Semantic Web Standardization in Europe: SWAD-Europe
by Dan Brickley, Libby Miller and Kate Sharp
The SWAD-Europe project nears completion. SWAD-Europe (Semantic Web Advanced Development in Europe) is a five partner collaborative EU project, part of the Information Society Technologies programme within the 5th Framework. The project has considerably contributed to the to the evolution of the Semantic Web.
SWAD-Europe originated within W3C's Semantic Web Activity, extending the approach taken in previous SWAD work at Massachusetts Institute of Technlolgy to focus on collaborative work undertaken alongside the World Wide Web Consortium's RDF (now Semantic Web) Interest Group. While the project is about and in support of W3C's Semantic Web Activity, it is managed independently. The project was created to complement and feed into 'standards track' work within the World Wide Web Consortium (W3C). SWAD-Europe is a collaboration between the World Wide Web Consortium in Europe, hosted by ERCIM, research institutions at CCLRC and the University of Bristol (ILRT), and the companies Stilo International Plc and Hewlett-Packard Ltd.
The Original Idea
SWAD-Europe was designed to support W3C's Semantic Web initiative in Europe, providing targeted research, demonstrations and outreach. The aim was to support the development and deployment of W3C Semantic Web specifications through implementation, research and testing activities. This involved finding and maintaining a balance between "in-house" Open Source tool development, community building, outreach and evangelism, combined with research and analysis to support and field-test Semantic Web standards. In practice, this meant that more time was spent working with members of the Semantic Web Interest Group community than on in-house development work, since this approach helped establish a broader base for Semantic Web development than could be accomplished within a single European project. The Interest Group provided a forum that connected SWAD-Europe (and other SemWeb-themed projects, from Europe and elsewhere) to the more formal standardisation activities of the W3C.
SWAD-Europe's work is best understood in the context of the challenges facing the RDF project in the 1997-2001 period prior to the creation of the Semantic Web Activity at W3C. In RDF's early years, a number of difficulties needed addressing. At that time, RDF technology was perceived by some as complex and overambitious, with poorly formalised specifications. Software tools were relatively immature, with toolkit-specific APIs and query languages, which meant that application code was often tightly bound to a specific RDF toolkit. The relationship between RDF and XML in terms of both tools and standards was unclear. Despite the difficulties faced by RDF in this period, there was nevertheless a lot of enthusiasm from early adopters of RDF which emerged in the Interest Group. The design of the project was an attempt to find a way to use the structure of a European project to support both formal standardisation work at W3C, and the community fora (Interest Groups) which can provide a home for users of Web technology to share their experiences.
The project's initial workplan included work on reviewing and developing tools to access, store, search Semantic Web data, with the goal of motivating and informing future work on RDF query languages and APIs. Practical case studies and demos were proposed, especially in near term areas such as thesaurus systems and next-generation blogging tools. A fair number of workshops were included, to foster developer discussion on critical 'seed applications', eg image annotation, calendaring, social networking and geo/mapping work. In addition to these efforts, the project tried to emphasise the importance not only of standards-based technology, but on technology integration. We undertook work on linking XML to RDF, on schema languages, SVG, query, XForms and Web Services. In each case, there was the same underlying intent: to enter into dialogue with users of W3C technology and understand how their practical problems might be addressed through combing RDF approaches with other, perhaps better understood, standards-based methods. The goal, in effect, was to help demonstrate the basics of Semantic Web as a fast-maturing technology platform. Reports from each of these activity areas are available from the project Web site.
Before, During and After
Throughout SWAD-Europe, we sought to build on pre-existing work, in particular work which was conducted in public fora and was supported by freely available opensource implementations. Previous collaborative efforts (by the project partners and members of the broader community) were supported through SWAD-Europe and subsequently fed into more formal activities within W3C. This illustrates the project's general approach, which is to utilize W3C's Interest Group mechanism to bring collaborators together, test their ideas, and present the results of those collaborations in a form that can have a good prospect of adoption within the Working Group mechanisms of W3C.
What difference did SWAD-Europe make?
As always with such projects, some areas proved more rewarding than others, and the emphasis of the project evolved in response to successes and opportunities. A significant achievement of the project has been in the area of outreach and community-building. The SKOS (Knowledge Organisation Systems and the Semantic Web) work has helped to re-engage the digital library/thesaurus community. The ten workshops held as part of the project have attracted diverse participants from multiple countries and specialities, and from the research, Open Source and business communities. Other successful work in the project has included software development, in particular the leading opensource C implementation of RDF in Redland/Raptor; and well-crafted and appealing demonstrators in the areas of Semantic Blogging and Semantic Portals, showing that Semantic Web applications can be simple, practical and easy. The pragmatic 'walk before we run' focus of the project was appreciated both by Semantic Web sceptics and by enthusiasts. Project members have also made substantial contributions to the editing and chairing of the RDF Core standards, and later, helped to establish 'Semantic Web phase two' groups at W3C: the Data Access working group and the Semantic Web Best Practices and Deployment working group.
The overarching aim of the project was to provide, through all appropriate means, a body of answers to questions that had previously gone unanswered, and to foster grassroots communities within which such concerns are addressed. Amongst its many themes, SWAD-Europe provided detailed answers to developer questions about RDF query and storage (analysis of scalability issues; query languages; APIs), and human-oriented classification (SKOS for thesauri, bookmark sharing etc.; semantic blogging). The project's final workshop was on the theme of FOAF, Social Networking and the Semantic Web, and illustrated some of the strengths of the project, combining presentations from academic, commercial and opensource perspectives with active collaborative work on tools and applications.
One lesson from the project is that it is both important and rewarding to provide an environment where members of the larger community that surrounds W3C can interact and collaboratively explore the practical issues around Web technology. The formal work of the W3C is based on small, highly focussed Working Groups where individuals commit a lot of time to creating new Web standards. SWAD-Europe's primary contribution was to help create a supportive background environment for such work, by allowing a much larger number of geographically-dispersed individuals to participate (through email, IRC, workshops and the Web) in the Semantic Web initiative. The project was, in the Semantic Web scene, unique in its emphasis of the practical and Web aspects of 'Semantic Web' for a Web developer audience. The support that SWAD-Europe provided to the RDF and Semantic Web Interest Group was an important exploratory step towards a model for wider participation in Web standardisation work, showing that W3C's successful Working Group-led approach can be complimented by a broader participation model which allows individual researchers and implementors to make real contributions to the deployment of existing standards and to the creation of new ones. The challenge for the future is to work towards a Web in which all European research efforts contribute to the communities which underpin the evolution of Web standards.
Dan Brickley is on the technical staff of the World Wide Web Consortium, where he serves as chair of the Semantic Web Interest Group and as SWAD-Europe Project Director. Libby Miller is the Semantic Web Group Coordinator at ILRT, University of Bristol. Kate Sharp is Project Manager for SWAD-Europe at ILRT, University of Bristol. Groups interested in collaborating with W3C Europe on future Semantic Web-related projects are invited to contact Dan Brickley at email@example.com.
SWAD-Europe reports index: http://www.w3.org/2001/sw/Europe/reports/intro.html
SWAD-Europe project homepage: http://www.w3.org/2001/sw/Europe/