rfc2913.txt

<VC++网络游戏建摸与实现>源代码

6. Security Considerations

   This memo is not believed to introduce any security considerations
   that are not already inherent in the use of media feature tags and
   expressions [1,2].

7. Acknowledgements

   This proposal draws from discussions in the IETF 'conneg' working
   group.  The voice message example is based on some ideas by Glen
   Parsons.

   The author would like to thank the following people who offered
   comments that led to significant improvements:  Ted Hardie, Larry
   Masinter, Paul Hoffman, Jacob Palme, Ned Freed.












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8. References

   [1]  Klyne, G., "A Syntax for Describing Media Feature Sets", RFC
        2533, March 1999.

   [2]  Holtman, K., Mutz, A. and T. Hardie, "Media Feature Tag
        Registration Procedure", RFC 2506, March 1999.

   [3]  Crocker, D. and P. Overell, "Augmented BNF for Syntax
        Specifications: ABNF", RFC 2234, November 1997.

   [4]  Fielding, R., Gettys, J., Mogul, J., Frystyk, H. and T.
        Berners-Lee, "Hypertext Transfer Protocol -- HTTP/1.1", RFC
        2068, January 1997.

   [5]  Holtman, K. and A. Mutz, "Transparent Content Negotiation in
        HTTP", RFC 2295, March 1998.

   [6]  Wing, D., "Indicating Supported Media Features Using Extensions
        to DSN and MDN", RFC 2530, March 1999.

   [7]  Freed, N. and N. Borenstein, "Multipurpose Internet Mail
        Extensions (MIME) Part One: Format of Internet Message Bodies",
        RFC 2045, November 1996.

   [8]  Freed, N. and N. Borenstein, "Multipurpose Internet Mail
        Extensions (MIME) Part Two: Media Types", RFC 2046, November
        1996.

   [9]  Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA
        Considerations Section in RFCs", RFC 2434, October 1998.

  [10]  Hoffman, P., "Registration of Charset and Languages Media
        Features Tags", Work in Progress.

9. Author's Address

   Graham Klyne
   Content Technologies Ltd.
   1220 Parkview,
   Arlington Business Park
   Theale
   Reading, RG7 4SA
   United Kingdom

   Phone: [phone]
   Fax:   [phone]
   EMail: [e-mail]



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RFC 2913       MIME Content in Media Feature Expressions  September 2000


Appendix A: 'Type' feature tag registration

   -  Media Feature tag name(s):

         Type

   -  ASN.1 identifier associated with this feature tag:

         1.3.6.1.8.1.30

   -  Summary of the media features indicated:

         This feature tag indicates a MIME content type that a message
         agent is capable of handling, or that is contained within some
         message data.

         The content type consists of the MIME media type and subtype,
         presented using all lower case letters and with any whitespace
         characters removed.

   -  Values appropriate for use with this feature tag:

         String

   -  The feature tag is intended primarily for use in the following
      applications, protocols, services, or negotiation mechanisms:

         Any application that wishes to convey MIME content type
         information in a media feature expression.

   -  Examples of typical use:

         (type="image/tiff")

         (& (type="text/plain") (charset=US-ASCII) )

   -  Related standards or documents:

         MIME, RFC 2045 [7]

         MIME, RFC 2046 [8]

         Registration of Charset and Languages Media Features Tags [10]

   -  Considerations particular to use in individual applications,
      protocols, services, or negotiation mechanisms:

         (N/A)



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   -  Interoperability considerations:

         String feature matching is case sensitive, so consistent use of
         case for content type values and parameters is essential if
         content type value matching is to be achieved in a fashion
         consistent with MIME content type matching.

         Similarly, white space must be used consistently.

         This registration specifies a canonical form to be used for
         content type values (lower case letters and remove all
         whitespace).

   -  Related feature tags:

         (N/A)

   -  Intended usage:

         Common

   -  Author/Change controller:

         IETF



























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RFC 2913       MIME Content in Media Feature Expressions  September 2000


Full Copyright Statement

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Acknowledgement

   Funding for the RFC Editor function is currently provided by the
   Internet Society.



















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