An Batch Renew Algorithm of Minimum Key Updating for Secure Group Communication
Shouzhi Xu · Journal of Chinese Computer Systems · 2007
Secure group communication always adopts K-ray logical tree based scheme. Its scalability is enslaved to costs of time and multicast bandwidth, which are restrained by the number of middle nodes updated, multicast packets and encryptions, where the first one is the key factor. Since these are related to the group size, number of changes and their distribution, all existing works doesn't meet the commands of applications with large group size and high dynamic members. In this paper, Minimum Exact Cover Problem (MECP) for key distribution is presented, and a heuristic solution is testified. Based on it, an algorithm named GMEC of batch rekeying with renewing cost tending to zero is illustrated, which can process any large number of change requests with best secrecy guaranteed. The result shows that the algorithm can improve efficiency more.