The use of MIME on the web: issues, toward a revised "finding" or joint W3C/IETF document

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The W3C TAG is discussing MIME registration and usage. 
See recent minutes at [1] and a related TAG action items [2].


The MIME documents in IETF RFCs are written generally, often with
usage of MIME in mind. I thought it would be useful to bring together
the various issues around MIME use on the Web. Although there are
some TAG findings on MIME type usage, there do seem to be a number
of open issues that recur, and are otherwise causing difficulty.

I was thinking of trying to document the issues, different points
of view, with an eye toward an update to TAG findings

I thought I would start discussion on, which seems 
like a good a place as any.

At the moment I'm collecting issues and pointers to possible
differing opinions, with the idea of a single document which
at least outlines the positions are, even if there isn't
agreement yet.

So I'm just gathering issues and pointers to documents,
arguments, bugs, mailing list archives at the moment.

Maybe doing this on a Wiki would be useful? In the meanwhile,
please feel free to email me privately.

I don't expect this work to hold anything up, but perhaps
have some future influence going forward.

Here's what I have so far as a set of issues:

* Authority of MIME labels vs. sniffing:

and internet draft
on MIME sniffing, as well as extended discussions on those.

* Inferring media type information when there is no label:

* "Polyglot" documents:
(i.e., a sequence of bits which, when labeled with different
types, has (reasonably) equivalent meanings).

* "Alternate" documents:
(i.e., a sequence of bits which has very different meanings
when labeled with different types, e.g., "as RDFa" vs "as HTML")

* Relationship between MIME types and embedded version identifiers:

* error handling and MIME types

* use of additional parameters
and difficulty of inferring

* The role of fragment identifiers in web content (which isn't 
used in email).

* Other media-description headers which aren't content-type
and their use (content-language)

* Updating MIME type registrations vs. new MIME type 


Received on Saturday, 3 April 2010 17:12:11 UTC