Re-keying scheme for secure multicast based on multi-group key tree

A re-keying scheme with multi-group key tree shared between multicast groups under group members (GMs) overlapping condition was presented in this paper, and solved the problem that re-keying cost of multicast groups had a linear relationship with the number of multicast groups. In this scheme, leaf nodes on tree were private keys of GMs, extended root nodes were group keys and keys corresponding to all nodes were updated using Pseudo. Random Function (PRF) and Exclusive OR (XOR) operation. The simulation results of verification system show that this scheme obviously improves re-keying performance to some extent under communication scene with multicast groups.