John S. Baras

2006

On Trust Models and Trust Evaluation Metrics for Ad-Hoc Networks

G. Theodorakopoulos, J. S. Baras

Journal of Selected Areas in Communications, Security in Wireless Ad-Hoc Networks, Vol. 24, Number 2, pp. 318-328, February 2006. [2007, IEEE Communications Society Leonard G. Abraham Prize]

Full Text Paper ( .Pdf )

Abstract

Within the realm of network security, we interpret the concept of trust as a relation among entities that participate in various protocols. Trust relations are based on evidence created by the previous interactions of entities within a protocol. In this work, we are focusing on the evaluation of trust evidence in ad hoc networks. Because of the dynamic nature of ad hoc networks, trust evidence may be uncertain and incomplete. Also, no preestablished infrastructure can be assumed. The evaluation process is modeled as a path problem on a directed graph, where nodes represent entities, and edges represent trust relations. We give intuitive requirements and discuss design issues for any trust evaluation algorithm. Using the theory of semirings, we show how two nodes can establish an indirect trust relation without previous direct interaction. We show that our semiring framework is flexible enough to express other trust models, most notably PGP’s Web of Trust. Our scheme is shown to be robust in the presence of attackers.

Biography | Site Map | Contact Dr. Baras | Send Feedback | ©2005 ISR