Certificate-based encryption (CBE) is a new<br>asymmetric encryption paradigm which combines<br>traditional public-key encryption (PKE) and identity based<br>encryption (IBE) while preserving some of their most<br>attractive features. CBE provides an efficient implicit<br>certificate mechanism to eliminate third-party queries for<br>the certificate status and to simply the certificate revocation<br>problem. Therefore, CBE can be used to construct an<br>efficient PKI requiring few
