Abstract: Based on an improved signcryption technique and the ID-based public key cryptosystem, a new authentication and key agreement protocol is proposed. The problem of passing and verifying the certificate needed in the traditional public key cryptosystem is well resolved. At the same time, the proposed protocol offers perfect forward secrecy. That is to say, even if the private key of the participant is exposed, the security of the negotiated keys does not suffer. Analysis shows that the proposed ID-based authentication and key agreement protocol is more secure and effective and more applicable than the others.

Key words: signcryption, ID-based public key cryptosystem, forward secret