Abstract: Because of the inherent characteristics in the Ad oc wireless network, the centralized authentication services provided by CA in traditional networks is not suitable for this network. In this paper, we apply the threshold digital signature scheme based on the discrete logarithm to distribute the authentication services into the whole network, so that each individual node can potentially provide other nodes with certification services. The scheme not only localizes the authentication service but also adapts to the scalability. At the same time, this scheme overcomes the limit to other distributed certification services which need to trusted party in the system initialization phase.

Key words: Ad Hoc network, threshold digital signature scheme, authentication service