Private and secure service discovery via progressive approach in pervasive computing environments

The dynamic property of pervasive computing hinders users to have complete knowledge of the relationship among services, service providers, and credentials. The involvement of only the necessary users and service providers for service discovery in pervasive computing environments is challenging. Without prudence, users' and service providers' requests or service information, their identities, and their presence information may be sacrificed. The problem may be as difficult as a chicken-and-egg problem, in which both users and service providers want the other parties to expose sensitive information first. In this paper, we propose a progressive approach to solve the problem. Users and service providers expose partial information in turn and avoid unnecessary exposure if there is any mismatch. Although 1 or 2 bits of information are exchanged in each message, the theoretical analysis and experiments show that our approach protects sensitive information with little overhead.