Minutes: XDI TC Telecon Thursday 2011-06-30

Following are the minutes of the unofficial telecon of the XDI TC at:

Date:  Thursday, 30 June 2011 USA

Time:  1:00PM - 2:00PM Pacific Time (20:00-21:30 UTC)

ATTENDING

Giovanni Bartolomeo 

Joseph Boyle 

Mike Schwartz 

Drummond Reed

Bill Barnhill

GUESTS

Henrik Sandell

THE IDEARPAD LINK FOR TODAY IS:

     http://xdi.idearpad.org/34

1) UPDATE ON OPENXDI PROGRESS

Mike
 gave an update that OpenXDI is planning to put out the 0.0 release this
 week. The only item that will be missing that was planned for this 
release will be link contracts. The plan will be to include 
authentication and authorization with link contracts in 0.1 next week.

2) PREPARATIONS FOR XDI 1.0 SPEC RELEASE

We
 discussed two items that will be important to deliver along with the 
XDI 1.0 specs. The first is the XRI 3.0 specifications. Drummond 
explained that the XRI TC's stance has been that the XRI 3.0 Working 
Draft is stable and is ready to move forward, they are only waiting for 
the XDI 1.0 specs to be ready, as many of the best XRI examples will be 
from XDI 1.0.

The second is a comparison between XDI and RDF. Giovanni pointed out that there are still at least two open issues:

The use of $is for both equivalence and inverse statements -- will this be compatible with RDF?

The current proposal for $is synonym statements between separate nodes - is this approach fully compatible with RDF?

Giovanni feels that it is important for these issues to be considered prior to finalizing our 1.0 specs.

We
 discussed the advantages of having a clearly mapped relationship 
between XDI and RDF. Mike asked how important compability is if XDI is 
solving the problems we are currently addressing (such as portable 
authorization with link contracts). Giovanni pointed out the size of the
 RDF Linked Data project (with over 20 billion RDF triples). 

Bill
 brought the perspective that there are many use cases for how XDI can 
and may be used beyond the personal data sharing use cases in which some
 TC members have a strong interest. For example Bill feels there is a 
significant market in using XDI for data analysis where OWL is not well 
suited.

Giovanni
 wants to make sure the XDI TC doesn't reproduce the problem that the 
XRI TC had, which was to push a specification to an OASIS Standard vote 
that did not have buy-in from the W3C, and thus resulted in being the 
first OASIS Standard in history to fail at an OASIS Standard vote. 
Giovanni noted that this lesson proved valuable in the end, and Drummond
 strongly agreed - the XRI 3.0 spec is much the better for it.

Drummond
 suggested that to finally solve these longstanding questions about RDF 
compatability will take a renewed deep-dive focus on these issues and 
proposals for innovative solutions that provide RDF compability without 
constraining the unique capabilities of the XDI graph model.

3) JIRA ISSUE TRACKING

Bill pointed out that we haven't been using Jira to track issues yet even though we are now set up for it.

#
 BILL will contact Robin Cover to set up a tutorial telecon so we can 
get everyone in the TC up to speed on using Jira to do issues 
management.

# DRUMMOND will put Jira issues review at the start of each telecon agenda.

4) MOVING FROM METAGRAPH SYMBOLS TO METAGRAPH WORDS

See Drummond's email to the list and subsequent discussion:

  http://lists.oasis-open.org/archives/xdi/201106/msg00029.html

Drummond
 summarized last week's discussion, and said that is really becomes an 
aesthetic decision by the TC, since $ ==>$is, * ==> $has, and ! 
==> $a are functionality identical.

Bill
 said that he is in favor of moving back to metagraph words for these 
symbols, but feels we should have separate $words for equivalence and 
inversion. 

Giovanni
 pointed out that even though RDF does not have an algorithmic way to 
express inversion, Linked Data does suggest that nodes that are linked 
also include the inverse link so that you can discover the relationship 
in both directions.

Note that by itself, adopting a separate $word for inversion is not a solution to the RDF incompability issue.

# ALL - Send your stack-ranked choice for a new $word for asserting inversion as an email to the list before next week's call.

5) LINK CONTRACT PROCESSING ANALYSIS AND RECOMMENDATION

Drummond sent an email to the list about this topic:

  http://lists.oasis-open.org/archives/xdi/201106/msg00041.html

He
 explained that it is a high-priority discussion to support the 
implementation of link  contracts at the OpenXDI Project. See also the 
last link contract  example patterns in:

  http://www.oasis-open.org/committees/download.php/42654/xdi-graph-patterns-2011-06-23.pdf

  http://www.oasis-open.org/committees/download.php/42656/xdi-statements-for-xdi-graph-patterns-2011-06-23.pdf

Drummond
 ran through the login in the email that it can save enormous processing
 load on XDI servers everywhere if the XDI protocol if:

Every request is limited to data covered by a single link contract

The request MUST include a reference to the governing link contract.

There
 was consensus that these requirements made sense. Thus the next step is
 to arrive at consensus on the format of this reference in an XDI 
message.

# BILL will add an issue in Jira to cover this as an open issue.

6) NEXT CALL

The next call is next week at the regular time. 

------------

ONGOING ISSUES LIST

Each of these is a candidate for the agenda for future calls.

* DO WE NEED SEPARATE METAGRAPH WORDS FOR EQUIVALENCE AND INVERSION? (added 2011-06-30 - Giovanni)

This is an open issue because does not have a direct corallary in RDF.

* SYNONYM HANDLING (added 2011-06-30 - Giovanni)

This remains an open issue because it raises challenges with compatibility with RDF.

* TRANSACTIONAL INTEGRITY FOR XDI (added 2011-03-24)

Since 
 versioning, as one example, involves multiple transactions that must 
be  commited as a group, we will need to address transactional 
integrity.  Specifically, we need to define how this will be handled at 
the protocol  level, vs. the implementation level.

* PROPOSED CONSTRUCTS/OPERATORS FOR XDI

Discuss the following wiki page originally posted by Giovanni:

  http://wiki.oasis-open.org/xdi/XdiNewFoundation

* DICTIONARY STRUCTURE

Mike would like an example of the PDX dictionary as soon as we can do it.

*   EQUIVALENCE SEMANTICS

Close on whether we need an additional $ word that is the equivalent

of Higgins Personal Data Model (PDM)  semantics   of h:correlation,

which is not as strong as $is.

      http://lists.oasis-open.org/archives/xdi/201006/msg00036.html

* COOL URIS

Continue previous discussion about the use of standard RDF URIs in XDI:

  http://lists.oasis-open.org/archives/xdi/201006/msg00023.html