Certificate Revocation Using Fine Grained Certificate Space Partitioning

A new certificate revocation system is presented. The basic idea is to divide the certificate space into several partitions, the number of partitions being dependent on the PKI environment. Each partition contains the status of a set of certificates. A partition may either expire or be renewed at the end of a time slot. This is done efficiently using hash chains. We evaluate the performance of our scheme following the framework and numbers used in previous papers. We show that for many practical values of the system parameters, our scheme is more efficient than the three well known certificate revocation techniques: CRL, CRS and CRT. Our scheme aims to strike the right balance between CA to directory communication costs and query costs by carefully selecting the number of partitions.