Date Added: Apr 2011
Social networking platforms such as Facebook, MySpace, Twitter, and many others have seen an enormous increase in user population and user provided information. However, users are increasingly concerned about identity and data privacy since information is aggregated at single companies. To address this issue researchers have been investigating alternative solutions, where the users' data such as 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.