Gemstone: Empowering Decentralized Social Networking with High Data Availability

Social networking platforms such as Facebook, MySpace, and Twitter have seen a significant increase in user population and user provided information. However, users are increasingly concerned about identity and data privacy since information is controlled by single companies. To address this issue researchers investigated alternative solutions, where the users' data, e.g. profile information, comments and messages, is stored at user-controlled nodes. Although these solutions provide a plausible means for avoiding privacy leaking in central instances, they raise a new challenge to design a cost-effective storage replica scheme which ensures a high data availability even when some users are offline. In this paper we present Gemstone, a social network platform where the data replication scheme leverages a learning mechanism based on social relationships, online patterns of peers and user experiences. Our preliminary evaluation shows that compared to related works, it achieves higher data availability while requiring a smaller number of data replicas.