Network Working Group T. Taylor Request for Comments: 4735 Nortel Category: Standards Track October 2006 Example Media Types for Use in Documentation Status of This Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited. Copyright Notice Copyright (C) The Internet Society (2006). Abstract This document is registration for the 'example' media type and 'example' subtypes within the standards tree. The 'example/*' and '*/example' media types are defined for documentation purposes only. 1. Introduction From time to time, documents created by the IETF or by other standards bodies show examples involving the use of media types, where the actual media type is not relevant. It would be useful in such cases to be able to show a media type whose illustrative role in the example is clear. In the worst case, this can be useful to debug implementations where the designer mistook the example for a requirement of the protocol concerned. To meet this need, this document registers the following media types: o the 'example' media type; o the 'application/example', 'audio/example', 'image/example', 'message/example', 'model/example', 'multipart/example', 'text/example', and 'video/example' media subtypes. It is suggested that compilers of illustrative examples involving media types in trees other than the standards tree might also incorporate the string "example" into their hypothetical media types. Taylor Standards Track [Page 1] RFC 4735 Example Media Types October 2006 2. Terminology 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]. 3. Registration of the 'example' Media Type This section registers the 'example' media type in accordance with the requirements of RFC 4288. Type name: example. Subtype name: any subtype may be used with the 'example' type. However, IANA MUST NOT register any subtypes for the 'example' media type. Required parameters: as invented by the user. Optional parameters: as invented by the user. Encoding considerations: as invented by the user. Security considerations: The 'example' media type is defined for use in documentation only. It MUST NOT be implemented. Its appearance in real code could lead to unpredictable results and therefore open up security holes. Interoperability considerations: Any attempt to negotiate or send the 'example' media type is bound to lead to interoperability problems. Published specification: this document. Applications that use this media type: as invented by the user. Additional information: Magic number(s): not applicable. File extension(s): not applicable. Macintosh file type code(s): not applicable. Person & email address to contact for further information: ietf-types@iana.org. Intended usage: LIMITED USE. Taylor Standards Track [Page 2] RFC 4735 Example Media Types October 2006 Restrictions on usage: This type is intended only for use in documents providing examples involving specification of some media type, where the actual media type used is irrelevant. Author: Internet Engineering Task Force Change controller: Internet Engineering Task Force 4. Registration of the 'application/example', 'audio/example', 'image/example', 'message/example', 'model/example', 'multipart/example', 'text/example', and 'video/example' Subtypes This section registers 'example' media subtypes in accordance with the requirements of RFC 4288. Type name: 'application', 'audio', 'image', 'message', 'model', 'multipart', 'text', and 'video'. Subtype name: 'example'. Required parameters: those required by the type and any others as invented by the user. Optional parameters: those offered by the type and any others as invented by the user. Encoding considerations: as invented by the user. Security considerations: The 'example' media subtypes are defined for use in documentation only. They MUST NOT be implemented. Their appearance in real code could lead to unpredictable results and therefore open up security holes. Interoperability considerations: Any attempt to negotiate or send one of these 'example' media subtypes is bound to lead to interoperability problems. Published specification: this document. Applications that use this media type: as invented by the user. Additional information: Magic number(s): not applicable. File extension(s): not applicable. Macintosh file type code(s): not applicable. Person & email address to contact for further information: ietf-types@iana.org. Taylor Standards Track [Page 3] RFC 4735 Example Media Types October 2006 Intended usage: LIMITED USE. Restrictions on usage: These subtypes are intended only for use in documents providing examples involving specification of some subtype of the given media type, where the actual subtype used is irrelevant. Author: Internet Engineering Task Force Change controller: Internet Engineering Task Force 5. Security Considerations The 'example' media type and subtypes are defined for use in documentation only. They MUST NOT be implemented. Any attempt to implement them in real code could lead to unpredictable results and thus potentially open up security holes. 6. IANA Considerations This document specifies and registers the 'example' media type and the 'application/example', 'audio/example', 'image/example', 'message/example', 'model/example', 'multipart/example', 'text/example', and 'video/example' subtypes. 7. Acknowledgements This document sprang from Magnus Westerland's expression of need and Rod Walsh's support and suggestions for generalization. Warnings against implementation in the Security Considerations and Interoperability Considerations sections and the 'multipart/example' subtype were added at John Klensin's suggestion. Some editing touchups and strengthening of the language in the Security Considerations section were done in response to the Gen-ART reviewer, Sharon Chisholm. 8. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC4288] Freed, N. and J. Klensin, "Media Type Specifications and Registration Procedures", BCP 13, RFC 4288, December 2005. Taylor Standards Track [Page 4] RFC 4735 Example Media Types October 2006 Author's Address Tom Taylor Nortel 1852 Lorraine Ave Ottawa, Ontario K1H 6Z8 Canada EMail: taylor@nortel.com Taylor Standards Track [Page 5] RFC 4735 Example Media Types October 2006 Full Copyright Statement Copyright (C) The Internet Society (2006). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Intellectual Property The IETF takes no position regarding the validity or scope of any Intellectual Property Rights or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org. Acknowledgement Funding for the RFC Editor function is provided by the IETF Administrative Support Activity (IASA). Taylor Standards Track [Page 6]