- From: Erich Bremer <erich@ebremer.com>
- Date: Thu, 24 Jan 2013 10:35:58 -0500
- To: WebID Group <public-webid@w3.org>
Hi, I am relatively new to the WebID party so I apologized if this has been discussed already. I didn't see any mentions of it in the group's e-mail archives. When I was considering my response to the WebID hash questionnaire last night, to me, many of the arguments in the definition of WebID of whether to hash or not to hash stem from conflation of URI and URL in the X509v3 Subject Alternative Name. Has the use of X509v3 Custom Extensions been considered to help support the location of the data about the URI as specified in Subject Alternative Name rather than infer it from the Subject Alternative Name itself? Custom extensions are permissible in X509v3: Extensions ::= SEQUENCE SIZE (1..MAX) OF Extension Extension ::= SEQUENCE { extnID OBJECT IDENTIFIER, critical BOOLEAN DEFAULT FALSE, extnValue OCTET STRING } references: http://www.openssl.org/docs/apps/x509v3_config.html#ARBITRARY_EXTENSIONS http://www.ietf.org/rfc/rfc3280.txt Several custom extensions/OIDs could be created to tell the validating server *where* to find the data. Roughly, create the following scenarios: 1) No custom extensions listed - default behavior, use the URI in Subject Alternative Name as a URL for the profile (removing the hash if necessary) 2) OID A.B.C.1 - explicitly specify a URL for the profile rather than infer it. 3) OID A.B.C.2 - specify a SPARQL Endpoint URL - I don't see why a WebID could not be validated against a SPARQL endpoint and it would allow the validating server to pick ala cart what it wants rather than download the whole file. 4) OID A.B.C.3 - specify a LDP 5) OID A.B.C.4 - specify URL for the SPARQL 1.1 Graph Store HTTP Protocol Providing these data location hints to the validating server in the form of custom X509v3 extensions would appear to be useful and Subject Alternative Name could then just be a URI rather than a URI/URL. - Erich http://www.ebremer.com
Received on Thursday, 24 January 2013 15:37:23 UTC