Asynchronous Group Authentication Based on Geometric Approach

Abstract

Individual authentication in air warfare is used to check whether a single participant is a legal member of the predefined group but not determine all participants at one time. An asynchronous (m, t, n) group authentication protocol is proposed based on multidimensional sphere reconstruction theorem of space analytic geometry without making any computational assumption, where m is the number of participants, t is threshold value, and n is the number of members. The proposed protocol can determine whether all participants belong to the predefined group at one time, which is applicable to batch verification prior to individual authentication. The center’s coordinate of (t-1)-dimensional sphere is treated as the shared secret and the coordinate of the point on the surface of the sphere, multiplied by a random blind factor, is issued to all members as their tokens. If m participants can reconstruct the shared secret by utilizing their tokens, indicate that there is not any invalid participant, otherwise perform individual authentication. Analyses show the proposed scheme can not only rule out the illegal outsider but also resist up to t-1 group member conspiring to forge a valid token for an outsider. In addition, compared with other schemes the proposed scheme is more applicable for air warfare network, with light-weight computation, flexible distribution, and high information rate.