Description

Users and resources in online social networks are interconnected via various types of relationships. In particular, user-to-user relationships form the basis of the OSN structure, and play a significant role in specifying and enforcing access control. Individual users and the OSN provider should be enabled to specify which access can be granted in terms of existing relationships. In this paper, the system propose a novel user-to-user relationship-based access control model for OSN systems that utilizes regular expression notation for such policy specification. Access control policies on users and resources are composed in terms of requested action, multiple relationship types, the starting point of the evaluation, and the number of hops on the path. The system present two path checking algorithms to determine whether the required relationship path between users for a given access request exists. The system validate the feasibility of our approach by implementing a prototype system and evaluating the performance of these two algorithms. The notion of compactness of a social group is particularly relevant. While the literature usually refers to compactness as a measure to merely determine how much members of a group are similar among each other. Trust has profound effects on the dynamics of group formation and their evolution. Based on the requested action and the relationship types in online social networks are represented in regular expression notation. The system propose a quantitative measure of group compactness that takes into account both the similarity and the trustworthiness among users.