Abstract
Efficient query answering over Description Logic (DL) ontologies with very large datasets is becoming increasingly vital. Recent years have seen the development of various approaches to ABox partitioning to enable parallel processing. Instance checking using the enhanced most specific concept (MSC) method is a particularly promising approach. The applicability of these distributed reasoning methods to typical ontologies has been shown mainly through anecdotal observation. In this paper, we present a parallelizable, enhanced MSC method for the answering of ABox conjunctive queries, using a set of syntactic conditions that permit querying of large practical ontologies in reasonable time, and combining it with pattern matching to answer queries over role assertions. We also present execution time and efficiency of an implementation deployed over computing clusters of various sizes, showing the ability of the method to process instance checking for large scale datasets.