RE: [dss] Groups - dss-requirements-1.0-draft-02.doc uploaded

[Trevor Perrin <trevp@trevp.net>]

At 02:03 PM 3/26/2003 -0500, jmessing wrote:
>[...]
>Also, inasmuch as the transforms are explicitly listed, is it possible to 
>"backtrack" in order to retrieve the pre-transformed xml, should that be 
>desired, on the theory that "things equal to the same thing ...."?

No, there's no guarantee a transform will be reversible.  In fact, a 
transform could be any algorithm that takes some octets and returns some 
octets and is referenced by a URI, so there's not many guarantees at all 
(see http://www.w3.org/TR/xmldsig-core, 4.3.3.4).

As for the transforms that are already specified, canonicalization is not 
reversible, nor are the XPath Filtering and XSLT transforms likely to be.

Trevor