Resilience and security of opportunistic communications for emergency evacuation

We describe an autonomous emergency support system (ESS) based on opportunistic communications (oppcomms) to support navigation and evacuation of civilians in built environments. In our proposed system, civilians are equipped with low-cost human wearable devices that employ oppcomms to exchange packets at close range of a few meters with limited or no infrastructure. This paper investigates the resilience and performance of oppcomms in the presence of network attacks. We assume that a portion of nodes in the network have been compromised and misbehave, which adversely affects communications and evacuation. We evaluate the effect of three types of node misbehaviour and propose a defense mechanism against the most serious among these. The defense mechanism combines identity-based cryptography with collaborative malicious packet detection and blacklisting of detected attackers. Results from simulation experiments conducted on a specialized emergency simulator show the impact of misbehaviour on evacuation and communication performance and the improvement offered by the defense mechanism.