Cryptographic Protocols And Algorithms In Quantum Information Theory In The Study

The combination of quantum mechanics and classical information theory yields the new subject of quantum information theory. Quantum mechanics is the foundation of quantum information, which primarily study quantum information processing, including quantum computer, quantum communication and quantum key distribution. When we applied the properties of quantum mechanics to information, classical limit of information theory could be exceeded in many ways, and we can accomplish many unimaginable tasks for classical information processing, such as fast factoring, absolutely secure cryptograph etc. Quantum Cryptography is an important application of quantum information. Using the miraculous properties of quantum mechanics Quantum Cryptography breaks thought the confines of classical encryption and can make our communications perfectly secure. In the past several years, there has been significant progress in Quantum Key Distribution (QKD). Many QKD experiments have been successfully demonstrated in the free space and in the optical fiber. In the paper,all kinds of QKDs have been summarized and their security have been discussed. All classic signature schemes are based on some complex problems, so they can not provide absolute security. In the paper, a new signature scheme based on quantum cryptography has been proposed and the scheme is provable secure. The scheme uses a public board and can recovery message, provides confidentiality of the message and a higher efficiency in transmission. Finally a thought of software design on the quantum signature scheme has been provided and main flow charts have been drawn.