Using Bell States Between The Two Key Distribution Network Of Quantum Key Distribution Protocol

At information age, the material, energy, information are three major resources that the mankind depends on for existence. Quantum information is a new subject that is combination of information science and quantum mechanics. It involves a lot of disciplines, such as physics, communication, computer, mathematics, etc... Quantum characteristic has unique function among information field, it might exceed classical information theory in many aspects, if quantum mechanics is applied to information science, a new discipline arises, and that is quantum information. This discipline based on quantum mechanics, includes several aspects, such as quantum key distribution, quantum communication and quantum computer, etc... It has made great progress on the theory and experiment in recent years. The development of quantum information has offered the reliable. physics foundation for the change of information science in the future, and new principle, method in the development in the 21st century for information science.With the development of quantum computation, the most important classic cryptographic scheme named public-key crypto-system will be aggressed easily. The principle of the quantum mechanics can only help to make the key distribution secure. In section II, we present a theoretical quantum key distribution scheme using EPR pairs. In this scheme, we can ensure the communications in security and detect Eve requires the comparison of few bits.All of the users must transmit the source of key to the center before distributing the key in the network. In the environment of network, the center must be true heartedness that the users can get the secret key in security. Then based on network, using the quantum store and quantum entanglement swapping, we realize the distant quantum key transmission under many users of many centers.