A Novel Threshold Conference-Key Agreement Protocol Based on Generalized Chinese Remainder Theorem

The conference-key agreement protocol is a mechanism for generating a common session key among the authorized conference members. The common session key is used to encrypt communication messages transmitted over an open network. Inspired by traditional key agreement protocols and threshold cryptosystems, we have proposed a novel threshold conference-key agreement protocol in this paper. In the proposed protocol, we used a secret sharing scheme based on the generalized Chinese remainder theorem (GCRT) to achieve the threshold characteristic, and we can alter the shared data by adjusting an additional parameter k of the GCRT. If the number of conference members involved in generating the conference key exceeds a certain number, the members can cooperate to generate a valid common session key that also can be verified and used by other authorized conference members. Compared with traditional key agreement protocols, the proposed protocol has some unique characteristics that are beneficial in real applications.