Type vs MimeType (Re: ACTION-60)

On 2007-07-09 15:07:45 +0200, Juan Carlos Cruellas wrote:

> It could initially thought that ds:Reference's Type operates at a
> higher level than the ds:Object's mimeType, the first identifying
> that what is signed is a ds:Object and the second identifying
> that the media type of what is signed si for instance a pdf
> document. If this is true then these attributes could be seen as
> somehow orthogonal.

That sounds like a plausible interpretation to me.

> But this interpretation has one drawback:

> 1. If the signature is dettached and the signed data object is not a child 
> of a ds:Object, then how to report its media type?

The intent of the spec seems to be that an Object be used in these
cases; see the discussion toward the end of 2.2.  I don't see any
obvious way, though, to integrate a media type with a reference to
an external resource; that's probably an open point.

(In fact, from an architectural point of view, there's an
interesting tension between resources and their representations in
here as well...)

> If I am not wrong (and please forgive me if I am) the text in a
> MIME media type identifier could also be seen as a relative URI
> reference (a one having a relative-part= path-noscheme without
> query and fragment). If we may set the ds:Reference's Type
> attribute to a MIME media type then we may assert the media type
> of the dettached data object to be signed, but then we should 
> make it clear that both attributes overlap in their purposes.

That sounds a bit too much like shoe-horning an additional feature
into existing markup.  I'd suggest we note this in the wiki as an
issue for further work, and not make any changes in the PER.

Cheers,
-- 
Thomas Roessler, W3C  <tlr@w3.org>

Received on Monday, 9 July 2007 13:33:43 UTC