Subject: RE: [uddi-spec] ASN.1 notation as an alternative to XML Schema proposal
I concur with Claus’ well-put thoughts.
The task of dealing with the signatures that Claus mentions is not a small one. The heavy lifting of the design work of V3 in this respect was coming up with an appropriate canonicalization algorithm for XML-schema-specified XML (in the ASN.1 world this is in analogy to the specification of the Distinguished (binary) Encoding Rules as opposed to the Basic Encoding Rules). This algorithm is hand-in-glove intimate with the expressivity of XML-schema (as were the DER with respect to the expressivity of BER). Unless XML Schema and XML-encoded-ASN.1 were entirely isomorphic (which would astound me, but I admit I do not know for certain that they are not), then defining ASN.1 equivalents of the UDDI v3 XML schemas than when XML Encoded and canonicalized by ASN.1-derivied algorithms manages to preserve the signature will be a Herculean task.
Shishir: Not that I’ve looked (sorry), but it is even the case that all UDDI v2 XML instances which are valid according to the UDDI v2 XML Schema definitions are in fact valid according to the XML Encoding Rules (Basic or otherwise) of the sample ASN.1 schemas for UDDI v2 that you provided? That is can we take reliably data produced according to the XML Schema mechanism and validate it according the ASN.1-derived mechanism? Can we reliably do it the other way around?
From: Von Riegen,
Thanks for the details on ASN.1.
However, adding a notation alternative to XML Schema and a protocol alternative to SOAP/HTTP to the set of UDDI Version 2 specifications at this point in time seems not to be appropriate to me. There are other schema notations, such as RELAX NG, and other protocols, such as HTTP w/o SOAP, we could also consider, but we always limited our scope to the most common ones so far.
I'm not saying that it is not useful to propose alternatives, but since alternative schema notations and protocols should note change UDDI's core, I'd rather like to see them added layered on top of the UDDI specifications, for example, by starting with a technical note.
Also, since we are also in the process to finalize UDDI Version 3, any alternatives should also work with this version. The issue with the mapping of W3C XML Digital Signatures to ASN.1 that came up yesterday should be one of the first items to be resolved in a Technical Note.
As discussed briefly on today's call, here are the initial documents to get the discussion going. The doc file contains a description of what is in this proposal, along with a few examples to make the case clear.
We are not necessarily aiming to make it to the V2 specification (since it was just sent to the OASIS board for review), but we are not sure if it should just become a Technical Note and be left at that.
Lets look for all the feedback we can get on this proposal.
Attached: Overview doc + UDDI V2 converted schemas