On The Evaluation Of Reputation And Trust-Based Schemes In Mobile Ad Hoc Networks

In multihop networks such as mobile ad hoc networks selfish or misbehaving nodes can degrade network performance. Reputation and trust-based schemes have been proposed in order to enforce cooperation and to discourage misbehaving nodes. These schemes detect and isolate selfish nodes and maintain network throughput by enabling nodes to construct paths that only include good nodes. In order to punish selfish nodes and restrict their services, selfish nodes are not provided with packet forwarding services anymore by the good nodes in the network. The aim of these schemes is to increase good nodes' benefit (throughput and utility) and to decreasemalicious nodes' benefit. In this paper, we demonstrate that the commonly adopted simulation parameters used by the research community for the evaluation of reputation or trust-based schemes in mobile environments usually produce biased results. We further demonstrate this fact by adopting a widely used reputation-based scheme as our case study using the commonly used metrics, such as throughput, utility, delay, and overhead. The simulation parameters are analyzed analytically and via simulations in order to demonstrate their main reason of producing inaccurate and biased results. Finally, we compare simulation and analytical results to corroborate our claim and discuss how to mitigate the resulted inaccuracy and biasness. Copyright (C) 2015 John Wiley & Sons, Ltd.