In unattended wireless sensor networks, data are stored locally and retrieved on demand. To efficiently transmit the collectorpsilas retrieval results, data are aggregated along being forwarded. The data confidentiality and integrity should be protected at the intermediate nodes. End-to-end encryption or hop-by-hop encryption based schemes are not efficient. Straightforward homomorphic encryption based scheme is not compromise resilient. To achieve all the desires, we propose a scheme - H2S by making use of both homomorphic secret sharing and homomorphic encryption. The security and efficiency of our scheme are justified by extensive analysis.

In In-networking storage Wireless Sensor Networks, sensed data are stored locally for a long term and retrieved on-demand instead of real-time. To maximize data survival, the sensed data are normally distributively stored at multiple nearby nodes. It arises a problem that how to check and grantee data integrity of distributed data storage in the context of resource constraints. In this paper, a technique called Two Granularity Linear Code (TGLC) that consists of Intra-codes and Inter-codes is presented. An efficient and lightweight data integrity check scheme based on TGLC is proposed. Data integrity can be checked by any one who holds short Inter-codes, and the checking credentials is short Intra-codes that is dynamically generated. The proposed scheme is efficient and lightweight with respect to low storage and communication overhead, and yet checking validity is maintained. Our conclusion is justified by extensive analysis.