Method for distributing key

Abstract

The present invention relates to a key distribution method which comprises the following steps: 1) respectively generating a pair of temporary public / private key pair by a first entity and a second entity which requires communication; and 2) through the public / private key pairs respectively generated by the first entity and the second entity, applying to a key distribution center to obtain a communication conversation key. The invention is based on a ternary equal identification (TePA) and adopts a public key cryptographic technique for distributing key to the entity which needs communication through the key distribution center KDC. The safe distribution and dynamic upgrading of the communication key are realized. A perfect forward security PFS is furthermore provided. The method settles the problems of considerable keys managed in the key distribution center, long storing period of the key by the user and no forward security of the communication key in the traditional method. The invention can be applied for the mobile communication network system and other communication system.

Description

technical field [0001] The invention relates to a key distribution method, in particular to a key distribution method based on a key distribution center. Background technique [0002] When secure communication is required between communication network entities, key management is one of the key technologies. Sharing a key per pair of users is possible in small networks, but is not feasible in larger networks. In a system with N users, in order to realize secure communication between any two users, N(N-1) / 2 keys need to be generated and distributed to ensure secure communication between any two users in the network. As the scale of the system increases, the complexity increases dramatically. For a network where N is 1000, about 500,000 keys are needed for distribution, storage, etc. In order to reduce complexity, a centralized key management method is usually adopted, which is implemented by a trusted online server as the key distribution center KDC (Key Distribution Center)...

AI Technical Summary

Problems solved by technology

[0005] Due to the participation of the key distribution center or key transfer center, each pair of entities can use a fresh communication key each time they communicate, but each user needs to save a shared key with the key distribution center or key transfer center. The secret management key is used for a long time, and for the key distribution center and the key transfer center, it not only needs to store a huge number of secret management keys, but also bears a large security risk, because once there is a problem, it will directly Threat to the security of the entire system, and none of the above-mentioned key distribution methods has the perfect forward secrecy PFS (Perfect Forward Secrecy) of the key

Images