Raytheon BBN Technologies

The Semantic Web employs a different data model than relational databases. A relational database stores data in tables (rows and columns) while RDF represents data as a directed graph of subject/predicate/object triples. Accordingly, a Semantic Web data store is often called a graph store, 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 an underlying relational database. However, the query performance of such implementations is generally 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 data structure does not take advantage of standard relational query optimizers.

Early in the Semantic Web's evolution, Raytheon BBN Technologies recognized this problem, and developed a high-performance graph store called "Parliament." The goal of 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 Raytheon BBN's Semantic Web applications. Parliament is based on DAML DB and has served as a core component of projects Raytheon BBN Technologies has performed for a number of intelligence agencies and within the Department of Defense.

Storage and Inference

Parliament is an open source knowledge base that implements a high-performance storage engine, compatible with the RDF and OWL standards. 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, 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 based on a set of inference rules to enrich query results.

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