TEREC: Trust evaluation and reputation exchange for cooperative intrusion detection in MANETs

Mobile ad hoc networks (MANETs) are particularly vulnerable to attacks from malicious nodes as the reliability of all communication and data exchange on the network depends on collaboration of participating network nodes. In order to strengthen overall mobile network security and avoid attack, malicious nodes should be detected and appropriate measures taken, e.g. exclusion from network communications. In order to effectively identify malicious nodes we propose a system for Trust Evaluation and Reputation Exchange for Cooperative intrusion detection in MANETs (TEREC). Each node should monitor its directly connected neighbour nodes and resulting measurements and trust information should be gathered and exchanged cooperatively between all network nodes. These measurements when combined with information from other nodes can construct a node reputation value representing the trustworthiness of a specific network node. We propose to split reputation information into two values: trust and confidence. This allows each node to successively determine the reliability of other nodes without the need or reliance on a static, pre-established trust infrastructure (e.g. digital certificates) which requires significant overhead and can not be recovered once compromised. TEREC is evaluated via simulation and its performance measured in the presence of an increasing amount of malicious nodes. Evaluation results show that a benign majority of nodes prevail over malicious attacking nodes as they are able to accurately classify network nodes based on reputation estimations.