CrowdShare: Secure Mobile Resource Sharing

Mobile smart devices and services have become an integral part of our daily life. In this context there are many compelling scenarios for mobile device users to share resources. A popular example is tethering. However, resource sharing also raises privacy and security concerns. In this paper, we present CrowdShare, a complete framework and its (Android) implementation for secure and private resource sharing among nearby devices. CrowdShare provides pseudonymity for users, accountability of resource usage, and the possibility of specifying access control in terms of social network relationships. The latter, denoted FoF Finder service, allows two devices, to determine in a privacy-preserving manner whether their owners are friends of each other or have common friends. FoF Finder service is an independent software module that encapsulates secure usage of privacy-preserving set intersection protocols. It is designed to be used easily by developers to secure other applications. Further, CrowdShare preserves secure connectivity between nearby devices even in the absence of the mobile infrastructure. We have implemented CrowdShare including FoF Finder service on Android devices and report good performance results and preliminary user evaluations.