Privacy homomorphisms for social networks with private relationships

Rovira i Virgili University, Department of Computer Engineering and Mathematics, UNESCO Chair in Data Privacy, Av. Països Catalans 26, Tarragona 43007, Catalonia, Spain
Computer Networks (Impact Factor: 1.28). 10/2008; DOI: 10.1016/j.comnet.2008.06.017
Source: DBLP

ABSTRACT Enabling private relationships in social networks is an important issue recently raised in the literature. We describe in this paper a new protocol which offers private relationships allowing resource access through indirect relationships without requiring a mediating trusted third party (although an optimistic trusted third party is used which only acts in case of conflict). Thanks to homomorphic encryption, our scheme prevents the resource owner from learning the relationships and trust levels between the users who collaborate in the resource access. In this way, the number of users who might refuse collaboration due to privacy concerns is minimized. This results in increased resource availability, as the chances that certain nodes become isolated at a given period of time are reduced. Empirical evidence is provided about the proposed protocol being scalable and deployable in practical social networks.

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