Minutes:Joint XRI & XDI TC Telecon Thursday 2007-06-21

["Drummond Reed" <drummond.reed@cordance.net>]

Following are the minutes of the joint unofficial telecon of the XRI and XDI

TCs at:

 

Date:  Thursday, 5 July 2007 USA

Time:  11:30AM - 12:30PM Pacific Time

 

Event Description:

Weekly unofficial joint call of the XRI and XDI Technical Committees.

 

ATTENDING

 

Les Chasen

Drummond Reed

Markus Sabadello

Gabe Wachob (second half)

 

 

AGENDA

 

1) DISCUSSION OF THE GLOBALID SYNONYM PROPOSAL

 

The XRI Resolution editors have continued analysis and discussion of this proposal as detailed on the XRI TC wiki at:

 

      http://wiki.oasis-open.org/xri/XriCd02/CanonicalIdVerification

 

We discussed the following table from the proposed text for XRI Resolution 2.0 Working Draft 11 Editor’s Draft 03.

 

 

******** EXCERPT FROM ED03 SYNONYM SECTION ********

 

XRI resolution includes support for synonyms—XRIs, IRIs, or URIs that are not character-for-character equivalent, but which identify the same target resource (in the same context, or across different contexts).  Table 23 describes the five types of synonyms may be expressed in XRDs.

Synonym Element	Cardinality	Identifier Scope	Authority Scope	Follow for additional XRDS?
LocalID	Zero-or-more	Relative	Hierarchical	No
GlobalID	Zero-or-more	Absolute	Hierarchical	No
CanonicalID	Zero-or-one	Absolute	Hierarchical or polyarchical	No
Ref	Zero-or-more	Absolute	Polyarchical	Yes
Backref	Zero-or-more	Absolute	Polyarchical	No

Table 23: The five XRD synonym elements.

 

********* END EXCERPT **********

 

The discussion focused on the following points:

 

* Making CanonicalID cardinality zero-or-one reduces confusion about multiple CanonicalIDs, but also means that if the CanonicalID an XRI authority wants to assert for a target resource changes, the identifier that was previously asserted as a CanonicalID will no longer appear as a CanonicalID. Drummond calls this “CanonicalID migration”. It will generally only happen when a target resource first identified in a local context later becomes identified in a global context. When that happens, one or more XRI authorities producing XRDs describing the target resource may want to change the CanonicalID from a value they originally assigned locally (i.e., a value that is also a valid GlobalID) to a polyarchical CanonicalID. However in this case, the value that was previously asserted as a CanonicalID for the target resource could now be asserted as a GlobalID, so it still serves to absolutely identify the target resource.

 

* Wil and Markus have both pointed out in email that value of a GlobalID can be deduced from the value of a LocalID element in all previous XRDs in the chain of resolution. However Drummond pointed out that a GlobalID still adds information in that it selects a specific subset of those LocalIDs to produce an absolute GlobalID. In most cases this will be a subset of the LocalIDs in the resolution chain that are persistent identifiers, vs. other LocalID values that may be reassignable.

 

# DRUMMOND to update http://wiki.oasis-open.org/xri/XriCd02/CanonicalIdVerification with these points.

 

# DRUMMOND to go over the updated proposal with Gabe (who had to drop off the call).

 

# DRUMMOND to complete a writeup of this proposal in context so the editors can review it in the context of ED03.

 

2) SCHEDULE FOR XRI RESOLUTION 2.0 WORKING DRAFT 11 ED03

 

Drummond reported that he will have dedicated editing time on ED03 next week, so his goal is to have ED03 posted in time for next week’s telecon.