A key agreement protocol using mutual authentication for ad-hoc networks

Security is the major concern on designing a communications network. As for ad-hoc networks, the security problem is much more complicated than that of conventional networks. In this paper, the problem of securely generating and distributing a group key to group members of an ad-hoc network is addressed. A key agreement protocol using mutual authentication is proposed. The idea of using the XOR operator suggested in a previous study is adopted. By using mutual authentication, the proposed protocol prevents both replay attack and password-guessing attack, which are two potential problems in the previous study. To further enhance security, a rekeying mechanism is introduced for updating the group key if there were no changes in group members. Both security and complexity analyses show that the proposed protocol is not only securer but also more efficient than other well-known key agreement protocols.