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Network Working Group                                        R. CastagnoRequest for Comments: 3839                           Nokia Mobile PhonesCategory: Standards Track                                      D. Singer                                                    Apple Computer, Inc.                                                               July 2004MIME Type Registrations for3rd Generation Partnership Project (3GPP) Multimedia filesStatus 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 (2004).Abstract   This document serves to register and document the standard MIME types   associated with the 3GPP multimedia file format, which is part of the   family based on the ISO Media File Format.1.  Introduction   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 inBCP 14,RFC 2119   [RFC2119].   The third-generation partnership project (3GPP) for third-generation   cellular telephony has defined a standard file format to contain   audio/visual sequences which may be downloaded to cellular phones   [3GPP].  At the time of writing, the 3GPP file format (3GP) can   contain H.263 or MPEG-4 video, and AMR Narrow-band speech, AMR wide-   band speech, or AAC audio, and 3GPP timed text.   Within the file, as with all files in the 'ISO' family, there is an   intrinsic file-type box, which identifies those specifications to   which the file complies, and which players (possibly compliant with   only one specification) are permitted by the content author to play   the file.  This identification is through four-letter 'brands'.Castagno & Singer           Standards Track                     [Page 1]

RFC 3839            MIME Type Registrations for 3GPP           July 2004   Files identified by the MIME [MIME1] type defined here MUST contain a   brand defined in a standard issued by 3GPP that can apply to 3GPP   files, in their compatible brands list.   The MIME types defined here are needed to correctly identify such   files when they are served over HTTP, included in multi-part   documents, or used in other places where MIME types are used.2.  Security Considerations   The 3GPP file format may contain audio, video, and displayable text   data.  There is currently no provision for 'active' elements (such as   scripts) of any kind.   Clearly it is possible to author malicious files which attempt to   call for an excessively large picture size, high sampling-rate audio   etc.  However, clients can and usually do protect themselves against   this kind of attack.   It should be noted that selected metadata fields may encompass   information partly intended to protect the media against unauthorized   use or distribution.  In this case, the intention is that alteration   or removal of the data in the field would be treated as an offense   under national agreements based on World Intellectual Property   Organization (WIPO) treaties.   3GPP files have an extensible structure, so that it is theoretically   possible that metadata fields or media formats could be defined in   the future which could be used to induce particular actions on the   part of the recipient, thus presenting additional security risks.   However, this type of capability is currently not supported in the   referenced specification.   There is no current provision in the standards for encryption,   signing, or authentication of these file formats.3.  MIME Types   This registration applies to all files defined as using the '3GP'   file format and identified with a suitable brand in a 3GPP   specification.  The usual file suffix for all these files is ".3gp".3.1.  Files with audio but no video   The type "audio/3gpp" may be used for files containing audio but no   visual presentation (neither video nor timed text, for example).Castagno & Singer           Standards Track                     [Page 2]

RFC 3839            MIME Type Registrations for 3GPP           July 2004   To: ietf-types@iana.org   Subject: Registration of Standard MIME media type audio/3gppMIME media type name:              audioMIME subtype name:                 3gppRequired parameters:               noneOptional parameters:               none                                    Ongoing work related to this                                    registration may introduce new                                    optional parameters.  One example                                    area of effort may introduce a                                    parameter that would allow for                                    codecs in use within the MIME type                                    to be asserted and determined                                    without examination of the file.                                    Those with interests in the area                                    should monitor registrations for                                    updates.Encoding considerations:           files are binary and should be                                    transmitted in a suitable encoding                                    without CR/LF conversion, 7-bit                                    stripping etc.; base64 is a suitable                                    encoding.  Note that this MIME type                                    is used only for files; separate                                    types are used for real-time                                    transfer, such as for the RTP                                    payload format for AMR audio                                    [RFC3267].Security considerations:           see the security considerations                                    section inRFC 3839Interoperability considerations:   The 3GPP organization has defined the                                    specification, interoperability, and                                    conformance, and conducts regular                                    interoperability testing.Published specification:           3GPP 26.234, Release 5; 3GPP 26.244,                                    Release 6 or later.  3GPP                                    specifications are publicly                                    accessible at the 3GPP web site,                                    www.3gpp.org.Applications which use this media type: Multi-mediaAdditional information:            The type "audio/3gpp" MAY be used for                                    files containing audio but no visual                                    presentation.  Files served under                                    this type MUST NOT contain any                                    visual material. (Note that 3GPP                                    timed text is visually presented                                    and is considered to be visual                                    material).Castagno & Singer           Standards Track                     [Page 3]

RFC 3839            MIME Type Registrations for 3GPP           July 2004Magic number(s):                   None.  However, the file-type box                                    must occur first in the file, and                                    MUST contain a 3GPP brand in its                                    compatible brands list.File extension(s):                 3gp and 3gpp are both declared athttp://www.nist.gov/nics/; 3gp is                                    preferredMacintosh File Type Code(s):       '3gpp'Person & email address to contact for further information:                                    Nokia MIME manager, mime@nokia.comIntended usage:                    COMMONChange controller:                 3GPP3.2.  Any files   The type "video/3gpp" is valid for all files.  It is valid to serve   an audio-only file as "video/3gpp".   To: ietf-types@iana.org   Subject: Registration of Standard MIME media type video/3gppMIME media type name:              videoMIME subtype name:                 3gppRequired parameters:               noneOptional parameters:               noneEncoding considerations:           files are binary and should be                                    transmitted in a suitable encoding                                    without CR/LF conversion, 7-bit                                    stripping etc.; base64 is a suitable                                    encoding.  Note that this MIME type                                    is used only for files; separate                                    types are used for real-time                                    transfer, such as for the RTP                                    payload formats for H.263                                    [RFC2429] and AMR audio                                    [RFC3267].Security considerations:           see the security considerations                                    section inRFC 3839Interoperability considerations:   The 3GPP organization has defined the                                    specification, interoperability, and                                    conformance, and conducts regular                                    interoperability testing.Published specification:           3GPP 26.234, Release 5; 3GPP 26.244,                                    Release 6 or later.  3GPP                                    specifications are publicly                                    accessible at the 3GPP web site,                                    www.3gpp.org.Applications which use this media type: Multi-mediaCastagno & Singer           Standards Track                     [Page 4]

RFC 3839            MIME Type Registrations for 3GPP           July 2004Additional information:Magic number(s):                   None.  However, the file-type box                                    must occur first in the file, and                                    MUST contain a 3GPP brand in its                                    compatible brands list.File extension(s):                 3gp and 3gpp are both declared athttp://www.nist.gov/nics/; 3gp is                                    preferredMacintosh File Type Code(s):       '3gpp'Person & email address to contact for further information:                                    Nokia MIME manager, mime@nokia.comIntended usage:                    COMMONChange controller:                 3GPP4.  IANA Considerations   This document registers the MIME types audio/3gpp and video/3gpp,   defined above.5.  Acknowledgments   The review of the 3GPP SA4 committee is gratefully acknowledged, in   particular Per Frojdh.  The chairs of the AVT working group, in   particular Colin Perkins, have provided both excellent guidance and   feedback, for which the authors are grateful.6.  References6.1.  Normative References   [3GPP]    Published specifications in releases 5 and 6:  Release 5:             3GPP TS 26.234: Transparent end-to-end packet switched             streaming service (PSS); Protocols and codecs.  Release 6:             3GPP TS 26.244: Transparent end-to-end packet switched             streaming service (PSS); 3GPP file format (3GP)   [MIME1]   Freed, N. and N. Borenstein, "Multipurpose Internet Mail             Extensions (MIME) Part One: Format of Internet Message             Bodies",RFC 2045, November 1996.   [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate             Requirement Levels",BCP 14,RFC 2119, March 1997.Castagno & Singer           Standards Track                     [Page 5]

RFC 3839            MIME Type Registrations for 3GPP           July 20046.2.  Informative References   [RFC2429] Bormann, C., Cline, L., Deisher, G., Gardos, T., Maciocco,             C., Newell, D., Ott, J., Sullivan, G., Wenger, S. and C.             Zhu, "RTP Payload Format for the 1998 Version of ITU-T Rec.             H.263 Video (H.263+)",RFC 2429, October 1998.   [RFC3267] Sjoberg, J., Westerlund, M., Lakaniemi, A. and Q. Xie,             "Real-Time Transport Protocol (RTP) Payload Format and File             Storage Format for the Adaptive Multi-Rate (AMR) and             Adaptive Multi-Rate WideBand (AMR-WB) Audio Codecs",RFC3267, June 2002.7.  Authors' Contact Information   Roberto Castagno   Nokia Mobile Phones   PO Box 88, FIN-33721 Tampere   (Tieteenkatu 1, FIN-33720 Tampere)   Finland   Phone: +358 7180 35796   EMail: roberto.castagno@nokia.com   David Singer   Apple Computer, Inc.   One Infinite Loop, MS:302-3MT   Cupertino  CA 95014   USA   Phone: +1 408 974 3162   EMail: singer@apple.comCastagno & Singer           Standards Track                     [Page 6]

RFC 3839            MIME Type Registrations for 3GPP           July 20048.  Full Copyright Statement   Copyright (C) The Internet Society (2004).  This document is subject   to the rights, licenses and restrictions contained inBCP 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 inBCP 78 andBCP 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 athttp://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 currently provided by the   Internet Society.Castagno & Singer           Standards Track                     [Page 7]