Modeling Key Agreement in Multi-Hop Ad Hoc Networks

G.Crescenzo, M. Striki, J. S. Baras

2006 International Wireless Communications and Mobile Computing Conference ,Vancouver, Canada, July 3 - 6, 2006.

Abstract

Securing multicast communications in ad hoc networks has become one of the most challenging research directions in the areas of wireless networking and security. This is especially true as ad hoc networks are emerging as the desired environment for an increasing number of civilian, commercial and military applications, also addressing an increasingly large number of users. In this paper we study a very basic security question for Ad Hoc Networks: Key Agreement against passive adversaries. Despite being a widely studied area in wired networks, the problem becomes significantly more challenging for ad hoc networks, and even more for sensor networks, due to lack of trusted entities, infrastructures, full connectivity, routing structures, and due to severe limitations on the resources and capabilities of network nodes. In this paper we perform a comprehensive investigation of Key Agreement over resource constrained ad hoc networks. First, we formally model the key agreement problem over multi-hop ad hop networks, and we directly extend known key agreement protocols for wired networks, and evaluate the efficiency of such approaches. We then go beyond natural extensions of such protocols, by proposing non-trivial extensions based on efficient topology-driven simulations of logical networks over an arbitrary physical network, in order to optimize the most significant metrics of interest for such networks: i.e. bandwidth, latency, processing cost. Indeed, the resulting protocols are significantly more efficient in some or all of the above metrics, as our analytical results indicate