BBN Technologies

Data representation on the Semantic Web follows a different model from the usual relational database. A relational database stores data in tables (rows and columns), whereas the canonical Semantic Web representation is a directed graph, according to the RDF and OWL standards. As a result, a store of Semantic Web data is called a graph store - also known as a "knowledge base" or "triple store."

A relational database can store a directed graph, and in fact, many graph stores are implemented as a thin interface layer wrapping a relational database. However, the query performance of such implementations is usually poor. This is because the only straightforward way to store the graph with the required level of generality is to use a single table to store all the triples, and this schema tends to defeat relational query optimizers.

Early in the Semantic Web's evolution, BBN encountered exactly this problem, and so the graph store called "Asio Parliament" was born. The goal of Asio Parliament was to create a storage mechanism optimized specifically to the needs of the Semantic Web, and the result was a dramatic speed boost for BBN's Semantic Web programs. Since its initial conception, Asio Parliament has served as a core component of several projects at BBN at a number of intelligence agencies and within the Department of Defense.

Storage and Inferencing

Asio Parliament implements a high-performance storage engine that is compatible with the RDF and OWL standards. However, it is not a complete data management system. Asio Parliament is typically paired with a query processor, such as Sesame or Jena, to implement a complete data management solution that complies with the RDF, OWL, and SPARQL standards for data representation, ontology, and query, respectively.

In addition, Asio Parliament includes a high-performance SWRL-compliant rule engine, which serves as an efficient inference engine. An inference engine examines a directed graph of data and adds data to it based on a set of inference rules. This enables Asio Parliament to fill in gaps in the data automatically and transparently, inferring additional facts and relationships in the data to enrich query results.

The Asio Parliament knowledge base is a fundamental part of the Asio tool suite. Asio Parliament's high performance storage and inference capabilities enable Semantic Web applications to store data directly in the canonical Semantic Web format. In addition, Asio Parliament is fully compliant with all of the relevant Semantic Web standards. For more information, or to request a demo, please send inquiries to asio@bbn.com.