Detecting node compromise in hybrid wireless sensor networks using attestation techniques

Node compromise is a serious threat in wireless sensor networks. Particular in networks which are organized in clusters, nodes acting as cluster heads for many cluster nodes are a valuable target for an adversary. We present two efficient hardware-based attestation protocols for detecting compromised cluster heads. Cluster heads are equipped with a Trusted Platform Module and possess much more resources than the majority of cluster nodes which are very constrained in their capabilities. A cluster node can verify the trustworthiness of a cluster head using the Trusted Platform Module as a trust anchor and therefore validate whether the system integrity of a cluster head has not been tampered with. The first protocol provides a broadcast attestation, i.e., allowing a cluster head to attest its system integrity to multiple cluster nodes simultaneously, while the second protocol is able to carry out a direct attestation between a single cluster node (or the sink) and one cluster head. In contrast to timing-based software approaches, the attestation can be performed even if nodes are multiple hops away from each other.