Several studies have been conducted on how to manage key management in secure and effective key management model inmulticast based on Logical Key Hierarchy (LKH). The improvement model based on LKH are discusses in this paper together with Diffie Hellman (DH) algorithm as method for key distribution and result based on computation cost and performances also discussed through this paper. Simulation has been done to test performance of the model. It has beenobserved that performance process for improvement LKH gives better results in terms of speed, time and security indynamics communications