Xacml Policy Optimization Algorithm Based On Venn Diagram

This paper proposes an XACML (Extensible Access Control Markup Language) policy optimization algorithm to increase the efficiency of policy evaluation, which is based on the Venn graphic method of set theory. A three layer structure model for XACML is constructed. The policies and rules in the layers are mapped into sets and expressed with the Venn diagrams. According to the decision result of each layer and by setting the combining algorithm priority, the conflicts and the redundancies among access control policies and rules are detected and eliminated based on the intersection and union relations between sets. Experimental tests carried under the main evaluation engines show that the algorithm can decrease the evaluation time effectively and reduce the memory space occupancy as well.