CAST: Context-Aware Security and Trust framework for Mobile Ad-hoc Networks using policies

Due to lack of pre-deployed infrastructure, nodes in Mobile Ad-hoc Networks (MANETs) are required to relay data packets for other nodes to enable multi-hop communication between nodes that are not in the radio range with each other. However, whether for selfish or malicious purposes, a node may refuse to cooperate during the network operations or even attempt to interrupt them, both of which have been recognized as misbehaviors. Significant research efforts have been made to address the problem of detecting misbehaviors. However, little research work has been done to distinguish truly malicious behaviors from the faulty behaviors. Both the malicious behaviors and the faulty behaviors are generally equally treated as misbehaviors without any further investigation by most of the traditional misbehavior detection mechanisms. In this paper, we propose and study a Context-Aware Security and Trust framework (CAST) for MANETs, in which various contextual information, such as communication channel status, battery status, and weather condition, are collected and then used to determine whether the misbehavior is likely a result of malicious activity or not. Simulation results illustrate that the CAST framework is able to accurately distinguish malicious nodes from faulty nodes with a limited overhead.