Cynics might call Semantic Web a technology looking for a solution. And they might have a point.
Semantic Web refers to a long-running World Wide Web Consortium (W3C) initiative that is working toward an ambitious — some might say hopelessly utopian — goal. At heart, it is a vision for how the World Wide Web should evolve to realize its full interoperability potential.
People vary widely in how they interpret the scope of the Semantic Web initiative. The tech industries are swarming with a wide range of projects, products, and tools that implement different variants of this vision. What vision is that? In the broadest sense, Semantic Web refers to an all-encompassing metadata, description, and policy layer that can, potentially, support universal, automatic, comprehensive, end-to-end interoperability across every macro or micro entity — including data, components, services, applications, and services — on every conceivable level.
Whew! If that’s not the working definition of “pie in the sky” or “boil the ocean” (pick your metaphor), I don’t know what is. In fact, I’m hard-pressed to refer to Semantic Web as a definable market or solution segment. However, it’s not entirely vacuous.
For starters, organizations can implement W3C-developed semantic description standards — such as Resource Description Framework (RDF) and Web Ontology Language (OWL) — to make the meaning of content unambiguously comprehensible to services, applications, bots, and other automated components. Second, there is a reasonably robust market for “ontology” tools to support RDF/OWL-based modeling of application semantics. Finally, there is some incremental adoption of these tools and concepts in established IT segments, such as:
- Enterprise content management (ECM): Semantic approaches can support more powerful discovery, indexing, search, classification, commentary, and navigation across heterogeneous stores of unstructured and semi-structured content. Semantic search — driven by concepts, not mere text strings — is regarded by some as a primary Semantic Web application. Indeed, many Semantic Web vendors are primarily implementing the technology in search engines that leverage ontology-based concepts to improve search accuracy and reduce spurious hits.
- Enterprise information integration (EII): Semantic approaches enable consolidated viewing, query, and update of structured data that has been retrieved from diverse sources. Indeed, most commercial EII environments present an abstract semantic layer that mediates access to heterogeneous data, such as enterprise resource planning and customer relationship management applications, converging to a common presentation-side schema. A handful of those EII vendors have begun to support Semantic Web standards, primarily through third-party software plug-ins.
- Enterprise service bus (ESB): Semantic approaches can facilitate multilayered application, process, and service interoperability across disparate environments. To date, there has been little production implementation of Semantic Web standards in the ESB arena, though some vendors have adopted semantics, ontologies, and RDF to describe the conceptual models implemented by application endpoints, agents, and intermediary nodes within ESB-like middleware approaches such as event stream processing.
But Semantic Web approaches are still on the periphery of these markets. 10+ years into its inception, Semantic Web still has no clear killer app. It’s not clear if or when that app will emerge.