Enhanced QKD protocol based on zero-knowledge proof and post-quantum signature

Quantum communication uses the principles of quantum mechanics to ensure information security. Quantum key distribution (QKD) transmits quantum states through optical fibers and is the most mature technology. Based on the non-cloning and uncertainty principles, it ensures that keys can be shared securely even in the face of quantum computers. BB84 is widely used due to its complete theory and simple fiber implementation, but it has limitations, such as the fragility of classical channels, which are susceptible to man-in-the-middle attacks and message tampering. To address the above problems, we proposed a new ZKP-Signature BB84 protocol, which uses Schnorr zero-knowledge proof to strengthen identity authentication, uses Dilithium post-quantum signatures to ensure the authenticity and integrity of messages, and improves security through classical channel reinforcement. Simulation results show that ZKP-Signature BB84 can resist a variety of attacks including man-in-the-middle attacks. This study provides new ideas for improving the security of QKD systems and expanding future systems, and helps to derive the further development of quantum communication technology.