A novel LKH key tree structure based on heuristic search algorithm

In multicast communication based on LKH, when a group member is added or evicted from the communication group, the system needs to update the group key to ensure the security of communication. In order to further reduce the rekey overhead, LKH is modified into a new key tree structure, which is constructed by heuristic search algorithm based on the number of group members. Compared to the LKH key tree structure, the branching factor of the new one can take on different value at each level. The experimental results showed the scheme proposed could efficiently reduce the encryption overhead, transmission overhead and the storage of keys during the rekey process.