Vis-a-Vis : Privacy for Location-Based OSNs

Online social networks (OSNs) are immensely popular, but their centralized control of user data raises important privacy concerns. This paper presents Vis-„a-Vis, a decentralized framework for OSNs based on the privacy-preserving notion of a Virtual Individual Server (VIS). A VIS is a personal virtual machine running within a paid compute utility. In Vis-„a-Vis, a person stores her location data on her own VIS, which arbitrates access to that data by others. VISs self-organize into overlay networks corresponding to social groups with whom their owners wish to share location information. Vis-„a-Vis uses distributed location trees to provide efficient and scalable operations for creating, joining, leaving, searching, and publishing data to these groups. We have evaluated our Vis-„a-Vis prototype in the Amazon EC2 compute utility. Our results demonstrate that Vis-„a-Vis represents an attractive complement to today’s centralized OSNs.