional discussion.
可能需要将媒体类型的使用限制在特定环境中，或禁止在其他环境中使用。本规范系统地将此类限制纳入媒体类型注册中。更多讨论见第4.9节。
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119] when they appear in ALL CAPS. They may also appear in lower or mixed case as plain English words, without any normative meaning.
本文件中的关键词“必须”、“不得”、“要求”、“应”、“不得”、“应”、“不应”、“建议”、“可”和“可选”在所有大写字母中出现时，应按照[RFC2119]中的说明进行解释。它们也可能出现在小写或混合大写的普通英语单词中，没有任何规范意义。
This specification makes use of the Augmented Backus-Naur Form (ABNF) [RFC5234] notation, including the core rules defined in Appendix B of that document.
本规范使用了扩展的巴科斯诺尔表（ABNF）[RFC5234]符号，包括该文件附录B中定义的核心规则。
Registration of a new media type or types starts with the construction of a registration proposal. Registration may occur within several different registration trees that have different requirements, as discussed below. In general, a new registration proposal is circulated and reviewed in a fashion appropriate to the tree involved. The media type is then registered if the proposal is acceptable. The following sections describe the requirements and procedures used for each of the different registration trees.
一种或多种新媒体类型的注册从构建注册提案开始。注册可能发生在具有不同要求的几个不同的注册树中，如下所述。一般来说，新的登记提案以适合所涉树木的方式分发和审查。如果建议可接受，则注册媒体类型。以下各节描述了用于每个不同注册树的要求和程序。
In order to increase the efficiency and flexibility of the registration process, different structures of subtype names can be registered to accommodate the different natural requirements for, e.g., a subtype that will be recommended for wide support and implementation by the Internet community, or a subtype that is used to move files associated with proprietary software. The following subsections define registration "trees" that are distinguished by the use of faceted names, e.g., subtype names that begin with a "tree." prefix. Note that some media types defined prior to this document do not conform to the naming conventions described below. See Appendix A for a discussion of them.
为了提高注册过程的效率和灵活性，可以注册不同结构的子类型名称，以适应不同的自然要求，例如，互联网社区将推荐广泛支持和实施的子类型，或用于移动与专有软件关联的文件的子类型。以下小节定义了通过使用刻面名称来区分的注册“树”，例如，以“tree.”前缀开头的子类型名称。请注意，本文档之前定义的某些媒体类型不符合下面描述的命名约定。关于它们的讨论，见附录A。
The standards tree is intended for types of general interest to the Internet community. Registrations in the standards tree MUST be either:
标准树用于互联网社区普遍感兴趣的类型。标准树中的注册必须是：
1. in the case of registrations associated with IETF specifications, approved directly by the IESG, or
1. 对于与IETF规范相关的注册，由IESG直接批准，或
2. registered by a recognized standards-related organization using the "Specification Required" IANA registration policy [RFC5226] (which implies Expert Review).
2. 由公认的标准相关组织使用“所需规范”IANA注册政策[RFC5226]注册（这意味着专家审查）。
The first procedure is used for registrations from IETF Consensus documents, or in rare cases when registering a grandfathered (see Appendix A) and/or otherwise incomplete registration is in the interest of the Internet community. The registration proposal MUST be published as an RFC. When the registration RFC is in the IETF stream, it must have IETF Consensus, which can be attained with a status of Standards Track, BCP, Informational, or Experimental. Registrations published in non-IETF RFC streams are also allowed and require IESG approval. A registration can be either in a stand-alone "registration only" RFC or incorporated into a more general specification of some sort.
第一个程序用于IETF共识文件中的注册，或在少数情况下，当注册一个祖父（见附录a）和/或其他不完整的注册符合互联网社区的利益时。注册提案必须以RFC的形式发布。当注册RFC在IETF流中时，它必须具有IETF共识，这可以通过标准跟踪、BCP、信息或实验状态来实现。也允许在非IETF RFC流中发布注册，并需要IESG批准。注册可以在独立的“仅注册”RFC中进行，也可以合并到某种更通用的规范中。
In the second case, the IESG makes a one-time decision on whether the registration submitter represents a recognized standards-related organization; after that, a Media Types Reviewer (Designated Expert or a group of Designated Experts) performs the Expert Review as specified in this document. Subsequent submissions from the same source do not involve the IESG. The format MUST be described by a formal standards specification produced by the submitting standards-related organization.
在第二种情况下，IESG一次性决定注册提交人是否代表公认的标准相关组织；之后，媒体类型审查员（指定专家或指定专家组）按照本文件的规定进行专家审查。同一来源的后续提交不涉及IESG。格式必须由提交标准的相关组织制定的正式标准规范描述。
Media types in the standards tree MUST NOT have faceted names, unless they are grandfathered in using the process described in Appendix A.
标准树中的媒体类型不得具有刻面名称，除非在使用附录A中描述的过程中对其进行了加粗。
The "owner" of a media type registered in the standards tree is assumed to be the standards-related organization itself. Modification or alteration of the specification uses the same level of processing (e.g., a registration submitted on Standards Track can be revised in another Standards Track RFC, but cannot be revised in an Informational RFC) required for the initial registration.
在标准树中注册的媒体类型的“所有者”被假定为与标准相关的组织本身。规范的修改或变更使用初始注册所需的相同处理级别（例如，在标准轨道上提交的注册可以在另一标准轨道RFC中修改，但不能在信息RFC中修改）。
Standards-tree registrations from recognized standards-related organizations are submitted directly to the IANA, where they will undergo Expert Review [RFC5226] prior to approval. In this case, the Expert Reviewer(s) will, among other things, ensure that the required specification provides adequate documentation.
来自公认标准相关组织的标准树注册直接提交给IANA，在批准之前，将在IANA进行专家评审[RFC5226]。在这种情况下，除其他事项外，专家评审员将确保所需规范提供足够的文件。
The vendor tree is used for media types associated with publicly available products. "Vendor" and "producer" are construed very broadly in this context and are considered equivalent. Note that industry consortia as well as non-commercial entities that do not qualify as recognized standards-related organizations can quite appropriately register media types in the vendor tree.
供应商树用于与公共可用产品关联的媒体类型。“供应商”和“生产商”在此上下文中的解释非常宽泛，并被视为等效。请注意，行业联盟以及不符合公认标准相关组织资格的非商业实体可以非常适当地在供应商树中注册媒体类型。
A registration may be placed in the vendor tree by anyone who needs to interchange files associated with some product or set of products. However, the registration properly belongs to the vendor or organization producing the software that employs the type being registered, and that vendor or organization can at any time elect to assert ownership of a registration done by a third party in order to correct or update it. See Section 5.5 for additional information.
需要交换与某些产品或产品集相关的文件的任何人都可以将注册放在供应商树中。但是，注册应属于生产使用被注册类型的软件的供应商或组织，该供应商或组织可在任何时候选择主张对第三方完成的注册的所有权，以便对其进行更正或更新。更多信息见第5.5节。
When a third party registers a type on behalf of someone else, both entities SHOULD be noted in the Change Controller field in the registration. One possible format for this would be "Foo, on behalf of Bar".
当第三方代表其他人注册类型时，应在注册中的更改控制器字段中注明这两个实体。一种可能的格式是“Foo，代表酒吧”。
Vendor-tree registrations will be distinguished by the leading facet "vnd.". That may be followed, at the discretion of the registrant, by either a media subtype name from a well-known producer (e.g., "vnd.mudpie") or by an IANA-approved designation of the producer's name that is followed by a media type or product designation (e.g., vnd.bigcompany.funnypictures).
供应商树注册将通过前面的方面“vnd”来区分。由注册人自行决定，可由知名制作人提供媒体子类型名称（如“vnd.mudpie”），或由IANA批准的制作人名称命名，后跟媒体类型或产品名称（如vnd.bigcompany.funnypictures）。
While public exposure and review of media types to be registered in the vendor tree are not required, using the media-types@iana.org mailing list for review is encouraged, to improve the quality of those specifications. Registrations in the vendor tree may be submitted directly to the IANA, where they will undergo Expert Review [RFC5226] prior to approval.
虽然不需要公开披露和审查要在供应商树中注册的媒体类型，但使用-types@iana.org鼓励使用邮件列表进行审查，以提高这些规范的质量。供应商目录树中的注册可直接提交给IANA，在批准之前，将在IANA进行专家审查[RFC5226]。
Registrations for media types created experimentally or as part of products that are not distributed commercially may be registered in the personal or vanity tree. The registrations are distinguished by the leading facet "prs.".
对于实验性创建的媒体类型或作为非商业发行产品的一部分创建的媒体类型的注册可以在个人或虚荣树中注册。注册以“prs”为主要方面进行区分。
The owner of "personal" registrations and associated specifications is the person or entity making the registration, or one to whom responsibility has been transferred as described below.
“个人”注册和相关规范的所有人是进行注册的个人或实体，或已按照下文所述将责任转移给的个人或实体。
While public exposure and review of media types to be registered in the personal tree are not required, using the media-types@iana.org mailing list (see Section 5.1) for review is encouraged, to improve the quality of those specifications. Registrations in the personal tree may be submitted directly to the IANA, where they will undergo Expert Review [RFC5226] prior to approval.
虽然不需要公开曝光和审查要在个人目录树中注册的媒体类型，但使用媒体-types@iana.org鼓励使用邮件列表（见第5.1节）进行审查，以提高这些规范的质量。个人目录树中的注册可直接提交给IANA，在批准之前，将在IANA进行专家审查[RFC5226]。
Subtype names with "x." as the first facet may be used for types intended exclusively for use in private, local environments. Types in this tree cannot be registered and are intended for use only with the active agreement of the parties exchanging them.
第一个方面为“x”的子类型名称可用于专用于私有本地环境的类型。无法注册此树中的类型，只能在交换这些类型的各方达成有效协议的情况下使用。
However, with the simplified registration procedures described above for vendor and personal trees, it should rarely, if ever, be necessary to use unregistered types. Therefore, use of types in the "x." tree is strongly discouraged.
然而，由于上述针对供应商和个人树的简化注册程序，应该很少（如果有的话）需要使用未注册的类型。因此，强烈反对在“x”树中使用类型。
Note that types with names beginning with "x-" are no longer considered to be members of this tree (see [RFC6648]). Also note that if a generally useful and widely deployed type incorrectly ends up with an "x-" name prefix, it MAY be registered using its current name in an alternative tree by following the procedure defined in Appendix A.
请注意，名称以“x-”开头的类型不再被视为此树的成员（请参见[RFC6648]）。还请注意，如果一个普遍有用且广泛部署的类型错误地以“x-”名称前缀结束，则可以按照附录a中定义的过程，在替代树中使用其当前名称进行注册。
From time to time and as required by the community, new top-level registration trees may be created by IETF Standards Action. It is explicitly assumed that these trees may be created for external registration and management by well-known permanent organizations; for example, scientific societies may register media types specific to the sciences they cover. In general, the quality of review of specifications for one of these additional registration trees is expected to be equivalent to registrations in the standards tree by a recognized standards-related organization. When the IETF performs such review, it needs to consider the greater expertise of the requesting organization with respect to the subject media type.
根据社区的要求，IETF标准行动可不时创建新的顶级注册树。明确假设这些树可由知名的常设组织创建用于外部注册和管理；例如，科学协会可能会登记他们所涵盖的科学的特定媒体类型。一般来说，这些附加注册树之一的规范审查质量应等同于公认的标准相关组织在标准树中的注册。当IETF执行这样的审查时，它需要考虑请求组织相对于主题媒体类型的更高的专门知识。
Media type registrations are all expected to conform to various requirements laid out in the following sections. Note that requirement specifics sometimes vary depending on the registration tree, again as detailed in the following sections.
媒体类型注册均应符合以下各节规定的各种要求。请注意，需求细节有时会因注册树的不同而有所不同，这一点在以下章节中也有详细说明。
Media types MUST function as actual media formats. Registration of things that are better thought of as a transfer encoding, as a charset, or as a collection of separate entities of another type, is not allowed. For example, although applications exist to decode the base64 transfer encoding [RFC2045], base64 cannot be registered as a media type.
介质类型必须与实际介质格式相同。不允许注册更好地被认为是传输编码、字符集或其他类型的独立实体集合的内容。例如，尽管存在用于解码base64传输编码[RFC2045]的应用程序，但base64不能注册为媒体类型。
This requirement applies regardless of the registration tree involved.
这一要求适用于任何涉及的注册树。
All registered media types MUST be assigned top-level type and subtype names. The combination of these names serves to uniquely identify the media type, and the subtype name facet (or the absence of one) identifies the registration tree. Both top-level type and subtype names are case-insensitive.
必须为所有注册的媒体类型分配顶级类型和子类型名称。这些名称的组合用于唯一标识媒体类型，而子类型名称facet（或没有）标识注册树。顶级类型名和子类型名都不区分大小写。
Type and subtype names MUST conform to the following ABNF:
类型和子类型名称必须符合以下ABNF：
type-name = restricted-name subtype-name = restricted-name
类型名称=受限名称子类型名称=受限名称
restricted-name = restricted-name-first *126restricted-name-chars
restricted-name-first = ALPHA / DIGIT
restricted-name-chars = ALPHA / DIGIT / "!" / "#" /
"$" / "&" / "-" / "^" / "_"
restricted-name-chars =/ "." ; Characters before first dot always
; specify a facet name
restricted-name-chars =/ "+" ; Characters after last plus always
; specify a structured syntax suffix
restricted-name = restricted-name-first *126restricted-name-chars
restricted-name-first = ALPHA / DIGIT
restricted-name-chars = ALPHA / DIGIT / "!" / "#" /
"$" / "&" / "-" / "^" / "_"
restricted-name-chars =/ "." ; Characters before first dot always
; specify a facet name
restricted-name-chars =/ "+" ; Characters after last plus always
; specify a structured syntax suffix
Note that this syntax is somewhat more restrictive than what is allowed by the ABNF in Section 5.1 of [RFC2045] or Section 4.2 of [RFC4288]. Also note that while this syntax allows names of up to 127 characters, implementation limits may make such long names problematic. For this reason, <type-name> and <subtype-name> SHOULD be limited to 64 characters.
注意，这种语法比[RFC2045]第5.1节或[RFC4288]第4.2节中ABNF所允许的限制性更强。还请注意，虽然此语法允许最多127个字符的名称，但实现限制可能会使这样长的名称出现问题。因此，<type name>和<subtype name>应限制为64个字符。
Although the name syntax treats "." as equivalent to any other character, characters before any initial "." always specify the registration facet. Note that this means that facet-less standards-tree registrations cannot use periods in the subtype name.
尽管名称语法将“.”视为等同于任何其他字符，但任何首字母“.”之前的字符始终指定注册方面。请注意，这意味着无刻面标准树注册不能在子类型名称中使用句点。
Similarly, the final "+" in a subtype name introduces a structured syntax specifier suffix. Structured syntax suffix requirements are specified in Section 4.2.8.
类似地，子类型名称中的最后一个“+”引入了结构化语法说明符后缀。第4.2.8节规定了结构化语法后缀要求。
While it is possible for a given media type to be assigned additional names, the use of different names to identify the same media type is discouraged.
虽然可以为给定的媒体类型分配额外的名称，但不鼓励使用不同的名称来标识相同的媒体类型。
These requirements apply regardless of the registration tree involved.
这些要求适用于任何涉及的注册树。
The choice of top-level type MUST take into account the nature of media type involved. New subtypes of top-level types MUST conform to the restrictions of the top-level type, if any. The following sections describe each of the initial set of top-level types and their associated restrictions. Additionally, various protocols, including but not limited to HTTP and MIME, MAY impose additional restrictions on the media types they can transport. (See [RFC2046] for additional information on the restrictions MIME imposes.)
顶级类型的选择必须考虑所涉及媒体类型的性质。顶级类型的新子类型必须符合顶级类型（如果有）的限制。以下各节描述了每个顶级类型的初始集合及其相关限制。此外，各种协议（包括但不限于HTTP和MIME）可能会对它们可以传输的媒体类型施加额外的限制。（有关MIME施加的限制的更多信息，请参见[RFC2046]）
The "text" top-level type is intended for sending material that is principally textual in form.
“文本”顶级类型用于发送主要是文本形式的材料。
Many subtypes of text, notably including the subtype "text/plain", which is a generic subtype for plain text defined in [RFC2046], define a "charset" parameter. If a "charset" parameter is defined for a particular subtype of text, it MUST be used to specify a charset name defined in accordance to the procedures laid out in [RFC2978].
文本的许多子类型，尤其包括子类型“text/plain”，它是[RFC2046]中定义的纯文本的通用子类型，定义了“charset”参数。如果为特定文本子类型定义了“字符集”参数，则必须使用该参数指定根据[RFC2978]中规定的程序定义的字符集名称。
As specified in [RFC6657], a "charset" parameter SHOULD NOT be specified when charset information is transported inside the payload (e.g., as in "text/xml").
如[RFC6657]中所述，当在有效负载内传输字符集信息时，不应指定“字符集”参数（如“text/xml”）。
If a "charset" parameter is specified, it SHOULD be a required parameter, eliminating the options of specifying a default value. If there is a strong reason for the parameter to be optional despite this advice, each subtype MAY specify its own default value, or alternatively, it MAY specify that there is no default value. Finally, the "UTF-8" charset [RFC3629] SHOULD be selected as the default. See [RFC6657] for additional information on the use of "charset" parameters in conjunction with subtypes of text.
如果指定了“charset”参数，则该参数应为必需参数，从而消除了指定默认值的选项。如果尽管有此建议，参数仍然是可选的，那么每个子类型都可以指定自己的默认值，或者，也可以指定没有默认值。最后，应选择“UTF-8”字符集[RFC3629]作为默认值。有关将“字符集”参数与文本子类型结合使用的更多信息，请参见[RFC6657]。
Regardless of what approach is chosen, all new text/* registrations
MUST clearly specify how the charset is determined; relying on the
US-ASCII default defined in Section 4.1.2 of [RFC2046] is no longer
Regardless of what approach is chosen, all new text/* registrations
MUST clearly specify how the charset is determined; relying on the
US-ASCII default defined in Section 4.1.2 of [RFC2046] is no longer
permitted. If explanatory text is needed, this SHOULD be placed in the additional information section of the registration.
被允许如果需要解释性文本，应将其放在注册的附加信息部分。
Plain text does not provide for or allow formatting commands, font attribute specifications, processing instructions, interpretation directives, or content markup. Plain text is seen simply as a linear sequence of characters, possibly interrupted by line breaks or page breaks. Plain text MAY allow the stacking of several characters in the same position in the text. Plain text in scripts like Arabic and Hebrew may also include facilities that allow the arbitrary mixing of text segments with different writing directions.
纯文本不提供或允许格式化命令、字体属性规范、处理指令、解释指令或内容标记。纯文本被简单地看作是一个线性字符序列，可能被换行符或分页符打断。纯文本可以允许在文本中的同一位置堆叠多个字符。阿拉伯文和希伯来文等脚本中的纯文本也可能包含允许任意混合具有不同书写方向的文本段的功能。
Beyond plain text, there are many formats for representing what might be known as "rich text". An interesting characteristic of many such representations is that they are to some extent readable even without the software that interprets them. It is useful to distinguish them, at the highest level, from such unreadable data as images, audio, or text represented in an unreadable form. In the absence of appropriate interpretation software, it is reasonable to present subtypes of "text" to the user, while it is not reasonable to do so with most non-textual data. Such formatted textual data can be represented using subtypes of "text".
除了纯文本之外，还有许多格式可以表示所谓的“富文本”。许多这种表示法的一个有趣特征是，即使没有解释它们的软件，它们在某种程度上也是可读的。在最高层次上，将它们与图像、音频或以不可读形式表示的文本等不可读数据区分开来是很有用的。在没有合适的解释软件的情况下，向用户呈现“文本”的子类型是合理的，而对大多数非文本数据这样做是不合理的。这种格式化的文本数据可以使用“text”的子类型来表示。
A top-level type of "image" indicates that the content specifies one or more individual images. The subtype names the specific image format.
顶级类型的“图像”表示内容指定了一个或多个单独的图像。子类型命名特定的图像格式。
A top-level type of "audio" indicates that the content contains audio data. The subtype names the specific audio format.
顶级类型的“音频”表示内容包含音频数据。子类型命名特定的音频格式。
A top-level type of "video" indicates that the content specifies a time-varying-picture image, possibly with color and coordinated sound. The term 'video' is used in its most generic sense, rather than with reference to any particular technology or format, and is not meant to preclude subtypes such as animated drawings encoded compactly.
顶级类型的“视频”表示内容指定了一个随时间变化的图片图像，可能带有颜色和协调的声音。术语“视频”在其最一般的意义上使用，而不是指任何特定的技术或格式，并不意味着排除子类型，例如紧凑编码的动画图形。
Note that although in general the mixing of multiple kinds of media in a single body is discouraged [RFC2046], it is recognized that many video formats include a representation for synchronized audio and/or text, and this is explicitly permitted for subtypes of "video".
请注意，尽管通常不鼓励在一个主体中混合多种媒体[RFC2046]，但人们认识到，许多视频格式包括同步音频和/或文本的表示，这对于“视频”的子类型是明确允许的。
The "application" top-level type is to be used for discrete data that do not fit under any of the other type names, and particularly for data to be processed by some type of application program. This is information that must be processed by an application before it is viewable or usable by a user. Expected uses for the "application" type name include but are not limited to file transfer, spreadsheets, presentations, scheduling data, and languages for "active" (computational) material. (The last, in particular, can pose security problems that must be understood by implementors. The "application/postscript" media type registration in [RFC2046] provides a good example of how to handle these issues.)
“应用程序”顶级类型用于不适合任何其他类型名称的离散数据，特别是用于由某些类型的应用程序处理的数据。这是应用程序必须处理的信息，用户才能查看或使用这些信息。“应用程序”类型名称的预期用途包括但不限于文件传输、电子表格、演示文稿、计划数据和“活动”（计算）材料的语言。（尤其是最后一个问题可能会带来安全问题，实施者必须理解。在[RFC2046]中的“应用程序/postscript”媒体类型注册提供了一个处理这些问题的好例子。）
For example, a meeting scheduler might define a standard representation for information about proposed meeting dates. An intelligent user agent would use this information to conduct a dialog with the user, and might then send additional material based on that dialog. More generally, there have been several "active" languages developed in which programs in a suitably specialized language are transported to a remote location and automatically run in the recipient's environment. Such applications may be defined as subtypes of the "application" top-level type.
例如，会议调度器可能会为有关建议会议日期的信息定义标准表示形式。智能用户代理将使用此信息与用户进行对话，然后根据该对话发送其他材料。更一般地说，已经开发了几种“主动”语言，其中使用适当专门语言的程序被传输到远程位置，并在接收者的环境中自动运行。此类应用程序可以定义为“应用程序”顶级类型的子类型。
The subtype of "application" will often either be the name or include part of the name of the application for which the data are intended. This does not mean, however, that any application program name may simply be used freely as a subtype of "application"; the subtype needs to be registered.
“应用程序”的子类型通常是数据所针对的应用程序的名称或包含其部分名称。然而，这并不意味着任何应用程序名称都可以作为“应用程序”的子类型自由使用；需要注册子类型。
Multipart and message are composite types; that is, they provide a means of encapsulating zero or more objects, each one a separate media type.
Multipart和message是复合类型；也就是说，它们提供了一种封装零个或多个对象的方法，每个对象都是单独的媒体类型。
All subtypes of multipart and message MUST conform to the syntax rules and other requirements specified in [RFC2046] and amended by Section 3.5 of [RFC6532].
多部分和消息的所有子类型必须符合[RFC2046]中规定并经[RFC6532]第3.5节修订的语法规则和其他要求。
In some cases, a new media type may not "fit" under any currently defined top-level type names. Such cases are expected to be quite rare. However, if such a case does arise, a new type name can be defined to accommodate it. Definition of a new top-level type name MUST be done via a Standards Track RFC; no other mechanism can be used to define additional type names.
在某些情况下，新媒体类型可能不适合任何当前定义的顶级类型名称。这种情况预计相当罕见。但是，如果出现这种情况，可以定义一个新的类型名来适应它。必须通过标准跟踪RFC定义新的顶级类型名称；不能使用其他机制来定义其他类型名称。
XML in MIME [RFC3023] defined the first such augmentation to the media type definition to additionally specify the underlying structure of that media type. To quote:
MIME[RFC3023]中的XML定义了对媒体类型定义的第一个此类扩充，以另外指定该媒体类型的底层结构。引述：
This document also standardizes a convention (using the suffix '+xml') for naming media types ... when those media types represent XML MIME (Multipurpose Internet Mail Extensions) entities.
本文档还标准化了命名媒体类型的约定（使用后缀“+xml”）。。。当这些媒体类型表示XML MIME（多用途Internet邮件扩展）实体时。
That is, it specified a suffix (in that case, "+xml") to be appended to the base subtype name.
也就是说，它指定了一个后缀（在这种情况下为“+xml”）附加到基子类型名称。
Since this was published, the de facto practice has arisen for using this suffix convention for other well-known structuring syntaxes. In particular, media types have been registered with suffixes such as "+der", "+fastinfoset", and "+json". This specification formalizes this practice and sets up a registry for structured type name suffixes.
自从这本书出版以来，事实上已经出现了将这个后缀约定用于其他著名的结构化语法的做法。特别是，媒体类型已注册为后缀，如“+der”、“+fastinfoset”和“+json”。本规范将此实践形式化，并为结构化类型名称后缀设置注册表。
The primary guideline for whether a structured type name suffix is registrable is that it be described by a readily available description, preferably within a document published by an established standards-related organization, and for which there's a reference that can be used in a Normative References section of an RFC.
关于结构化类型名称后缀是否可注册的主要指导原则是，应通过现成的描述对其进行描述，最好是在已建立的标准相关组织发布的文件中进行描述，并且RFC的规范性引用部分中可使用该文档的引用。
Media types that make use of a named structured syntax SHOULD use the appropriate registered "+suffix" for that structured syntax when they are registered. By the same token, media types MUST NOT be given names incorporating suffixes for structured syntaxes they do not actually employ. "+suffix" constructs for as-yet unregistered structured syntaxes SHOULD NOT be used, given the possibility of conflicts with future suffix definitions.
使用命名结构化语法的媒体类型在注册时应为该结构化语法使用相应的注册“+后缀”。出于同样的原因，媒体类型的名称不能包含它们实际上不使用的结构化语法的后缀。鉴于可能与将来的后缀定义冲突，不应使用尚未注册的结构化语法的“+后缀”构造。
In some cases, a single media type may have been widely deployed prior to registration under multiple names. In such cases, a preferred name MUST be chosen for the media type, and applications MUST use this to be compliant with the type's registration. However, a list of deprecated aliases by which the type is known MAY be supplied as additional information in order to assist applications in processing the media type properly.
在某些情况下，在以多个名称注册之前，可能已广泛部署了单一媒体类型。在这种情况下，必须为媒体类型选择一个首选名称，应用程序必须使用该名称以符合该类型的注册。但是，可以提供已知类型的不推荐别名列表作为附加信息，以帮助应用程序正确处理媒体类型。
Media types MAY elect to use one or more media type parameters, or some parameters may be automatically made available to the media type by virtue of being a subtype of a content type that defines a set of parameters applicable to any of its subtypes. In either case, the names, values, and meanings of any parameters MUST be fully specified when a media type is registered in the standards tree, and SHOULD be specified as completely as possible when media types are registered in the vendor or personal trees.
媒体类型可以选择使用一个或多个媒体类型参数，或者由于某些参数是定义适用于其任何子类型的一组参数的内容类型的子类型，因此某些参数可以自动提供给媒体类型。无论哪种情况，在标准树中注册介质类型时，必须完全指定任何参数的名称、值和含义，在供应商或个人树中注册介质类型时，应尽可能完整地指定这些参数。
Parameter names have the syntax as media type names and values:
参数名称的语法与媒体类型名称和值相同：
parameter-name = restricted-name
parameter-name = restricted-name
Note that this syntax is somewhat more restrictive than what is allowed by the ABNF in [RFC2045] and amended by [RFC2231].
请注意，该语法比[RFC2045]中ABNF所允许并由[RFC2231]修订的语法更具限制性。
Parameter names are case-insensitive and no meaning is attached to the order in which they appear. It is an error for a specific parameter to be specified more than once.
参数名称不区分大小写，并且它们的出现顺序没有任何意义。多次指定特定参数是错误的。
There is no defined syntax for parameter values. Therefore, registrations MUST specify parameter value syntax. Additionally, some transports impose restrictions on parameter value syntax, so care needs be taken to limit the use of potentially problematic syntaxes; e.g., pure binary valued parameters, while permitted in some protocols, are best avoided.
没有为参数值定义语法。因此，注册必须指定参数值语法。此外，一些传输对参数值语法施加了限制，因此需要注意限制潜在问题语法的使用；e、 例如，虽然某些协议允许使用纯二进制值参数，但最好避免使用。
Note that a protocol can impose further restrictions on parameter value syntax, depending on how it chooses to represent parameters. Both MIME [RFC2045] [RFC2231] and HTTP [RFC2045] [RFC5987] allow binary parameters as well as parameter values expressed in a specific charset, but other protocols may be less flexible.
请注意，协议可以对参数值语法施加进一步的限制，这取决于它选择如何表示参数。MIME[RFC2045][RFC2231]和HTTP[RFC2045][RFC5987]都允许使用二进制参数以及以特定字符集表示的参数值，但其他协议可能不太灵活。
New parameters SHOULD NOT be defined as a way to introduce new functionality in types registered in the standards tree, although new parameters MAY be added to convey additional information that does
不应将新参数定义为在标准树中注册的类型中引入新功能的方法，尽管可以添加新参数来传递额外的信息
not otherwise change existing functionality. An example of this would be a "revision" parameter to indicate a revision level of an external specification such as JPEG. Similar behavior is encouraged for media types registered in the vendor or personal trees, but is not required.
否则不会更改现有功能。例如，“修订”参数表示外部规范（如JPEG）的修订级别。对于在供应商或个人目录树中注册的媒体类型，鼓励采取类似的行为，但不是必需的。
Changes to parameters (including the introduction of new ones) is managed in the same manner as other changes to the media type; see Section 5.5.
参数更改（包括引入新参数）的管理方式与介质类型的其他更改相同；见第5.5节。
All registered media types MUST employ a single, canonical data format, regardless of registration tree.
无论注册树如何，所有注册的媒体类型都必须采用单一的规范数据格式。
A permanent and readily available public specification of the format for the media type MUST exist for all types registered in the standards tree. This specification MUST provide sufficient detail so that interoperability between independent implementations using the media type is possible. This specification MUST at a minimum be referenced by, if it is not actually included in, the media type registration proposal itself.
对于在标准树中注册的所有类型，必须存在媒体类型格式的永久且随时可用的公共规范。该规范必须提供足够的细节，以便使用媒体类型的独立实现之间的互操作性成为可能。如果媒体类型注册提案本身未包含本规范，则至少必须引用本规范。
The specifications of format and processing particulars may or may not be publicly available for media types registered in the vendor and personal trees. Such registrations are explicitly permitted to limit the information in the registration to which software and version produce or process such media types. As such, references to or inclusion of format specifications in registrations is encouraged but not required. Note, however, that the public availability of a meaningful specification will often make the difference between simply having a name reserved so that there are no conflicts with other uses and having the potential for other implementations of the media type and useful interoperation with them.
格式和处理细节的规范可能公开，也可能不公开，用于在供应商和个人目录树中注册的媒体类型。此类注册明确允许限制软件和版本生产或处理此类媒体类型的注册中的信息。因此，鼓励但不要求在注册中引用或包含格式规范。但是，请注意，有意义的规范的公共可用性通常会在保留名称以避免与其他用途发生冲突和可能实现媒体类型的其他实现以及与它们的有用互操作之间产生区别。
Some media types involve the use of patented technology. The registration of media types involving patented technology is specifically permitted. However, the restrictions set forth in BCP 79 [RFC3979] and BCP 78 [RFC5378] on the use of patented technology in IETF Standards Track protocols must be respected when the specification of a media type is part of a Standards Track protocol. In addition, other standards-related organizations making use of the standards tree may have their own rules regarding intellectual property that must be observed in their registrations.
一些媒体类型涉及专利技术的使用。特别允许注册涉及专利技术的媒体类型。但是，当媒体类型的规范是标准跟踪协议的一部分时，必须遵守BCP 79[RFC3979]和BCP 78[RFC5378]中规定的关于在IETF标准跟踪协议中使用专利技术的限制。此外，使用标准树的其他与标准相关的组织可能有自己的知识产权规则，这些规则必须在注册时遵守。
Intellectual Property Rights (IPR) disclosures for registrations in the vendor and personal trees are encouraged but not required.
鼓励但不要求在供应商和个人树木中披露注册的知识产权（IPR）。
Ideally, media types will be defined so they interoperate across as many systems and applications as possible. However, some media types will inevitably have problems interoperating across different platforms. Problems with different versions, byte ordering, and specifics of gateway handling can and will arise.
理想情况下，将定义媒体类型，以便它们能够跨尽可能多的系统和应用程序进行互操作。但是，某些媒体类型在跨不同平台的互操作中不可避免地会遇到问题。不同版本、字节顺序和网关处理细节的问题可能会出现，也将出现。
Universal interoperability of media types is not required, but known interoperability issues SHOULD be identified whenever possible. Publication of a media type does not require an exhaustive review of interoperability, and the interoperability considerations section is subject to continuing evaluation.
不需要介质类型的通用互操作性，但应尽可能确定已知的互操作性问题。媒体类型的发布不需要对互操作性进行详尽的审查，互操作性注意事项部分需要持续评估。
The recommendations in this subsection apply regardless of the registration tree involved.
本小节中的建议适用于任何涉及的注册树。
An analysis of security issues MUST be done for all types registered in the standards tree. A similar analysis for media types registered in the vendor or personal trees is encouraged but not required. However, regardless of what security analysis has or has not been done, all descriptions of security issues MUST be as accurate as possible regardless of registration tree. In particular, the security considerations MUST NOT state that there are "no security issues associated with this type". Security considerations for types in the vendor or personal tree MAY say that "the security issues associated with this type have not been assessed".
必须对标准树中注册的所有类型进行安全问题分析。鼓励但不要求对在供应商或个人目录树中注册的媒体类型进行类似的分析。但是，无论是否进行了安全性分析，无论注册树如何，所有安全性问题的描述都必须尽可能准确。特别是，安全注意事项不得声明“不存在与此类型相关的安全问题”。供应商或个人目录树中类型的安全注意事项可能表示“尚未评估与此类型相关的安全问题”。
There is absolutely no requirement that media types registered in any tree be secure or completely free from risks. Nevertheless, all known security risks MUST be identified in the registration of a media type, again regardless of registration tree.
绝对不要求在任何树中注册的媒体类型是安全的或完全没有风险的。尽管如此，所有已知的安全风险都必须在媒体类型的注册中识别出来，这与注册树无关。
The security considerations section of all registrations is subject to continuing evaluation and modification, and in particular MAY be extended by use of the "comments on media types" mechanism described in Section 5.4 below.
所有注册的“安全注意事项”部分将继续进行评估和修改，特别是可通过使用下文第5.4节所述的“媒体类型评论”机制进行扩展。
Some of the issues that need to be examined and described in a security analysis of a media type are:
在媒体类型的安全分析中需要检查和描述的一些问题包括：
o Complex media types may include provisions for directives that institute actions on a recipient's files or other resources. In many cases, provision is made for originators to specify arbitrary actions in an unrestricted fashion that may then have devastating effects. See the registration of the application/postscript media
o 复杂的媒体类型可能包括对收件人的文件或其他资源执行操作的指令的规定。在许多情况下，规定发起者以不受限制的方式指定可能产生毁灭性影响的任意行为。请参阅应用程序/postscript介质的注册
type in [RFC2046] for an example of such directives and how they can be described in a media type registration.
键入[RFC2046]以获取此类指令的示例，以及如何在媒体类型注册中描述这些指令。
o Any security analysis MUST state whether or not they employ such "active content"; if they do, they MUST state what steps have been taken, or MUST be taken by applications of the media type, to protect users of the media type from harm.
o 任何安全分析都必须说明他们是否使用这种“活动内容”；如果他们这样做，他们必须说明已经采取了什么步骤，或者媒体类型的应用程序必须采取什么步骤来保护媒体类型的用户不受伤害。
o Complex media types may include provisions for directives that institute actions that, while not directly harmful to the recipient, may result in disclosure of information that either facilitates a subsequent attack or else violates a recipient's privacy in some way. Again, the registration of the application/ postscript media type illustrates how such directives can be handled.
o 复杂的媒体类型可能包括指令规定，这些指令虽然不会直接伤害接收者，但可能导致信息泄露，从而促进后续攻击或以某种方式侵犯接收者的隐私。同样，应用程序/postscript媒体类型的注册说明了如何处理此类指令。
o A media type that employs compression may provide an opportunity for sending a small amount of data that, when received and evaluated, expands enormously to consume all of the recipient's resources. All media types SHOULD state whether or not they employ compression; if they do, they SHOULD discuss what steps need to be taken to avoid such attacks.
o 采用压缩的媒体类型可能会提供发送少量数据的机会，这些数据在接收和评估时会极大地扩展以消耗接收者的所有资源。所有媒体类型都应说明是否采用压缩；如果他们这样做了，他们应该讨论需要采取什么步骤来避免此类攻击。
o A media type might be targeted for applications that require some sort of security assurance but don't provide the necessary security mechanisms themselves. For example, a media type could be defined for storage of sensitive medical information that in turn requires external confidentiality and integrity protection services, or which is designed for use only within a secure environment. Types SHOULD always document whether or not they need such services in their security considerations.
o 媒体类型可能针对需要某种安全保证但本身不提供必要安全机制的应用程序。例如，可以为敏感医疗信息的存储定义一种媒体类型，而敏感医疗信息反过来又需要外部机密性和完整性保护服务，或者仅设计用于安全环境中。类型应始终在其安全注意事项中记录是否需要此类服务。
There are a number of additional requirements specific to the registration of XML media types. These requirements are specified in [RFC3023].
对于XML媒体类型的注册，还有许多特定的附加要求。[RFC3023]中规定了这些要求。
Some transports impose restrictions on the type of data they can carry. For example, Internet mail traditionally was limited to 7bit US-ASCII text. Encoding schemes are often used to work around such transport limitations.
一些传输对它们可以携带的数据类型施加限制。例如，互联网邮件传统上仅限于7位US-ASCII文本。编码方案通常用于解决此类传输限制。
It is therefore useful to note what sort of data a media type can consist of as part of its registration. An "encoding considerations" field is provided for this purpose. Possible values of this field are:
因此，注意作为注册的一部分，媒体类型可以包含哪些类型的数据是很有用的。为此提供了一个“编码注意事项”字段。此字段的可能值为：
7bit: The content of the media type consists solely of CRLF-delimited 7bit US-ASCII text.
7bit：媒体类型的内容仅由CRLF分隔的7bit US-ASCII文本组成。
8bit: The content of the media type consists solely of CRLF-delimited 8bit text.
8位：媒体类型的内容仅由CRLF分隔的8位文本组成。
binary: The content consists of an unrestricted sequence of octets.
二进制：内容由不受限制的八位字节序列组成。
framed: The content consists of a series of frames or packets without internal framing or alignment indicators. Additional out-of-band information is needed to interpret the data properly, including but not necessarily limited to knowledge of the boundaries between successive frames and knowledge of the transport mechanism. Note that media types of this sort cannot simply be stored in a file or transported as a simple stream of octets; therefore, such media types are unsuitable for use in many traditional protocols. A commonly used transport with framed encoding is the Real-time Transport Protocol, RTP. Additional rules for framed encodings defined for transport using RTP are given in [RFC4855].
框架：内容由一系列没有内部框架或对齐指示器的框架或数据包组成。需要额外的带外信息来正确解释数据，包括但不一定限于连续帧之间边界的知识和传输机制的知识。请注意，这类媒体类型不能简单地存储在文件中或作为简单的八位字节流传输；因此，这种媒体类型不适合在许多传统协议中使用。一种常用的帧编码传输协议是实时传输协议RTP。[RFC4855]中给出了为使用RTP传输定义的帧编码的其他规则。
Additional restrictions on 7bit and 8bit text are given in Section 4.1.1 of [RFC2046].
[RFC2046]第4.1.1节给出了7位和8位文本的其他限制。
In the asynchronous mail environment, where information on the capabilities of the remote mail agent is frequently not available to the sender, maximum interoperability is attained by restricting the media types used to those "common" formats expected to be widely implemented. This was asserted in the past as a reason to limit the number of possible media types, and resulted in a registration process with a significant hurdle and delay for those registering media types.
在异步邮件环境中，发送方通常无法获得有关远程邮件代理功能的信息，通过将使用的媒体类型限制为预期将广泛实施的“通用”格式，可以实现最大的互操作性。这在过去被认为是限制可能的媒体类型数量的一个理由，并导致注册过程中对那些注册媒体类型的人造成重大障碍和延迟。
However, the need for "common" media types does not require limiting the registration of new media types. If a limited set of media types is recommended for a particular application, that should be asserted by a separate applicability statement specific for the application and/or environment.
但是，对“通用”媒体类型的需求并不要求限制新媒体类型的注册。如果建议为特定应用程序提供一组有限的介质类型，则应通过针对该应用程序和/或环境的单独适用性声明来声明。
Therefore, universal support and implementation of a media type are NOT a requirement for registration. However, if a media type is
因此，通用支持和实现媒体类型不是注册的要求。但是，如果媒体类型为
explicitly intended for limited use, this MUST be noted in its registration. The "Restrictions on Usage" field is provided for this purpose.
明确用于有限用途，必须在其注册中注明。为此，提供了“使用限制”字段。
Media types registered in the standards tree by the IETF itself MUST be published as RFCs. RFC publication of vendor and personal media type registrations is allowed but not required. In all cases, the IANA will retain copies of all media type registrations and "publish" them as part of the media types registration tree itself.
IETF本身在标准树中注册的媒体类型必须作为RFC发布。允许但不要求RFC发布供应商和个人媒体类型注册。在所有情况下，IANA将保留所有媒体类型注册的副本，并将其作为媒体类型注册树本身的一部分“发布”。
As stated previously, standards-tree registrations for media types defined in documents produced by other standards-related organizations MUST be described by a formal standards specification produced by that organization. Additionally, any copyright on the registration template MUST allow the IANA to copy it into the IANA registry.
如前所述，其他标准相关组织编制的文件中定义的媒体类型的标准树注册必须由该组织编制的正式标准规范描述。此外，注册模板上的任何版权必须允许IANA将其复制到IANA注册中心。
Other than IETF registrations in the standards tree, the registration of a media type does not imply endorsement, approval, or recommendation by the IANA or the IETF or even certification that the specification is adequate. To become an IETF standard, a protocol or data object must go through the IETF standards process. While it provides additional assurances when it is appropriate, this is too difficult and too lengthy a process for the convenient registration of media types.
除了标准树中的IETF注册外，媒体类型的注册并不意味着IANA或IETF的认可、批准或建议，甚至不意味着证明该规范是充分的。要成为IETF标准，协议或数据对象必须经过IETF标准过程。虽然它在适当的时候提供了额外的保证，但这对于方便地注册媒体类型来说太困难、太长。
The standards tree exists for media types that do require a substantive review and approval process in a recognized standards-related organization. The vendor and personal trees exist for those media types that do not require such a process. It is expected that applicability statements for particular applications will be published from time to time in the IETF, recommending implementation of, and support for, media types that have proven particularly useful in those contexts.
标准树适用于在公认的标准相关组织中确实需要实质性审查和批准流程的媒体类型。对于不需要此过程的媒体类型，存在供应商和个人树。预计IETF将不时发布特定应用的适用性声明，建议实施和支持在这些环境中证明特别有用的媒体类型。
As discussed above, registration of a top-level type requires Standards Action in the IETF and, hence, the publication of a RFC on the Standards Track.
如上所述，顶级类型的注册需要在IETF中采取标准行动，因此需要在标准轨道上发布RFC。
Media type registrations can specify how applications should interpret fragment identifiers (specified in Section 3.5 of [RFC3986]) associated with the media type.
媒体类型注册可以指定应用程序应如何解释与媒体类型关联的片段标识符（在[RFC3986]第3.5节中指定）。
Media types are encouraged to adopt fragment identifier schemes that are used with semantically similar media types. In particular, media types that use a named structured syntax with a registered "+suffix" MUST follow whatever fragment identifier rules are given in the structured syntax suffix registration.
鼓励媒体类型采用与语义相似的媒体类型一起使用的片段标识符方案。特别是，使用带注册“+后缀”的命名结构化语法的媒体类型必须遵循结构化语法后缀注册中给出的任何片段标识符规则。
Various sorts of optional information SHOULD be included in the specification of a media type if it is available:
媒体类型规范中应包含各种可选信息（如果可用）：
o Magic number(s) (length, octet values). Magic numbers are byte sequences that are always present at a given place in the file and thus can be used to identify entities as being of a given media type.
o 幻数（长度、八位字节值）。幻数是始终存在于文件中给定位置的字节序列，因此可用于将实体标识为给定媒体类型。
o File name extension(s) commonly used on one or more platforms to indicate that some file contains a given media type.
o 一个或多个平台上常用的文件扩展名，用于指示某些文件包含给定的媒体类型。
o Mac OS File Type code(s) (4 octets) used to label files containing a given media type. Some discussion of Macintosh file type codes and their purpose can be found in [MacOSFileTypes].
o Mac OS文件类型代码（4个八位字节），用于标记包含给定媒体类型的文件。有关Macintosh文件类型代码及其用途的一些讨论，请参见[MacOSFileTypes]。
In the case of a registration in the standards tree, this additional information MAY be provided in the formal specification of the media type format. It is suggested that this be done by incorporating the IANA media type registration form into the format specification itself.
在标准树中注册的情况下，可在媒体类型格式的正式规范中提供此附加信息。建议通过将IANA媒体类型注册表合并到格式规范本身中来实现这一点。
The media type registration procedure is not a formal standards process, but rather an administrative procedure intended to allow community comment and sanity checking without excessive time delay.
媒体类型的注册程序不是一个正式的标准程序，而是一个行政程序，旨在允许社区评论和健全性检查，而无需过多的时间延迟。
Normal IETF processes need to be followed for all IETF registrations in the standards tree. The posting of an Internet Draft is a necessary first step, followed by posting to the media-types@iana.org list as discussed below.
标准树中的所有IETF注册都需要遵循正常的IETF流程。在互联网上发布草稿是必要的第一步，然后再向媒体发布-types@iana.org列表如下所述。
Notice of a potential media type registration in the standards tree SHOULD be sent to the media-types@iana.org mailing list for review. This mailing list has been established for the purpose of reviewing proposed media and access types. Registrations in other trees MAY be sent to the list for review as well; doing so is entirely OPTIONAL, but is strongly encouraged.
应向介质发送标准树中可能的介质类型注册通知-types@iana.org邮件列表供审查。建立此邮件列表的目的是审查建议的媒体和访问类型。其他树的注册也可以发送到列表中进行审查；这样做完全是可选的，但强烈鼓励这样做。
The intent of the public posting to this list is to solicit comments and feedback on the choice of type/subtype name, the unambiguity of the references with respect to versions and external profiling information, and a review of any interoperability or security considerations. The submitter may submit a revised registration proposal or abandon the registration completely and at any time.
公开发布到此列表的目的是就类型/子类型名称的选择、版本和外部分析信息引用的明确性以及任何互操作性或安全考虑事项的审查征求意见和反馈。提交人可随时提交修改后的注册建议书或完全放弃注册。
Media types registered in the standards tree by the IETF itself MUST be reviewed and approved by the IESG as part of the normal standards process. Standards-tree registrations by recognized standards-related organizations as well as registrations in the vendor and personal trees are submitted directly to the IANA, unless other arrangements were made as part of a liaison agreement. In either case, posting the registration to the media-types@iana.org list for review prior to submission is strongly encouraged.
IETF本身在标准树中注册的媒体类型必须由IESG审查和批准，作为正常标准过程的一部分。由公认的标准相关组织进行的标准树注册以及供应商和个人树的注册直接提交给IANA，除非作为联络协议的一部分做出了其他安排。无论哪种情况，都可以将注册信息发布到媒体上-types@iana.org强烈鼓励在提交前对清单进行审查。
Registration requests can be sent to iana@iana.org. A web form for registration requests is also available:
注册申请可发送至iana@iana.org. 还提供了注册请求的web表单：
http://www.iana.org/form/media-types
http://www.iana.org/form/media-types
Standardization processes often take considerable time to complete. In order to facilitate prototyping and testing, it is often helpful to assign identifiers, including but not limited to media types, early in the process. This way, identifiers used during standards development can remain unchanged once the process is complete, and implementations and documentation do not have to be updated.
标准化过程通常需要相当长的时间才能完成。为了便于原型设计和测试，在过程的早期分配标识符（包括但不限于媒体类型）通常很有帮助。这样，标准开发过程中使用的标识符可以在过程完成后保持不变，并且实现和文档不必更新。
Accordingly, a provisional registration process is provided to support early assignment of media type names in the standards tree. A provisional registration MAY be submitted to IANA for standards-tree types. The only required fields in such registrations are the media type name and contact information (including the standards-related organization name).
因此，提供临时注册过程以支持在标准树中提前分配媒体类型名称。可向IANA提交标准树类型的临时注册。此类注册中唯一需要的字段是媒体类型名称和联系信息（包括与标准相关的组织名称）。
Upon receipt of a provisional registration, IANA will check the name and contact information, then publish the registration in a distinct publicly visible provisional registration list.
收到临时注册后，IANA将检查姓名和联系信息，然后将注册发布在一个清晰可见的临时注册列表中。
Provisional registrations MAY be updated or abandoned at any time. When the registration is abandoned, the media type is no longer registered in any sense; it can subsequently be registered just like any other unassigned media type name.
临时注册可随时更新或放弃。当注册被放弃时，媒体类型在任何意义上都不再注册；它随后可以像任何其他未分配的媒体类型名称一样进行注册。
With the exception of provisional standards-tree registrations, registrations submitted to the IANA will be passed on to the media types reviewer. The media types reviewer, who is appointed by the IETF Applications Area Director(s), will review the registration to make sure it meets the requirements set forth in this document. Registrations that do not meet these requirements will be returned to the submitter for revision.
除临时标准树注册外，提交给IANA的注册将转交给媒体类型审查员。由IETF应用领域总监任命的媒体类型审查员将审查注册，以确保其符合本文件规定的要求。不符合这些要求的注册将返回给提交人进行修订。
Decisions made by the media types reviewer may be appealed to the IESG using the procedure specified in Section 6.5.4 of [RFC2026].
可使用[RFC2026]第6.5.4节规定的程序，对媒体类型审查员做出的决定向IESG提出上诉。
Once a media type registration has passed review, the IANA will register the media type and make the media type registration available to the community.
一旦媒体类型注册通过审核，IANA将注册媒体类型，并向社区提供媒体类型注册。
In the case of standards-tree registrations from other standards-related organizations, IANA will also check that the submitter is in fact a recognized standards-related organization. If the submitter is not currently recognized as such, the IESG will be asked to confirm their status. Recognition from the IESG MUST be obtained before a standards-tree registration can proceed.
对于来自其他标准相关组织的标准树注册，IANA还将检查提交者是否是公认的标准相关组织。如果提交人目前未被确认为提交人，将要求IESG确认其状态。在进行标准树注册之前，必须获得IESG的认可。
Comments on registered media types may be submitted by members of the community to the IANA at iana@iana.org. These comments will be reviewed by the media types reviewer and then passed on to the "owner" of the media type if possible. Submitters of comments may request that their comment be attached to the media type registration itself; if the IANA, in consultation with the media types reviewer, approves, the comment will be made accessible in conjunction with the type registration.
社区成员可通过以下方式向IANA提交注册媒体类型的评论：iana@iana.org. 这些评论将由媒体类型审阅者审阅，然后尽可能传递给媒体类型的“所有者”。评论提交人可要求将其评论附于媒体类型注册本身；如果IANA与媒体类型审核人协商批准，则评论将与类型注册一起提供。
Once a media type has been published by the IANA, the owner may request a change to its definition. The descriptions of the different registration trees above designate the "owners" of each type of registration. The same procedure that would be appropriate for the original registration request is used to process a change request.
IANA发布媒体类型后，所有者可以请求更改其定义。上述不同注册树的描述指定了每种注册类型的“所有者”。适用于原始注册申请的相同程序用于处理变更申请。
Media type registrations may not be deleted; media types that are no longer believed appropriate for use can be declared OBSOLETE by a change to their "intended use" field; such media types will be clearly marked in the lists published by the IANA.
不能删除媒体类型注册；通过更改“预期用途”字段，可以宣布不再适合使用的媒体类型为过时；IANA发布的列表中将明确标记此类媒体类型。
Significant changes to a media type's definition should be requested only when there are serious omissions or errors in the published specification. When review is required, a change request may be denied if it renders entities that were valid under the previous definition invalid under the new definition.
只有在发布的规范中存在严重遗漏或错误时，才应要求对媒体类型的定义进行重大更改。当需要审查时，如果变更请求使根据先前定义有效的实体在新定义下无效，则变更请求可能会被拒绝。
The owner of a media type may pass responsibility to another person or agency by informing the IANA; this can be done without discussion or review.
媒体类型的所有者可以通过通知IANA将责任转移给另一个人或机构；这可以在不进行讨论或审查的情况下完成。
The IESG may reassign responsibility for a media type. The most common case of this will be to enable changes to be made to types where the author of the registration has died, moved out of contact, or is otherwise unable to make changes that are important to the community.
IESG可以重新分配媒体类型的责任。最常见的情况是允许对注册作者已去世、失去联系或无法对社区进行重要更改的类型进行更改。
Type name:
类型名称：
Subtype name:
子类型名称：
Required parameters:
所需参数：
Optional parameters:
可选参数：
Encoding considerations:
编码注意事项：
Security considerations:
安全考虑：
Interoperability considerations:
互操作性注意事项：
Published specification:
已发布的规范：
Applications that use this media type:
使用此媒体类型的应用程序：
Fragment identifier considerations:
片段标识符注意事项：
Additional information:
其他信息：
Deprecated alias names for this type: Magic number(s): File extension(s): Macintosh file type code(s):
此类型的不推荐别名：幻数：文件扩展名：Macintosh文件类型代码：
Person & email address to contact for further information:
联系人和电子邮件地址，以获取更多信息：
Intended usage:
预期用途：
(One of COMMON, LIMITED USE, or OBSOLETE.)
（常用的、有限的或过时的。）
Restrictions on usage:
使用限制：
(Any restrictions on where the media type can be used go here.)
（有关媒体类型可使用位置的任何限制，请转到此处。）
Author:
作者：
Change controller:
更改控制器：
Provisional registration? (standards tree only):
临时登记？（仅限标准树）：
(Any other information that the author deems interesting may be added below this line.)
（作者认为有趣的任何其他信息可添加在此行下方。）
"N/A", written exactly that way, can be used in any field if desired to emphasize the fact that it does not apply or that the question was not omitted by accident. Do not use 'none' or other words that could be mistaken for a response.
正是这样写的“N/A”可以用在任何领域，如果想要强调它不适用或者这个问题不是偶然遗漏的。不要使用“无”或其他可能被误认为是响应的词语。
Limited-use media types should also note in the applications list whether or not that list is exhaustive.
有限使用介质类型还应在应用程序列表中注明该列表是否详尽。
Someone wishing to define a "+suffix" name for a structured syntax for use with a new media type registration SHOULD:
希望为新媒体类型注册使用的结构化语法定义“+后缀”名称的人应：
1. Check IANA's registry of media type name suffixes to see whether or not there is already an entry for that well-defined structured syntax.
1. 检查IANA的媒体类型名称后缀注册表，查看是否已经存在该定义良好的结构化语法的条目。
2. If there is no entry for their suffix scheme, fill out the template (specified in Section 6.2) and include that with the media type registration. The template may be contained in an Internet Draft, alone or as part of some other protocol specification. The template may also be submitted in some other form (as part of another document or as a stand-alone document), but the contents will be treated as an "IETF Contribution" under the guidelines of BCP 78 [RFC5378].
2. 如果没有后缀方案条目，请填写模板（第6.2节中规定），并将其与媒体类型注册一起包含。该模板可以单独包含在互联网草案中，也可以作为某些其他协议规范的一部分。模板也可以以其他形式提交（作为其他文件的一部分或作为独立文件），但根据BCP 78[RFC5378]的指南，其内容将被视为“IETF贡献”。
3. Send a copy of the template or a pointer to the containing document (with specific reference to the section with the template) to the mailing list media-types@iana.org, requesting
3. 将模板副本或指向包含文档的指针（具体参考带有模板的部分）发送到邮件列表介质-types@iana.org，请求
review. This may be combined with a request to review the media type registration. Allow a reasonable time for discussion and comments.
回顾这可能与审查媒体类型注册的请求相结合。留出合理的时间进行讨论和评论。
4. Respond to review comments and make revisions to the proposed registration as needed to bring it into line with the guidelines given in this document.
4. 回应审查意见，并根据需要对拟议注册进行修订，使其符合本文件中给出的指南。
5. Submit the (possibly updated) registration template (or pointer to the document containing it) to IANA at iana@iana.org.
5. 将（可能更新的）注册模板（或指向包含该模板的文档的指针）提交给IANA，地址为iana@iana.org.
Upon receipt of a structured syntax suffix registration request,
收到结构化语法后缀注册请求后，
1. IANA checks the submission for completeness; if sections are missing or citations are not correct, IANA rejects the registration request.
1. IANA检查提交文件的完整性；如果章节缺失或引用不正确，IANA将拒绝注册请求。
2. IANA checks the current registry for an entry with the same name; if such a registry exists, IANA rejects the registration request.
2. IANA检查当前注册表中是否有同名条目；如果存在这样的注册表，IANA将拒绝注册请求。
3. IANA requests Expert Review of the registration request against the corresponding guidelines.
3. IANA要求根据相应指南对注册申请进行专家审查。
4. The Designated Expert may request additional review or discussion, as necessary.
4. 必要时，指定专家可要求进行额外审查或讨论。
5. If Expert Review recommends registration, IANA adds the registration to the appropriate registry.
5. 如果专家评审建议注册，IANA会将注册添加到相应的注册表中。
The initial registry content specification [RFC6839] provides examples of structured syntax suffix registrations.
初始注册表内容规范[RFC6839]提供了结构化语法后缀注册的示例。
Registrations may be updated in each registry by the same mechanism as required for an initial registration. In cases where the original definition of the scheme is contained in an IESG-approved document, update of the specification also requires IESG approval.
每个登记处的登记可以按照初始登记所需的相同机制进行更新。如果计划的原始定义包含在IESG批准的文件中，则规范的更新也需要IESG批准。
This template describes the fields that must be supplied in a structured syntax suffix registration request:
此模板描述了结构化语法后缀注册请求中必须提供的字段：
Name Full name of the well-defined structured syntax.
Name定义良好的结构化语法的全名。
+suffix Suffix used to indicate conformance to the syntax.
+后缀用于表示符合语法的后缀。
References Include full citations for all specifications necessary to understand the structured syntax.
参考文献包括理解结构化语法所需的所有规范的完整引用。
Encoding considerations General guidance regarding encoding considerations for any type employing this syntax should be given here. The same requirements for media type encoding considerations given in Section 4.8 apply here.
编码注意事项此处应给出关于使用此语法的任何类型的编码注意事项的一般指导。第4.8节中给出的媒体类型编码注意事项的相同要求适用于此处。
Interoperability considerations Any issues regarding the interoperable use of types employing this structured syntax should be given here. Examples would include the existence of incompatible versions of the syntax, issues combining certain charsets with the syntax, or incompatibilities with other types or protocols.
互操作性注意事项关于使用这种结构化语法的类型的互操作使用的任何问题都应该在这里给出。示例包括存在语法的不兼容版本、将某些字符集与语法相结合的问题，或者与其他类型或协议不兼容。
Fragment identifier considerations Generic processing of fragment identifiers for any type employing this syntax should be described here.
片段标识符注意事项此处应描述使用此语法的任何类型的片段标识符的一般处理。
Security considerations Security considerations shared by media types employing this structured syntax must be specified here. The same requirements for media type security considerations given in Section 4.6 apply here, with the exception that the option of not assessing the security considerations is not available for suffix registrations.
安全注意事项使用此结构化语法的媒体类型共享的安全注意事项必须在此处指定。第4.6节中给出的媒体类型安全注意事项的相同要求适用于此处，但不评估安全注意事项的选项不适用于后缀注册。
Contact Person (including contact information) to contact for further information.
联系人（包括联系信息）联系以获取更多信息。
Author/Change controller. Person (including contact information) authorized to change this suffix registration.
作者/更改控制器。有权更改此后缀注册的人员（包括联系信息）。
Security requirements for both media type and media type suffix registrations are discussed in Section 4.6.
第4.6节讨论了媒体类型和媒体类型后缀注册的安全要求。
The purpose of this document is to define IANA registries for media types and structured syntax suffixes as well as the procedures for managing these registries. Additionally, this document requires IANA to maintain a list of standards-related organizations for which the IESG has approved media type registrations in the standards tree.
本文档的目的是为媒体类型和结构化语法后缀定义IANA注册表，以及管理这些注册表的过程。此外，本文件要求IANA在标准树中维护IESG已批准媒体类型注册的标准相关组织列表。
The existing media type registry has been extended to include a section for provisional registrations. Only standards-tree registrations are allowed in the standards tree and only at the request of an organization on the IANA list of standards-related organizations. See Section 5.2.1 for additional information on provisional registrations.
现有的媒体类型注册表已扩展为包含临时注册部分。标准树中仅允许标准树注册，并且仅在IANA标准相关组织列表中的组织提出请求时才允许注册。有关临时注册的更多信息，请参见第5.2.1节。
IANA has also added the following note at the top of the provisional registry:
IANA还在临时登记册顶部添加了以下注释：
This registry, unlike some other provisional IANA registries, is only for temporary use. Entries in this registry are either finalized and moved to the main media types registry, or are abandoned and deleted. Entries in this registry are suitable for use for development and test purposes only.
与其他一些临时IANA注册不同，该注册仅用于临时用途。此注册表中的条目要么被最终确定并移动到主媒体类型注册表，要么被放弃并删除。此注册表中的条目仅适用于开发和测试目的。
The structured syntax name suffix registry has been created as follows:
已按如下方式创建结构化语法名称后缀注册表：
o The name is the "Structured Syntax Suffix" registry.
o 该名称是“结构化语法后缀”注册表。
o The registration process is specified in Section 6.
o 第6节规定了注册流程。
o The information required for a registry entry as well as the entry format are specified in Section 6.2.
o 第6.2节规定了注册表条目所需的信息以及条目格式。
o The initial content of the registry is specified in [RFC6839].
o 注册表的初始内容在[RFC6839]中指定。
Entries in both the media type and structured suffix registries will be annotated by IANA with both the original registration date as well as the date of the most recent update to the entry. Registrations made prior to the implementation of this specification may, if necessary, be marked as such, rather than with a specific date.
IANA将对媒体类型和结构化后缀注册中的条目进行注释，注明原始注册日期以及条目的最新更新日期。如有必要，在实施本规范之前进行的注册可标记为注册，而非特定日期。
Since registration entries can be updated multiple times, IANA will also maintain the history of changes to each registration in such a way that the state of the registration at any given time can be determined.
由于注册条目可以多次更新，IANA还将维护每次注册的变更历史，以便能够确定任何给定时间的注册状态。
Finally, per this document, IANA has created a new email address, media-types@iana.org, for the media type review list, which replaces the ietf-types@iana.org address specified in RFC 4288. ietf-types@iana.org has been retained as an alias.
最后，根据本文档，IANA创建了一个新的电子邮件地址media-types@iana.org，用于替代ietf的介质类型审查列表-types@iana.orgRFC 4288中指定的地址。ietf-types@iana.org已保留为别名。
The current authors would like to acknowledge their debt to the late Dr. Jon Postel, whose general model of IANA registration procedures and specific contributions shaped the predecessors of this document [RFC2048] [RFC4288]. We hope that the current version is one with which he would have agreed but, as it is impossible to verify that agreement, we have regretfully removed his name as a co-author.
目前的作者要感谢已故的Jon Postel博士，他的IANA注册程序的一般模型和具体贡献形成了本文件的前身[RFC2048][RFC4288]。我们希望目前的版本是他本会同意的版本，但由于无法核实这一协议，我们遗憾地删除了他作为合著者的姓名。
Randy Bush, Francis Dupont, Bjoern Hoehrmann, Barry Leiba, Murray Kucherawy, Alexey Melnikov, S. Moonesamy, Mark Nottingham, Tom Petch, Peter Saint-Andre, and Jeni Tennison provided many helpful review comments and suggestions.
兰迪·布什、弗朗西斯·杜邦、比约恩·霍尔曼、巴里·莱巴、默里·库奇拉维、阿列克谢·梅尔尼科夫、S.穆内萨米、马克·诺丁汉、汤姆·佩奇、彼得·圣安德烈和杰尼·坦尼森提供了许多有用的评论和建议。
[RFC2045] Freed, N. and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies", RFC 2045, November 1996.
[RFC2045]Freed，N.和N.Borenstein，“多用途Internet邮件扩展（MIME）第一部分：Internet邮件正文格式”，RFC 20451996年11月。
[RFC2046] Freed, N. and N. Borenstein, "Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types", RFC 2046, November 1996.
[RFC2046]Freed，N.和N.Borenstein，“多用途Internet邮件扩展（MIME）第二部分：媒体类型”，RFC 20461996年11月。
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2119]Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，1997年3月。
[RFC2978] Freed, N. and J. Postel, "IANA Charset Registration Procedures", BCP 19, RFC 2978, October 2000.
[RFC2978]Freed，N.和J.Postel，“IANA字符集注册程序”，BCP 19，RFC 2978，2000年10月。
[RFC3023] Murata, M., St. Laurent, S., and D. Kohn, "XML Media Types", RFC 3023, January 2001.
[RFC3023]Murata，M.，St.Laurent，S.，和D.Kohn，“XML媒体类型”，RFC 3023，2001年1月。
[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO 10646", STD 63, RFC 3629, November 2003.
[RFC3629]Yergeau，F.，“UTF-8，ISO 10646的转换格式”，STD 63，RFC 3629，2003年11月。
[RFC3979] Bradner, S., "Intellectual Property Rights in IETF Technology", BCP 79, RFC 3979, March 2005.
[RFC3979]Bradner，S.，“IETF技术中的知识产权”，BCP 79，RFC 3979，2005年3月。
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform Resource Identifier (URI): Generic Syntax", STD 66, RFC 3986, January 2005.
[RFC3986]Berners Lee，T.，Fielding，R.，和L.Masinter，“统一资源标识符（URI）：通用语法”，STD 66，RFC 3986，2005年1月。
[RFC4855] Casner, S., "Media Type Registration of RTP Payload Formats", RFC 4855, February 2007.
[RFC4855]Casner，S.，“RTP有效负载格式的媒体类型注册”，RFC 48552007年2月。
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 5226, May 2008.
[RFC5226]Narten，T.和H.Alvestrand，“在RFCs中编写IANA注意事项部分的指南”，BCP 26，RFC 5226，2008年5月。
[RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", STD 68, RFC 5234, January 2008.
[RFC5234]Crocker，D.和P.Overell，“语法规范的扩充BNF:ABNF”，STD 68，RFC 5234，2008年1月。
[RFC5378] Bradner, S. and J. Contreras, "Rights Contributors Provide to the IETF Trust", BCP 78, RFC 5378, November 2008.
[RFC5378]Bradner，S.和J.Contreras，“IETF信托基金的权利出资人”，BCP 78，RFC 5378，2008年11月。
[RFC6532] Yang, A., Steele, S., and N. Freed, "Internationalized Email Headers", RFC 6532, February 2012.
[RFC6532]Yang，A.，Steele，S.，和N.Freed，“国际化电子邮件标题”，RFC 6532，2012年2月。
[RFC6657] Melnikov, A. and J. Reschke, "Update to MIME regarding "charset" Parameter Handling in Textual Media Types", RFC 6657, July 2012.
[RFC6657]Melnikov，A.和J.Reschke，“关于文本媒体类型中“字符集”参数处理的MIME更新”，RFC 6657，2012年7月。
[RFC6839] Hansen, T. and A. Melnikov, "Additional Media Type Structured Syntax Suffixes", RFC 6839, January 2013.
[RFC6839]Hansen，T.和A.Melnikov，“其他媒体类型结构化语法后缀”，RFC 6839，2013年1月。
[MacOSFileTypes] Apple Computer, Inc., "Mac OS: File Type and Creator Codes, and File Formats", Apple Knowledge Base Article 55381, June 1993, <http://www.info.apple.com/kbnum/n55381>.
[MacOSFileTypes]Apple Computer，Inc.，“Mac OS:文件类型和创建者代码以及文件格式”，苹果知识库文章553811993年6月<http://www.info.apple.com/kbnum/n55381>.
[RFC2026] Bradner, S., "The Internet Standards Process -- Revision 3", BCP 9, RFC 2026, October 1996.
[RFC2026]Bradner，S.，“互联网标准过程——第3版”，BCP 9，RFC 2026，1996年10月。
[RFC2048] Freed, N., Klensin, J., and J. Postel, "Multipurpose Internet Mail Extensions (MIME) Part Four: Registration Procedures", BCP 13, RFC 2048, November 1996.
[RFC2048]Freed，N.，Klensin，J.和J.Postel，“多用途互联网邮件扩展（MIME）第四部分：注册程序”，BCP 13，RFC 2048，1996年11月。
[RFC2231] Freed, N. and K. Moore, "MIME Parameter Value and Encoded Word Extensions: Character Sets, Languages, and Continuations", RFC 2231, November 1997.
[RFC2231]Freed，N.和K.Moore，“MIME参数值和编码字扩展：字符集、语言和连续体”，RFC 22311997年11月。
[RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.
[RFC2616]菲尔丁，R.，盖蒂斯，J.，莫卧儿，J.，弗莱斯蒂克，H.，马斯特，L.，利奇，P.，和T.伯纳斯李，“超文本传输协议——HTTP/1.1”，RFC 2616，1999年6月。
[RFC4288] Freed, N. and J. Klensin, "Media Type Specifications and Registration Procedures", BCP 13, RFC 4288, December 2005.
[RFC4288]Freed，N.和J.Klensin，“介质类型规范和注册程序”，BCP 13，RFC 4288，2005年12月。
[RFC5987] Reschke, J., "Character Set and Language Encoding for Hypertext Transfer Protocol (HTTP) Header Field Parameters", RFC 5987, August 2010.
[RFC5987]Reschke，J.，“超文本传输协议（HTTP）头字段参数的字符集和语言编码”，RFC 5987，2010年8月。
[RFC6648] Saint-Andre, P., Crocker, D., and M. Nottingham, "Deprecating the "X-" Prefix and Similar Constructs in Application Protocols", BCP 178, RFC 6648, June 2012.
[RFC6648]圣安德烈，P.，克罗克，D.，和M.诺丁汉，“反对应用协议中的“X-”前缀和类似结构”，BCP 178，RFC 6648，2012年6月。
A number of media types with unfaceted subtype names, registered prior to 1996, would, if registered under the guidelines in this document, be given a faceted name and placed into either the vendor or personal trees. Reregistration of those types to reflect the appropriate trees is encouraged but not required. Ownership and change control principles outlined in this document apply to those types as if they had been registered in the trees described above.
如果根据本文件中的指南进行注册，1996年之前注册的许多具有非固定子类型名称的媒体类型将被赋予一个刻面名称，并放置在供应商树或个人树中。鼓励重新登记这些类型，以反映适当的树木，但不是必需的。本文件中概述的所有权和变更控制原则适用于这些类型，如同它们已在上述树木中注册一样。
From time to time there may also be cases where a media type with an unfaceted subtype name has been widely deployed without being registered. (Note that this includes subtype names beginning with the "x-" prefix.) If possible, such a media type SHOULD be reregistered with a proper faceted subtype name, possibly using a deprecated alias to identify the original name (see Section 4.2.9). However, if this is not possible, the type can, subject to approval by both the media types reviewer and the IESG, be registered in the proper tree with its unfaceted name.
有时也可能出现这样的情况，即未注册子类型名称的媒体类型已被广泛部署。（请注意，这包括以“x-”前缀开头的子类型名称。）如果可能，应使用正确的刻面子类型名称重新注册此类媒体类型，可能使用不推荐的别名来标识原始名称（请参阅第4.2.9节）。但是，如果这是不可能的，则该类型可以在媒体类型审阅者和IESG的批准下，以其未附加的名称在适当的树中注册。
o Suffixes to indicate the use of a particular structured syntax are now fully specified and a suffix registration process has been defined.
o 现在已经完全指定了表示使用特定结构化语法的后缀，并定义了后缀注册过程。
o Registration of widely deployed unregistered unfaceted type names in the vendor or personal trees is now allowed, subject to approval by the media types reviewer and the IESG.
o 现在允许在供应商或个人目录树中注册广泛部署的未注册的非固定类型名称，但需得到媒体类型审查员和IESG的批准。
o The standards-tree registration process has been revised to include Expert Review and generalized to address cases like media types in non-IETF stream documents.
o 对标准树注册过程进行了修订，包括专家审查，并对其进行了推广，以解决非IETF流文档中的媒体类型等情况。
o A field for fragment identifiers has been added to the registration template and brief directions for specifying fragment identifiers have been added.
o 已将片段标识符字段添加到注册模板中，并添加了用于指定片段标识符的简要说明。
o The specification requirements for personal-tree registrations have been changed to be the same as those for the vendor tree. The text has been changed to encourage (but not require) specification availability.
o 个人树注册的规范要求已更改为与供应商树的规范要求相同。文本已更改，以鼓励（但不要求）规范可用性。
o The process for defining additional trees has been clarified to state that an IETF Standards Action is required.
o 定义额外树的过程已经澄清，以说明需要IETF标准行动。
o Widely deployed types with "x-" names can now be registered as an exception in the vendor tree.
o 使用“x-”名称广泛部署的类型现在可以在供应商树中注册为异常。
o The requirements on changes to registrations have been loosened so minor changes are easier to make.
o 对注册变更的要求已经放宽，因此小的变更更容易进行。
o The registration process has been completely restructured so that with the exception of IETF-generated types in the standards tree, all requests are processed by IANA and not the IESG.
o 注册过程已经完全重组，因此除了标准树中IETF生成的类型外，所有请求都由IANA而不是IESG处理。
o A provisional registration process has been added for early assignment of types in the standards tree.
o 已添加临时注册过程，以便在标准树中提前分配类型。
o Many editorial changes have been made throughout the document to make the requirements and processes it describes clearer and easier to follow.
o 在整个文档中进行了许多编辑性修改，以使其描述的要求和过程更清晰、更易于遵循。
o The ability to specify a list of deprecated aliases for a media type has been added.
o 添加了为媒体类型指定不推荐使用的别名列表的功能。
o Types with names beginning with "x-" are no longer considered to be members of the unregistered "x." tree. As with any unfaceted type, special procedures have been added to allow registration of such types in an appropriate tree.
o 名称以“x-”开头的类型不再被视为未注册的“x”树的成员。与任何非固定类型一样，添加了特殊程序，以允许在适当的树中注册此类类型。
o Changes to a type registered by a third party may now be made by the designated change controller even if that isn't the vendor or organization that created the type. However, the vendor or organization may elect to assert ownership and change controller over the type at any time.
o 对第三方注册的类型的更改现在可以由指定的更改控制器进行，即使该控制器不是创建该类型的供应商或组织。但是，供应商或组织可以选择在任何时候声明所有权并更改该类型的控制器。
o Limited-use media types are now asked to note whether or not the supplied list of applications employing the media type is exhaustive.
o 现在要求限制使用的介质类型注意所提供的使用该介质类型的应用程序列表是否详尽无遗。
o The ABNF for media type names has been further restricted to require that names begin with an alphanumeric character.
o 介质类型名称的ABNF已进一步限制为要求名称以字母数字字符开头。
o Mailing list review is no longer required prior to registration of media types. Additionally, the address associated with the media type review mailing list has been changed to media-types@iana.org.
o 在注册媒体类型之前，不再需要审查邮件列表。此外，与介质类型审阅邮件列表关联的地址已更改为介质-types@iana.org.
o The rules for text/* media types have been updated to reflect the changes specified in [RFC6657].
o 文本/*媒体类型的规则已更新，以反映[RFC6657]中指定的更改。
Authors' Addresses
作者地址
Ned Freed Oracle 800 Royal Oaks Monrovia, CA 91016-6347 USA
美国加利福尼亚州蒙罗维亚皇家橡树园800号，邮编91016-6347
EMail: ned+ietf@mrochek.com
EMail: ned+ietf@mrochek.com
John C. Klensin 1770 Massachusetts Ave, #322 Cambridge, MA 02140 USA
美国马萨诸塞州剑桥市322号马萨诸塞大道1770号约翰·C·克伦辛，邮编：02140
EMail: john+ietf@jck.com
EMail: john+ietf@jck.com
Tony Hansen AT&T Laboratories 200 Laurel Ave. Middletown, NJ 07748 USA
美国新泽西州米德尔顿劳雷尔大道200号托尼·汉森AT&T实验室，邮编：07748
EMail: tony+mtsuffix@maillennium.att.com
EMail: tony+mtsuffix@maillennium.att.com