The Research Of Key Management Of Hierarchical Multicast

Multicast is a new data transfer model. It has a very brilliant future. There's a more and more popular application in wireless network. Such as video frequency meeting, network game, video meeting and so on. IGMP that used to maintain group membership doesn't provide ability of access control. Anyone that got specified multicast address can join the group communication without any authorization and receive data packets. So it's necessary to encrypt all the data packets in those applications that require secure communication to prohibit non-authorized access. At the same time , because of the own property of wireless network, it's a more complicated schemes . Because of the secure problems in wireless network , this paper analyses and summarizes some exited group key management schemes, proposed a new scheme for multi-group data resources in wireless network.This paper introduces concepts of multicast key management firstly, it analyses some typical key management schemes and concepts of logical key management tree. And then we introduces some key management schemes in wireless network, and analyses its speciality complexity and the points when designed a new schemes. In the fourth chapter , based on exited key management schemes for multi-group data resources in wireless network, we proposed a new scheme to resolve redundancy key problems. It make a new key management tree which match the physical network topology, it can make a node in key tree only transmit those rekey it needs. Next making use of the partial-order relation between data resources in multicast communication and users, we can group these users and make these users with the same ordering relation into the same group, so we can unify many single key management tree to a tree. At the same time we provide the process of rekey of the new key management tree and the storage of users and the key distribute center. At last through data analyses we can see the new scheme obviously reduce redundancy key amount and communication cost because of the key updating.