Introduction - If you have any usage issues, please Google them yourself
1, the realization of a centralized allocation of symmetric key (for communication between the parties A and B, respectively, and the KDC already has a session key) 2, Distributed symmetric key distribution (as communications between the parties A and B have to share a session master key) 3, public key cryptographic techniques to achieve symmetric cryptography key distribution (for communication between the parties A and B have each other' s public key)