Semantic Web services has been a vigorous technology research area for
about six years, producing a great deal of innovative work. In this
Part 2 'Trends & Controversies' installment, the authors continue
exploring the state of the art, current practices, and future directions
for Semantic Web services. SWS aims to bring Semantic Web technology --
for representing, sharing, and reasoning about knowledge -- to bear in
Web service contexts. The objective is to enable a fuller, more flexible
automation of service provision and use and the construction of more
powerful tools and methodologies for working with services. The
introduction [Part 1] includes references for major SWS initiatives,
such as SAWSDL, OWL-S, WSMO, SWSF, and the Internet Reasoning Service.
Part 1 also includes essays by Michael L. Brodie and Frank Leymann that
discuss service technology needs from a long-term industry perspective.
This issue concludes with four more essays. The first two essays are
primarily concerned with nearer-term directions -- steps that will let
us build out from the current state of the art toward greater adoption
and applicability of SWS approaches. Amit Sheth lays out a near-term
roadmap of steps that will be essential for industry acceptance of SWS
approaches, starting from SAWSDL and current industry practice. He
counsels that essential steps are required to make SWS approaches
sufficiently accessible and economically attractive to industry. Steve
Battle starts with an analysis of OWL-S's strengths and limitations.
He then discusses the necessary evolution of business ontologies for
SWS. Along with the evolution of business practices, this will allow
for Web services and SWS approaches to come together. The final two
essays put forward longer-term agendas for the evolution of SWS. Katia
Sycara argues that SWS could benefit from decoupling itself from the
basic stack of Web service standards rather than following a more
incremental trajectory tied to their evolution. She also identifies
two important opportunities in which this strategy could pay off.
Dieter Fensel takes a broad perspective, arguing that the
characteristics of Internet-scale service usage, and problem solving
in general, call for an entirely new conceptualization of some of the
core challenges of computer science for the 21st century.