Byzantine Resilient Protocol for the IoT

Wireless sensor networks, often adhering to a single
gateway architecture, constitute the communication backbone
for many modern cyber-physical systems. Consequently, faulttolerance
in CPS becomes a challenging task, especially when
accounting for failures (potentially malicious) that incapacitate
the gateway or disrupt the nodes-gateway communication, not
to mention the energy, timeliness, and security constraints demanded
by CPS domains. This paper aims at ameliorating the
fault-tolerance of WSN based CPS to increase system and data
availability. To this end, we propose a replicated gateway architecture
augmented with energy-efficient real-time Byzantineresilient
data communication protocols. At the sensors level, we
introduce FT-TSTP, a geographic routing protocol capable of
delivering messages in an energy-efficient and timely manner
to multiple gateways, even in the presence of voids caused by
faulty and malicious sensor nodes. At the gateway level, we
propose a multi-gateway synchronization protocol, which we call
ByzCast, that delivers timely correct data to CPS applications,
despite the failure or maliciousness of a number of gateways. We
show, through extensive simulations, that our protocols provide
better system robustness yielding an increased system and data
availability while meeting CPS energy, timeliness, and security
demands.