SAFE: Policy Aware SPARQL Query Federation Over RDF Data Cubes

Abstract

Abstract. Several query federation engines have been proposed for accessing pub-lic Linked Open Data sources. However, in many domains, resources are sensitive and access to these resources is tightly controlled by stakeholders; consequently, privacy is a major concern when federating queries over such datasets. In this paper, we present SAFE, a SPARQL query federation engine that enables decentralised, policy-aware access to clinical information represented as RDF data cubes. We validate the performance of the system with experiments over real-world datasets provided by three clinical organisations as well as legacy Linked Datasets. In our evaluation, we show that SAFE enables granular graph-level access control over distributed clinical RDF data cubes and efficiently reduces the query execution time when compared with general-purpose SPARQL query federation engine. 1