Trust establishment in ad hoc and sensor networks

Ad hoc and sensor networks highly depend on the distributed cooperation among network nodes. Trust establishment frameworks provide the means for representing, evaluating, maintaining and distributing trust within the network, and serve as the basis for higher level security services. This paper provides a state-of-the-art review of trust establishment frameworks for ad hoc and sensor networks. Certain types of frameworks are identified, such as behavior-based and certificate-based, according to their scope, purpose and admissible types of evidence. Moreover, hierarchical and distributed frameworks are discussed, based on the type of ad hoc and sensor networks they are designed for. The review is complemented by a comparative study built both on criteria specific to each category and on common criteria, grouped into three distinct classes: supported trust characteristics, complexity and requirements, and deployment complexity and flexibility.