Semantic Web: Building on what exists

Building on what exists

http://www.w3.org/2006/Talks/0404-mit-tbl

Tim Berners-Lee

MIT Computer Science & Artificial Intelligence Laboratory (CSAIL)
Decentralized Information Group

Director, World Wide Web Consortium (W3C)

This talk


Semantic Web motivation

SW: Everything has a URI

Don't say "colour" say <http://example.com/2002/std6#col>

The relational database

A database's row, column and cell are subject, property and value.

The element of the Semantic Web

arrow tail, body and head are l are subject, property and value.

Semantic web includes tables,...

Arrows can make a table, an arrow from each row to each value

...trees

Arrows can make a table, an arrow from each row to each value

... everything

Arrows can make a table, an arrow from each row to each value

RDF data...

a set of circles and arrows

...merges just like that.

more circles and arrows superim

Subject and object node using same URIs

RDF: Semantic links - "Joining the Web"

 Links between column headings

Verb/predicate/Property using same URIs

What will it be like?

AGFA: Semantic web bus

The semantic web bus connects medical decision making systems

Thanks to Helen Chen, AGFA

AGFA: Semantic web workflow

The semantic web bus connects medical decision making systems

Thanks to Helen Chen, AGFA

Why does it take time?

Roadmap: Stack of expressive power

architectural layers

The Semantic Web Wave

The wave is coming...get out your surfboard

Current Semantic Web work

(*New!)

Practical Semantic Web

Practical Semantic Web

Bottom-up ontology design

  1. Start with existing SQL databases
  2. Add information about how keys and foreign keys connect
  3. Remove other artefacts of the DB schema
  4. Note relationships to other people's concepts

RDF views of data

RDF is to data what HTML is to documents

SPARQL access to data

Query interface

SPARQL - the universal query service

Clients of the RDF bus

New data applications can be built on top of RDF bus, for example:

db to sw

Components: Adapting random files

Keep your existing systems running - adapt them

db to sw

Components: Triple store

Virtual severs actually figure stuff out as well as look up data

db to sw

Adapting SQL Databases

Keep your existing systems running - adapt them

db to sw

Adapting XML

Remember- RDF on an HTTP server can always be virtual

db to sw

Adapting XML: GRDDL

Remember- RDF on an HTTP server can always be virtual

db to sw

Components: Smart servers

Virtual severs actually figure stuff out as well as look up data

db to sw


Communities and Vocabularies

Universal WWW must include communities on many scales

Applications connected by concepts

Its like a metro, the way the lines of common concepts connect the stations of different applications

For example in biopax

Venn diagram showing ontologies overlapping by certain common terms

[Diagram: Joanne Luciano, Predictive Medicine; Drug discovery demo using RDF, Sideran Seamark and Oracle 10g]

Fractal Web of concepts

The semantic web is about allowing data systems to change by evolution not revolution

Total Cost of Ontologies (TCO)

Assume :-) ontologies evenly spread across orders of magnitude; committee  size as log(community), time as committee^2, cost shared across community.
Scale Eg Committee size Cost per ontology (weeks) My share of cost
0 Me 1 1 1
10 My team 4 16 1.6
100 Group 7 49 0.49
1000 10 100 0.10
10k Enterprise 13 169 0.017
100k Business area 16 256 0.0026
1M 19 361 0.00036
10M 22 484 0.000048
100M National, State 25 625 0.000006
1G EU, US 28 784 0.000001
10G Planet 31 961 0.000000

Total cost of 10 ontologies: 3.2 weeks. Serious project: 30 ontologies, TCO = 10 weeks.
Lesson: Do your bit. Others will do theirs.
Thank those who do working groups!

Adopting standards

Costs Benefit (standard fails) Benefit (standard succedes)
Plan A
  • Standards group participation
  • Product transition
  • Standard promotion (?)
  • conformance to a sidelined standard
  • Market size jump
  • Market share jump
Plan B
  • Normal product development
  • Normal product promotion
  • Business as usual
  • Market share loss
  • Catch-up cost

Often, Participation carries the least risk
(more...)

Timing strawman

Good news

Future: Policy aware, Transparent web of data

Thank You

More:

w3.org

Thank you for your attention

http://www.w3.org/2006/Talks/0404-mit-tbl