A question on attribute Type of ds:Reference and its potential relationship with attribute MimeType of ds:Object

Dear all,

Some discussions within ESI group have made me to revisit both the 
attribute Type of ds:Reference and the attribute MimeType of the ds:Object.

Type of ds:Reference is defined as being of type URI, being its purpose 
(as we agreed) to identify the type of what will actually be digested. 
So far so good.

MimeType of ds:Object is of type string because it must contain the mime 
type identifier of what may be included in a ds:Object. I can also see 
its usefulness because there is a registry of MIME object types  and 
everybody knows it...

My question is why Type wihtin ds:Reference was selected to be an URI 
being its purpose to identify the type of what will actually be 
digested? I guess that because MIME does not cover every type of object 
that somebody could think to sign... but then who is in charge of 
defining these URIs identifying new types of data object types...?

Is this difference meaning that if I have to generate an enveloping 
signature of a type of document registered in MIME I should use the 
MimeType within ds:Object, whereas if it is not registered I should use 
the Type within ds:Reference and inventing some URI and agree with the 
recipient in the meaning of the URI?....in summary are these attributes 
different ways of indicating the same thing (of course when what is to 
be digested and the content of the ds:Object are the same thing) or 
there is some subtle thing here that I have missed?

Appologies if I am raising an already discussed issue.

Juan Carlos.

Received on Friday, 1 June 2007 12:29:02 UTC