BPKP based on Pairwise Key Pre-distribution key management scheme has implemented such functions as initial key-pair vectors distribution,the construction of communication key-pair vectors,and communication key-pair vectors updating.

Group rekeying is essential for large dynamic group security,especially for Internet multicast security,and batch rekeying is a focus among the high performance group security mechanism.

This paper puts forward a full new multicast rekeying scheme, the scheme combines batch rekeying and key rotation scheme together to enhance system’s security.

A new method of secure multicast rekeying based on hyperball;

Group rekey is triggered by the managers in the lower layer.

Research and implementation of group key management in batch group rekeying;

A Rekeying Algorithms for Dynamics Multicast;

A study of the batch rekeying for multicast security;

EAwLKHT:energy-aware multicast re-keying scheme in Ad Hoc networks;

Algorithms of Re-keying in Network & their Implementation;

While the efficiency of re-keying is a main factor that influences the performance of secure multicast, grouping keys into logical tree and re-keying for users change are effective ways to improve the efficiency of re-keying and reduce the burden of key management and network.

According to the key update algorithm used in this solution,updated keys.

And key update is one of the important problems in this subject.

The work process and the key update mechanism while members changed of the group key agreement based on tree and threshold scheme is concisely analyzed.