With in-network sensor data storage and query, storage nodes are responsible for storing the data collected by sensor nodes and answering queries from users. Thus, without proper protection for data types and user queries, compromise of storage nodes and/or sensor nodes may reveal sensitive information about the sensed environment as well as users' private interests and query patterns. In this paper, we explore trade-offs between privacy, computation overhead, communication overhead, network flexibility and network complexity, and propose ElliPS (Elliptic curve based Privacy Scheme) to provide joint protection on data type privacy and query privacy in the presence of sensor node compromise, storage node compromise, or under collusive attacks by compromised sensor nodes and storage nodes together. Extensive analysis and simulation are conducted to verify the security properties and efficiency of the proposed scheme.

Mobile devices like laptops, iPhones and PDAs are highly susceptible to theft in public places like airport terminal, library and cafe. Moreover, the exposure of sensitive data stored in the mobile device could be more damaging than the loss of device itself. In this work, we propose and implement a