Site Interoperability Projects at DERI Galway's SW Cluster

John Breslin (for Stefan Decker) Site Interoperability Projects at DERI Galway‘s SW Cluster [email_address] www.johnbreslin.com Interop Issues in SW Sites 7 th February 2005

SW Cluster: Overview

SIOC: Semantically Interlinked Online Community

SemanticWeb.org

FOAFRealm

RDF Datasets for Site Exchange

SemanticWeb.org

FOAFRealm

SIOC: Introduction

Issues with online communities:

Data on community sites cannot be harnessed correctly

Isolated communities discussing complementary topics

Information is being repeatedly requested across sites

SIOC approach:

Ontology

Data Interface

Inferring Connections

SIOC: To Interconnect Bulletin Board Sites

boards.ie

boards.us

boards.jp

boards.geek.nz

SIOC: Ontology

Namespace at

rdfs.org/sioc/ns#

SIOC: Data Interface (galway +broadband +linux)

SIOC: Inferring Connections

SemanticWeb.org

FOAFRealm

SemanticWeb.org: Introduction

General interoperability considerations

The site

RDF/XML views of local data

Integration of remote data

Data access interface

Ontology import and export

Possible extensions

SemanticWeb.org: General Interop Considerations

Basic idea is to use Semantic Web technology to allow different web sites to „work together“

Interoperability could cover re-use and integration of other sites‘ models , data , and functionality

Presentation layer components (e.g. stylesheets for agreed-on RDF/XML structures) may be considered too

SemanticWeb.org: The Site

SemanticWeb.org will (soon again ;-)) be the Semantic Web community portal

The new (RDF-enhanced) site will provide information about Semantic Web events, people, tools, organisations, projects, and other related resources

Both instance data and model information can be added, modified, extended, and exported online

SemanticWeb.org: Architecture

SemanticWeb.org: RDF/XML Views of Local Data

Each portal object (page, channel, blog post, user, vocabulary, SKOS concept, resource description...) can be serialized as RDF/XML

Resource Description Discovery (RDD) will be enabled by <link /> tags in XHTML, HTTP headers (X-Metadata-Location) and support for URIQA‘s MGET

Direct serving of content-negotiated XHTML vs. RDF/XML is considered bad practice (URI overloading etc.), but HTTP redirects may be triggered on certain accept-headers instead

SemanticWeb.org: Integration of Remote Data

The site has an „Add URL“ feature to add remotely maintained sources to the portal

Information from remote sources will be updated via an RDF crawler (scutter)

The final RDF store (Andreas‘ YARS) is going to support HTTP PUT and POST for direct integration of data

SemanticWeb.org: Data Access Interface

The final portal is going to provide an HTTP-based query interface (probably SPARQL protocol/query language compliant)

Together with the portal‘s RDD features, it will be possible to retrieve Concise Bounded Descriptions (CBDs) of resources for re-use in other environments

SemanticWeb.org: Ontology Import and Export

The portal system has a built-in web-based vocabulary editor and publisher

RDFS and OWL term sets can be imported, mixed, and exported

Annotation properties are used to add machine-readable presentation information for classes (e.g. re-usable views or forms)

SemanticWeb.org: Administration Screenshot

SemanticWeb.org: Possible Extensions

Add support for functionality re-use (e.g. facilitated sign-up à la FOAFNet)

The views are currently generated via PHP code (ontology-guided, though)

For improved interoperability, it could make sense to completely separate the presentation layer from program code (e.g. by a stylesheet-like approach and by formally describing the way resource descriptions should be displayed)