Efficient revocable identity‐based encryption from multilinear maps
Xianping Mao, Junzuo Lai, Kefei Chen, Jian Weng, Qixiang Mei · Security and Communication Networks · 2015
Abstract In Identity‐Based Encryption (IBE) systems, there is a widespread concern over the issue on how to provide an efficient revocation mechanism. We develop a new approach in constructing an efficient revocable IBE scheme. Our approach utilizes recent advances in multilinear maps and combines a two‐level hierarchical IBE scheme with a revocation encryption system. In our revocable IBE scheme, both the public parameters and the private key are constant‐size. Simultaneously, the size of the update key at some time is only proportional to the number of revoked users at the time. Our proposed scheme is proven secure in the selective revocation list model without relying on random oracles. Copyright © 2015 John Wiley & Sons, Ltd.