Memory attestation of wireless sensor nodes through trusted remote agents

Wireless sensor networks (WSNs) have been deployed in various commercial, scientific, and military applications for surveillance and critical data collection. A serious threat to sensor nodes is malicious code injection attack that results in fake data delivery or private data disclosure. Memory attestation used for verifying the integrity of a device's firmware is a promising solution for detecting an infected sensor node; particularly, low-cost software-based schemes are suitable for protecting resource-constrained sensor nodes. However, a software-based attestation usually requires some additional mechanisms for providing reliable integrity evidence when the sensor nodes communicate with the verifier through a multihop setting. Alternative hardware-based attestation (e.g. trusted platform module) ensures a reliable integrity measurement that, however, is impractical for certain WSN applications primarily because of the high computational overhead and high hardware cost. The authors propose a lightweight hardware-based memory attestation scheme against the malicious code injection attack, and the proposed scheme employs a lightweight tamper-resistant hardware security module, which is free from any complicated cryptographic computation and is particularly suitable for low-cost sensor nodes. In addition, experimental results demonstrating the effectiveness of the proposed scheme are presented.