Consensus-Based Detection of Malicious Nodes in Cooperative Wireless Networks

In a wireless network adopting a cooperative decode and forward protocol, malicious nodes may not forward packets when requested. In this letter we propose to exploit cooperation also to detect malicious nodes. Each node monitors other nodes' transmissions and apply an adaptive quickest detection (AQD) technique to form an opinion, which is however affected by channel fading. In order to reduce false alarms, opinions are merged with a consensus algorithm at a fusion center, which then blocks malicious nodes. The possibility that malicious nodes report false opinions in order to avoid of being detected is taken into account in the design of the consensus algorithm.