An improved secure and efficient sequential authentication scheme in delay tolerant networks

An ordered multi-signature scheme allows multiple users to sign the same message sequentially to generate a constant-size digital signature, which convinces the verifiers of not only the signers who have signed the message but also the order in which they signed. In some applications of wired/wireless networks, ordered multi-signature is always used to construct sequential authentication schemes. However, the emerging networks such as delay tolerant networks and vehicle ad-hoc networks make the conventional multi-signature schemes unavailable and insecure since the signer set is not determined at the beginning and the initiated signer can not receive the feedback from the co-signers due to the long delay and undetermined end-to-end connections. To solve the above problem, we give a general analysis of the previous schemes and list desirable properties of an ordered multi-signature scheme. We propose an improved secure and efficient sequential authentication scheme based on our proposed ordered multi-signature which could be proven secure in the registered key model with the helps of random oracle. Public key is short in our scheme which is suitable to the applications under current wireless networks.