Sharif Digital Repository

One of the security issues in data outsourcing scenario is the enforcement of data owner’s access control policies. This includes three challenges; 1) the average number of keys needed to access authorized resources, 2) efficient update of policies, and 3) confidentiality of data owner’s access control policies. Most of the existing proposed solutions address only one of these challenges, while they impose high overhead on both the data owner and users. Such an overhead prevents the model to be implemented in practical applications. In this thesis, we propose an approach to address all the aforementioned challenges with acceptable overhead. In this approach, which is based on selective...