Abstract：Certificate managing is always the bottleneck of PKI, which is the main way to resolve information security problem, but ID-based crypto system constructed by bilinear pairing can solve well.Based on the study of some based-pairing cryptosystem, we can find them must resolve the following questions: (1) Decide whether Bilinear Diffie-Hellman Problem is realy a hard question or not; (2) Find more efficient arithmitric to compute bilinear pairing; (3) Propose more secure, efficient and special signature schemes, such as threshold signature and proxy signature etc.

Keyword：bilinear pairing;ID-based cryptography;Bilinear Diffie-Hellman Problem;