CTrust: Trust Management in Cyclic Mobile Ad Hoc Networks

Abstract

Mobility model and network topology play important roles in mobile ad hoc networks (MANETs). Most existing trust and reputation management systems in a MANET do not address mobility issues adequately. In this paper, we study the trust management problem in a MANET with cyclic movement patterns. In a cyclic MANET (cMANET) where nodes periodically move, we formulate trust management problems and propose the cTrust scheme to handle trust establishment and aggregation issues. Unlike trust management in conventional schemes, trust management in cMANET involves not only neighbor trust relationships but location and time factors as well. We model trust relations as a trust graph in cMANET to enhance accuracy and efficiency of trust establishment among nodes. Leveraging the distributed Bellman-Ford algorithm and stochastic Markov chain process for fast and lightweight aggregation of trust scores, the cTrust scheme is a decentralized and self-configurable trust aggregation scheme. To evaluate the performance, we implement the proposed cTrust scheme. We use the student contact patterns on the National University of Singapore (NUS) campus and Seattle metro bus traces as case studies for our cMANET communication model. The simulation results demonstrate the features of trust relationship dissemination in real environments and the efficiency, accuracy, scalability, and robustness of the cTrust scheme. With increasing scales of ad hoc networks and complexities of trust topologies, cTrust scales well with marginal overheads.