Exposed-mode of Wormhole Attack in Opportunistic Mobile Networks: Impact Study and Analysis

Wormhole attack has exposed-mode (internal attack with exposed attacker nodes identities) and hidden-mode (external attack with hidden attacker nodes identities). In exposed-mode, the pair-wise connected attacker nodes fool the legitimate nodes by using a hidden link to route packets and yield high packet delivery ratio. As the packets reach the wormhole nodes, attackers can initiate traffic analysis, packet dropping, and/or packet modification attacks. This paper studies and analyzes the impact of the exposed-mode of wormhole attack in Opportunistic Mobile Networks (OMNs) and the parameters affecting it. The impacts of the exposed-mode of wormhole attack are analyzed using the amount of extra routed packets the attacker nodes will obtain. The attack was launched by varying different parameters (i.e., number of wormhole nodes, attack frequency, and attack duration) that influence its intensity against four main routing protocols in OMNs (i.e., Prophet, Spray and Wait, Epidemic, and First Contact). The simulation experiments employed two widely-used mobility traces (real-world and synthetic) in OMNs and were analyzed in terms of the most vulnerable routing protocol and the most influential attack parameter. We concluded that attackers can smartly overthrow safe communications in OMNs using deep analysis of routing mechanisms and nodes density.