FlexiCast: Energy-Efficient Software Integrity Checks to Build Secure Industrial Wireless Active Sensor Networks

Industrial wireless sensor networks (IWSNs) are advancing to a form of active networks called industrial wireless active sensor networks (IWASNs) with reprogrammable sensor nodes, and thus require a method to check the integrity of software in sensor nodes. Regarding energy efficiency, however, previous methods did not take into account the scalability of IWASNs and thus performed inefficiently. In this paper, we propose FlexiCast, which presents a novel energy-efficient method to check the integrity of software objects. Sensor nodes can efficiently detect a modification in software objects sent by a base station or stored in neighboring nodes through authenticated fingerprints and network-wide attestation. Our analysis shows that FlexiCast can reduce energy consumption by 71% for both updating software objects and checking modifications regarding more critical attacks.