flink: lessons of interoperability
DESCRIPTION
Flink: Lessons of interoperability. Peter Mika Dept. of Business Informatics Free University Amsterdam http://www.cs.vu.nl/~pmika/ 1 st Intl. Workshop on Interoperability of SW portals. Content. Flink Interoperability Flink + Interoperability. What is Flink?. - PowerPoint PPT PresentationTRANSCRIPT
Flink: Lessons of
interoperability
Peter Mika Dept. of Business Informatics
Free University Amsterdam http://www.cs.vu.nl/~pmika/
1st Intl. Workshop on Interoperability of SW portals
Content
Flink Interoperability Flink + Interoperability
What is Flink?
Flink is a directory of Semantic Web research Browse the social network of all authors at ISWC ‘01-’04 Profiles with personal information, emails, publications View statistics Download profiles in FOAF format Export for Social Network Analysis
Demonstration of latest SW technology 1st prize at the Semantic Web Challenge (2004) Open source (soon) Try it!
http://flink.semanticweb.org
Technology highlights
Social network mining from the Web and other legacy sources (emails, publications)
Social networks based ontology extraction Collection of FOAF data from the SW (“scuttering”) Aggregation and identity reasoning (“smushing”)
Custom inferencing using Sesame OWL use
sameAs, inverse functional properties Web Service integration
geographic lookup WML interface …
JUNGNetwork API
Semantic Web Web
Sesame
FOAF profiles
Web mining
Emails
IMAP or
POP3
Sesame Sesame Sesame
Publications
GoogleScholar,Bibster
Network analysis
Web application
RDF storage
Sesame
Metadata enrichment (Identity reasoning, geographic lookup)
Interoperability (1)
Interoperability on the knowledge level =
syntax + semantics + context Syntax
Easy (but a ‘forgiving’ parser would be nice)
Semantics Doable: shared ontologies, ontology mapping (e.g. for
foaf:interests), unique object identification (e.g. for foaf:Person),
Context Challenge
Interoperability (2): Context
Provenance: where the information comes from, when was it collected?
Time-to-live: how long is it going to stay valid?
Trust and ratings: is it considered trustworthy (by someone), is it important (for someone)?
Security: who can access it and how? …
Interoperability (3):Process
How do we find each other? Registries vs. pointers
How do we exchange? Connectivity Protocol (e.g. subscriptions vs. advertizements)
What do we exchange? Files, access etc.
Why would we exchange? The economics
Flink and the FOAF-web
Flink interoperates with the FOAF-web Producer and consumer of FOAF data But: 762 other definitions of Person (
www.swoogle.org), including swrc:Person FOAF-web is the kind of nightmare the SW
promises to be Open, decentralized system Distributed data and services Issues of syntax and semantics Lack of authority, privacy etc.
Flink and the FOAF-web (2)
Majority of files are incorrect XML, RDF or FOAF Errors from the obvious to the sneaky e.g. <foaf:mbox_sha1sum /> Ignore
FOAF extensions What to do with them? Ignore on import, don’t export
FOAF interests? A ‘loose end’ in FOAF (like dc:Creator) Ignore (on import)
Who is right? Let the user decide
How to contact Dan Brickley?
Summary
Interoperability is a challenge: Knowledge: syntax + semantics + context Process
Interoperability is about coming to an agreement Realize the trade-off between level of
commitment vs. scale