Cryptanalysis and Improvement of a Group Authentication Scheme with Multiple Trials and Multiple Authentications

الملخص EN

Authentication is one of the most fundamental services in cryptography and information security.

Compared with the traditional authentication methods, group authentication allows a group of users to be authenticated at once rather than authenticating each of these users individually.

Therefore, it is more desirable in the group oriented environment, such as multicast/conference communications.

In this paper, we first demonstrate that a recent group authentication scheme by Chien (Security and Communication Networks, 2017) suffers some security flaws, i.e.

an adversary in the asynchronous communication model can pretend to be a legitimate group member without being detected.

We then use the Anonymous Veto Networks (AV-net) to patch Chien’s scheme, so that its security can be rigorously proved in a well-defined security model.