Saphena: An Approach for Analyzing Similarity of Heterogeneous Policies in Cloud Environment

Analyzing similarity of access control policies is very important in many application sceneries, for example, conducting similarity analysis to reduce policy scale in cloud services composition, or through similar policies to find cloud services which have same function. Existing methods of policy similarity analysis are mainly based on logical reasoning or Boolean function comparison, which are computationally expensive and do not scale well for large heterogeneous distributed cloud environments. In this paper, we propose a lightweight approach for analyzing the similarity of heterogeneous policy in cloud environment, called Saphena. In Saphena, paired attributes are used to unify and simplify heterogeneous policies and the similarity of attribute is calculated by utilizing semantic-based analysis method. The similarity of policies is obtained by digging the similarities of all attributes in policies and controlling the corresponding weighting factor. We design a threshold that is used to judge whether similarity among policies. Cloud service providers can set threshold through interface flexibly based on their difference request. Comprehensive experiments have been conducted, which demonstrate the effectiveness of the proposed method by the comparison with the classic cosine similarity analysis arithmetic.