Efficient Entity Authentication Using Modified Guillou–Quisquater Zero-Knowledge Protocol

Abstract

Fiat and Shamir were the first ones to come up with the idea of proving a zero-knowledge scheme with the concept of knowledge about knowledge. However, their scheme required to be run for a considerable amount of time, so that the probability of a false claimant being correct is less. This meant greater computation cost. Taking inspirations and motivations from Fiat and Shamir, Guillou and Quisquater developed a scheme based on the same concept of knowledge about knowledge. Their scheme was based on the working of RSA, and it required to be run fewer number of times for attaining the same probability of a false claimant being correct. However, some shortcomings have been observed in Guillou–Quisquater’s scheme. In this work, we pointed out those shortcomings and tried to modify their scheme. The modified scheme is developed on the difficulty of Diffie–Hellman key exchange protocol. The proposed scheme also requires to be run for lesser number of rounds. We also performed the security analysis and performance analysis for the proposed scheme.