Fairy Ring: Ubiquitous Secure Multiparty Computation Framework for Smartphone Applications

In this paper, we present a framework for secure multiparty computation on smartphones. Our framework provides protocols, which are constructed by additively homomorphic encryption, to guarantee security against semi-honest adversaries without collusion. The protocols made using our framework follow a client-server model, thus users of our framework can easily and jointly execute these protocols as a service by accessing a server using their smartphones. Our framework provides four primitive protocols, and application protocols are constructed by using these primitive protocols. Consequently, our framework provides an environment that allows non-experts to easily use and develop smartphone applications of secure multiparty computation. To demonstrate the practicability of our framework, we implement and execute voting on 16 smartphones.