Multiple Operations for Secure Multicast Communication

Group key management is a critical task to make the secure multicast application. Group manager is responsible for changing and re-distributing (rekeying) the group key whenever it deems necessary. Many applications will require a security infrastructure that ensures multiple levels of access control for group members and also require very fast rekeying so that it is not disruptive to their performance. We use a multi-operation key management scheme that achieves hierarchical group access control. Particularly, we use an integrated key graph that maintains keying material for all members with different access privileges. It also incorporates new functionalities that are not present in conventional multicast key management, such as user relocation on the key graph. We use the ECC-GKM elliptic curve cryptosystem for the key exchange and we show the multiple operations such as joining, leaving and switching for multiple levels of access control.