Secure Node Discovery in Ad-hoc Networks and Applications 1

Designing secure protocols over ad-hoc networks has proved to be a very challenging task, due to various features of such networks, such as partial connectivity, node mobility, and resource constraints. Furthermore, their lack of physical infrastructures deprives their users of even basic network functions such as message routing, for which nodes are themselves responsible.In this paper we consider a very basic network function, node discovery, in ad-hoc networks, where a node with limited network information would like to establish a session with a given number of other nodes in the network (of which the node may not be aware about). We formally define correctness, security and efficiency properties of node discovery protocols, and investigate the problem of designing such protocols under appropriate network topology assumptions. Here, the security of these protocols is against Byzantine adversaries that can corrupt up to a limited number of nodes in the network and make them arbitrarily deviate from their protocol. After presenting some secure node discovery protocols, we show their application to secure service architectures in ad-hoc networks.