Research On Layered Multicast Security Implement And Packet Loss Control Technology

Layered multicast uses different transmission rates to meet the requirements of heterogeneous networks. It is an important solution of Multimedia data transmission. Congestion control is one of the key problems in Layered multicast.At first, this paper outlines the technologies in the existing IP Multicast and Multicast Congestion Control, and introduces the evaluation criteria and classification. Then focuses on the study of the layered multicast protocol.Then the paper presents a more general program of high-security layered multicast HSLM, congestion control protocol, under the condition of Router-Assisted congestion control. The edge router uses Router-Assisted access control algorithm RA-AC, which is on the basis of one-way function and Shamir Threshold Secret Shared Mechanism. It manages the group subscription so as to avoid user's self-benefic attacks. Analysis and simulation results show that the program can ensure real-time network traffic safety, and fair sharing of network bandwidth and better scalability and fairness.Finally, we analyze the reason of packets loss when switching shared tree to the shortest path tree occurring in layered multicast routing protocol. We propose improved solutions, and through simulation, we compare the advantages and disadvantages of several programs. The simulation results show that the zero-packets loss program can satisfactorily resolve the integrity of the data transmission in network, which also improves the reliability.