An approach to evaluate policy similarity

Abstract

Recent collaborative applications and enterprises very often need to efficiently integrate their access control policies. An important step in policy integration is to analyze the similarity of policies. Existing approaches to policy similarity analysis are mainly based on logical reasoning and boolean function comparison. Such approaches are computationally expensive and do not scale well for large heterogeneous distributed environments (like Grid computing systems). In this paper, we propose a policy similarity measure as a filter phase for policy similarity analysis. This measure provides a lightweight approach to pre-compile a large amount of policies and only return the most similar policies for further evaluation. In the paper we formally define the measure, by taking into account both the case of categorical attributes and numeric attributes. Detailed algorithms are presented for the similarly computation. Results of our case study demonstrates the efficiency and practical value of our approach. Copyright 2007 ACM.