Tree-type secure multicast scheme based on digital certificate

A new scheme based on digital certificate is proposed to implement secure multicast. In the scheme, tree-type multicast topology (multicast tree) is adopted. Each node of the multicast tree possesses a digital certificate which may indicate its identity in the multicast group. Also the certificate may be used for distributing session-key and authenticating session data. So the complexity of managing multicast group key is reduced. And because of tree-type structure of the multicast group, the joining and leaving for multicast member is more scalable.