Key agreement in ad hoc networks

We encounter new types of security problems in ad hoc networks because such networks have little or no support infrastructure. In this paper we consider one such problem: a group of people in a meeting room do not have access to public key infrastructure or third party key management service, and they do not share any other prior electronic context. How can they set up a secure session among their computers? We examine various alternatives and propose new protocols for password-based multi-party key agreement in this scenario. Our protocols may be applicable in other scenarios, too. We also present a fault-tolerant version of a multi-party Diffie-Hellman key agreement protocol which can be of independent interest.