Research On Secure Group Communication System And Design Of Efficient Group Key Agreement Protocols

Most distributed collaborative applications rely on secure group communication to provide secure, uninterrupted services within acceptable data throughput and latency parameters. With the development of distributed collaborative application increasingly, this is difficult to guarantee security mechanisms in secure group communication which satisfied the requirements on data throughput and latency parameters of modern distributed collaborative applications currently, especially in complex network environment, although there are many researches on architecture and security mechanisms of secure group communication in recent years.This dissertation presents researches on secure group communication and its key techniques, which security techniques can be integrated into group communication systems to providing efficient communication, larger throughput and low latency. And main content, innovation, contribution and significance are as follows:Firstly, from the point of view of secure group communication system architecture, the deficiencies of system throughput and latency in secure group communication are presented. Considering these deficiencies, a general secure group communication scheme based on C/S model is developed. This scheme integrated security techniques into group communication by using distributed security idea. This scheme supports that dynamic join and leave of group member and every group member join other group. Compared with previous group communication systems, it makes a great progress in efficiency.Secondly, group key agreement is investigated and designed. A group key agreement protocol based on m-Tree and DH protocol was developed to improve the poor scalability and efficiency. This protocol reduces depth of key tree efficiently and computation cost by adopted m-tree and communication cost by every layer implemented key agreement protocol. It makes a great progress in applications of LAN and WAN at the same time. To reduce cost of group key agreement farther, a group key agreement protocol based on m-tree and DMDH assumption was developed. Key agreement was completed by which all group members agreed on variable m to fix on key tree and selected corresponding multilinear map from cluster of multilinear maps.Finally, in order to validate the practicality of the proposed, the general communication security layer is integrated into classic spread system seamlessly to implement efficient secure group communication. According to experimental results, this system makes a great progress in performance while meeting the demand of its security by comparing with existing systems.