The Case for Public Resource Identifiers A Call for Action

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The Case for Public Resource IdentifiersA Call
for Action
Steve Pepper, Ontopia Identity, Reference, and
the Web Workshop, Edinburgh, May 2006
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About this presentation

• Just a subset of my paper for this workshop
• 1. Introduction (on the need for identifiers)
• 2. Requirements on a Global Identifier Mechanism
• 3. Published Subjects
• 4. Alternative Proposals
• 5. Call to Action
• Focus here is on the Call for Action
• Expands on the ideas presented to the W3C AC
• http//www.w3.org/2006/05/pepper
• The Case for Published Subjects,http//www.ontopi
  a.net/topicmaps/materials/The_Case_for_Published_S
  ubjects.pdf

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URIs and the Towers of Babel

• URIs constitute a universal way of naming things
• This has tremendous potential
• Globally unique, language-independent identifiers
  for any conceivable subject under the sun
• We could finally stop building Towers of Babel
• (Or at least make a real impression on info glut)
• Whenever I say URI, please hear IRI

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The Semantic Superhighway

• At the very least, URIs give us the chance to
  create a semantic superhighway
• A foundation for solving the problem of infoglut
• A level of the Semantic Web below RDF
• But its not happening
• In fact, we are witnessing the creation of new
  Towers of Babel
• New, redundant vocabularies appear daily
• The potential is not being realised. Why?

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Why the Potential is Not Being Realised

• Too few people are using URIs as identifiers
• Its partly our fault
• We dont explain the benefits loudly enough
• We dont make it sufficiently easy and worthwhile
• Weve been in turmoil on technical issues
• And those that do use URIs as identifiers tend to
  create new ones, rather than reuse existing ones
• This defeats the purpose of a universal naming
  scheme

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Problems We Need to Address

• The concepts are too varied and confusing, and
  they are not being marketed well
• The world perceives a Heinz 59 variety of URIs
• IRI, URN, URL, httpURI, XRI, WPN, TDB, ...
• Reuse hard in practice
• No repositories to aid discovery
• No simple way to figure out what a given
  identifier is supposed to identify

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What We Need To Do

• Make the concepts easy to understand and apply
• Agree on one flavour of URI
• Promote the hell out of it
• Deprecate everything else
• Encourage reuse in every possible way
• Make it easy to discover and interpret
  identifiers
• Encourage them to be made public

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Make httpURIs the flavour of choice!

• Already widely used in Topic Maps and RDF
• And, increasingly, elsewhere
• No longer subject to paralysing controversy
• TAGs resolution of httpRange-14 issue allows any
  httpURI (including slash httpURIs) to identify
  anything
• Familiar to anyone who has used a web browser
• Having people type http//... will not be a
  problem
• Most importantly They resolve easily when you
  click on them
• So lets exploit that fact...

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Have them resolve to something useful!

• The most useful thing to resolve to would be a
  descriptor
• definition, description, some other kind of
  indication of what the identifier is intended to
  identify
• (machine-processable information would be a
  useful optional extra)
• Allows users to know what the identifier means
• i.e., what it is intended to identify
• ... and decide whether it is appropriate for them
  to use
• Also easy to discover using web search engines

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A Proposal for Public Resource Identifiers

• Three Key Principles
• A Public Resource Identifier (PRI pry) is
• an httpURI that has been minted for the explicit
  purpose of serving as an identifier
• It resolves to a Public Resource Descriptor (PRD)
• that describes which resource (subject) it
  identifies and states who minted it
• ANYONE should be able to mint a PRI
• A bottom-up mechanism (anarchic, like the Web)
• Survival of the fittest ( the most trusted)

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Sounds familiar?

• Essentially identical to Published Subjects
• Proposed by SC34 in 1999 as Public Subjects
• Refined within OASIS as Published Subjects
• Only major difference
• The requirement to use httpURIs
• But also a restatement of basic Web Architecture
  principles
• Cool URIs dont change
• httpURIs can identify anything
• httpURIs should resolve to something useful
• Does it matter what we call it?
• (Does it even need a new name?)
• A rose by any other name would smell as sweet

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Whats in a Name?

• Would this rose by any other name smell as sweet?
• Its a branding issue
• Does the name have useful / non-useful
  connotations?
• cf. resource and subject
• Can we create cool TLAs (if necessary)?
• pronouncable, depictable, available,
  distinguishable

The Paradigm Published Subjects Public Resource Identifiers
The URI published subject identifier public resource identifier
Abbrev. of the above PSI (?) PRI (pry)
Referent of the URI published subject indicator public resource descriptor
Abbrev. of the above PSI PRD
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A Call for Action Incubator Group

• Let the W3C and SC34 get together to push PRIs
• The details can be hammered out in a few months
• Then bring OASIS on board
• (before even more vocabularies appear...)
• Approach other standards bodies, including
• SC32 (databases, meta data), SC36 (e-learning),
  IFLA, and others (TBD)
• Lets build a Semantic Superhighway together
• I will be making a formal proposal shortly

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The PRI Incubator Group

• A W3C activity with participation from ISO and
  OASIS
• Chartered for lt 12 months to
• refine and codify the Three Key Principles
• provide absolutely minimal recommendations for
• the form of the PRI
• the content of the PRD
• address issues of branding and outreach
• esp. naming and strategy for promulgating the
  paradigm

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More on the PRI-XG

• Suggested participation
• 3 sponsors from W3C (TAG, SemWeb, ...)
• Invited international experts from ISO SC34
• Invited experts from OASIS (UBL, OpenOffice)
• Coordinator and team contact
• Suggested goals
• XG Report
• Possible fast-track as W3C Rec and ISO Technical
  Report

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The Continuation of a Fine Tradition

• Diderots Encyclopédie (17511780)
• THE DESCRIPTION OF EVERYTHING
• Oxford English Dictionary (18571928)
• THE MEANING OF EVERYTHING
• Public Resource Identifiers (1999 )
• THE IDENTITY OF EVERYTHING
• X