RFC 4281 on The Codecs Parameter for "Bucket" Media Types

A new Request for Comments is now available in online RFC libraries.

        RFC 4281

        Title:      The Codecs Parameter for "Bucket" Media Types
        Author(s):  R. Gellens, D. Singer, P. Frojdh
        Status:     Standards Track
        Date:       November 2005
        Mailbox:    randy@qualcomm.com, singer@apple.com,
                    Per.Frojdh@ericsson.com
        Pages:      12
        Characters: 25529
        Updates/Obsoletes/SeeAlso:    None

        I-D Tag:    draft-gellens-mime-bucket-04.txt

        URL:        ftp://ftp.rfc-editor.org/in-notes/rfc4281.txt

Several MIME type/subtype combinations exist that can contain
different media formats.  A receiving agent thus needs to examine
the details of such media content to determine if the specific
elements can be rendered given an available set of codecs.
Especially when the end system has limited resources, or the
connection to the end system has limited bandwidth, it would be
helpful to know from the Content-Type alone if the content can be
rendered.

This document adds a new parameter, "codecs", to various
type/subtype combinations to allow for unambiguous specification of
the codecs indicated by the media formats contained within.

By labeling content with the specific codecs indicated to render the
contained media, receiving systems can determine if the codecs are
supported by the end system, and if not, can take appropriate action
(such as rejecting the content, sending notification of the
situation, transcoding the content to a supported type, fetching and
installing the required codecs, further inspection to determine if
it will be sufficient to support a subset of the indicated codecs,

This is now a Proposed Standard Protocol.

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.

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Joyce K. Reynolds and Sandy Ginoza
USC/Information Sciences Institute

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