Agenda - XDI TC Call Wed. 7 December 9PM-10AM Pacific

XDI TC Members and Observers:

 

I apologize for the mix-up on last week's
call; I called in before others and when no one else was there, went to another
task. Take two tomorrow: we will discuss the same topic, this time with some
additional detail from the draft i-tag spec (copied at the end of this
message).

 

Following is the date/time, call-in info, and agenda for the next
unofficial

XDI TC telecon. 

 

Date:  Wednesday, 7 December 2005 USA

Time:  09:00AM - 10:00AM
Pacific Time

 

Dial-in number: 218-936-6666

Access Code: 2647893

 

AGENDA

 

1) DISCUSS XDI TRIPLE TRIPLE MODEL

This is a new proposal, inspired both by work on the "i-tag"
initiative (see

http://www.seedwiki.com/wiki/itag/itag.cfm and in particular

http://www.seedwiki.com/wiki/itag/power_i-tags.cfm?wpid=220488) as well
as

work on simple link contracts (as requested by Victor).

 

The proposal is that the XDI graph can be optimized not by just
limiting it

to 3 levels deep, but also 3 levels "across". This means that
everything in

the graph can be represented by an RDF "triple triple" -- a
maximum of 3

linked RDF triples - a Subject triple, a Predicate triple, and an
Object

triple.

 

We'll discuss as best we can in the absence of a shared whiteboard
(which we

may want to arrange for future meetings).

 

Following is an HTML excerpt from the
draft i-tag spec that explains this model in greater detail:

 

I-tag syntax is based on the RDF "subject-predicate-object"
statement model.XRIs are used to serializing these RDF statements because:

XRIs
support the use of global identifiers within other global identifiers (i.e.,
XRIs within XRIs, or URIs/IRIs within XRIs) in order to express structured, cross-context
relationships.

XRI
syntax enables the persistent identification of the resources (people,
organizations, dictionaries, media objects) participating in an i-tagging
relationship.

As applied to tagging, the RDF + XRI model maps as follows:

 

  
  
Statement
  part

  
  
  
Usage

  
 

 

  
  
Subject XRI

  
  
  
XRI identifing the authoritative
  source of the tag

  
 

 

  
  
Predicate XRI

  
  
  
XRI identifing the tag used
  to describe the media object

  
 

 

  
  
Object XRI

  
  
  
XRI that identifing the
  media object being tagged

  
 

 

This RDF model is then applied recursively one layer deep, so each of
the three XRIs above can also be expressed using its own RDF triple. This
yields the following matrix:

 

  
  
 

  
  
  
Subject

  
  
  
Predicate

  
  
  
Object

  
 

 

  
  
Subject
  XRI

  
  
  
XRI identifying the
  author asserting the i-tag
  (e.g. 

  i-name or URL)

  
  
  
XRI identifying the
  type of tag source (e.g., a blog, website, album)

  
  
  
XRI identifying the
  instance of the tag source (e.g. a blog name, web page name, album name)

  
 

 

  
  
Predicate
  XRI

  
  
  
XRI identifying the
  author defining the i-tag (e.g.
  

  i-name or URL)

  
  
  
XRI identifying the
  type of tag (e.g., tag, license, rating)

  
  
  
XRI identifying the
  instance of the tag type (e.g., tag name, license name, rating no.)

  
 

 

  
  
Object
  XRI

  
  
  
XRI identifying the
  author of the media object (e.g. 

  i-name or URL)

  
  
  
XRI identifying the
  type of media object (e.g. blog post, video, song)

  
  
  
XRI identifying the
  instance of the media object (e.g. blog post number, video name, song name)