摘要：In order to ensure the established mobile Ad hoc networks against unauthorized user access, we need the identity authentication of the nodes in the network.Using the password for remote authentication in network is more and more attractive. This paper analyzes the remote password authentication scheme based on threshold in Ad hoc network, which is proposed by Chai. We find that the scheme cannot prevent passive attacks, counterfeit attack, and server spoofing attacks. Combining advantages of the broadcast encryption and password, we propose a new improved scheme to solve the security vulnerabilities of passive attack, and to improve the performance of the original scheme security. The scheme obtains many merits:1) it overcomes the passive attack. 2) it can resist the impersonation attack, and the server spoofing attacks.3) it can prevent the user password from being modified.4) it can implemente the identity authentication of nodes, and has better calculation performance
