Term rewriting for describing constrained policy graph and conflict detection

Constrained policy graph (CPG) is an imaginative graph and is in a high level understanding in comparison with pure logic. In this model we can describe the policies in constrained form according to the related system. In addition to the ability of describing ACPs, CPG model is able to combine policies and analyze them in order to detect possible conflicts arising from ACPs combination. Term rewriting systems are practical systems used in different fields including automatic theorem proving and developing computational models. Using term rewriting can help us in formal description and verification of access control policies (ACPs) and models. In this article after expression of how policies are described, their combination and conflict detection in CPG model, we describe them using term rewriting rules. These rules are appropriate tools for the automatic analysis of policies and conflict detection after their combination.