Rekeying and Storage Cost for Multiple User Revocation

摘要

In this paper, we focus on tradeoffs between storage cost and rekeying cost for secure multi-cast. Specifically, we present a family of algorithms that provide a tradeoff between the number of keys maintained by users and the time required for rekeying due to revocation of multiple users. We show that some well-known algorithms in the literature are members of this family. We show that algorithms in this family can be used to reduce the cost of rekeying by 43%-79% when compared with previous solutions while keeping the number of keys manageable. We also describe a scheme that allows one to reduce the number of keys further without increasing the rekeying cost.