Minutes: XRI TC Telecon Thursday 4/6

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

Following are the minutes of the unofficial XRI TC telecon held at:

Date:  Thursday, 6 April 2006 USA (Friday morning Asia)
Time:  4:00PM - 5:00PM PT

Event Description:
Weekly unofficial call that will continue until the end of the XRI 2.0
cycle.

PRESENT:

Drummond
Gabe
Les
(Regrets from Marty Schleiff)


AGENDA

1) PROPOSAL FOR ALPHANUMERIC VERSION IDENTIFIER SYNTAX
See http://lists.oasis-open.org/archives/xri/200604/msg00005.html.

The following points were made in discussion of this proposal:

* It has the advantage of providing one default version identifier format
that accommodates both numeric and alpha version identifiers.

* The normalization and comparison rules, though longer than those for the
purely numeric version identifiers in XRI Metadata 2.0 CD01, are still
straightforward and produce unambiguous results.

* One downside of this more expressive format is the classic tradeoff that
greater expressiveness means greater requirements for normalization prior to
comparison. This means an application that wants to compare two XRIs for
equivalence with the lowest possible chance of a false negative will need to
normalize the version identifiers in any $v cross-references. For example,
the version values in the following two XRIs would both need to be
normalized before they could be determined to be equivalent.

	NON-NORMALIZED
	#1	xri://(example.root)/resource*($v*02a1)
	#2	xri://(example.root)/resource*($v*2-a1)

	NORMALIZED
	#1	xri://(example.root)/resource*($v*2.a.1)
	#2	xri://(example.root)/resource*($v*2.a.1)

2) PROPOSAL FOR DATE-ONLY AND TIME-ONLY SUBTAGS FOR DATETIME
No formal proposal has been submitted yet but we discussed the proposed
approach, which is to keep the same default for datetime identifier values
as in XRI Metadata 2.0 CD01, but add two subtags ("date" and "time") that
can be used to express just a date or just a time. Following are examples of
XRIs showing the full range of options that would be supported.

	xri://(example.root)/resource*($d*2000-01-12T12:13:14Z)
	xri://(example.root)/resource*($d*date*2000-01-12)
	xri://(example.root)/resource*($d*date*2000-01)
	xri://(example.root)/resource*($d*date*2000)
	xri://(example.root)/resource*($d*time*12:13:14Z)
	xri://(example.root)/resource*($d*time*12:13)
	xri://(example.root)/resource*($d*time*12)

=Drummond