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Draft message to TAG on TAG issue uriMediaType-9

From: David Orchard <dorchard@bea.com>
Date: Wed, 3 Dec 2003 16:12:36 -0800
To: <xml-dist-app@w3.org>
Message-ID: <012001c3b9fb$53507ee0$d902200a@beasys.com>

Hi,

Draft message follows:

Dear TAG,

On behalf of the XML Protocol working group, we would like to request a
revision of uriMediaType-9 [1] and the related finding [2], and that this be
prioritized sufficiently to enable a speedy resolution, preferably by early
January.  This issue is currently open and listed as being closed after v1.0
Web Architecture document.  We observe that there have been  recent updates
by Iana, particularly the provision of http uris for media types [3] and urn
URIs for IANA parameters such as media types in RFC 3553 [4].

By way of background, the XML Protocol Working group and the Web Services
Description Working Group have formed a task force to specify the
representation and descripion of binary content in SOAP.  There is a
requirement to be able to identify in the representation the media type of
the binary content.

We seem to have 3 major options available for identifying media types in
XML:
1) IANA media type strings, ie xsi:mediaType="image/jpeg".
2) HTTP URIs, ie
xsi:mediaType="http://www.iana.org/assignments/media-types/image/jpeg"
3) URN URIs, ie xsi:mediaType="urn:ietf:param:contentType:image:jpeg"

We note that example #2: is not guaranteed to be dereferencable (the example
given is not dereferencable at the time of this writing); it is a
manufactured URI and we're not sure that it is valid; we're not sure about
the longevity of those URIs;  and we sense that option #2 is less preferred
by IETF than option #3.  We also note that option #1 appears to more
naturally fit with existing software that deals with media types.  A finding
that describes the benefits and costs of the approaches and helped us in our
decision would be appreciated.

We are not asking the question about the namespace name nor the local name
of the attribute, simply the content model of the attribute.  The use of
xsi: as the prefix is only to illustrate one possible namespace name that
could be created within the W3C.

Cheers,
Dave

[1] http://www.w3.org/2001/tag/issues.html#uriMediaType-9
[2] http://www.w3.org/2001/tag/2002/01-uriMediaType-9
[3] http://www.iana.org/assignments/
[4] http://www.ietf.org/rfc/rfc3553.txt
Received on Wednesday, 3 December 2003 19:13:02 GMT

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