The invention relates to a method for certificateless cross-domain
authentication in a credible
cloud computing environment and belongs to the technical field of
cloud computing safety. According to the method for certificateless cross-domain
authentication in the credible
cloud computing environment, the certificateless
public key cryptography technology is introduced into cross-domain
authentication, credible cross-domain authentication is achieved in the process of credible cloud computing, a certificateless
public key cryptosystem is applied, the problem of the
certificate maintenance expense of a traditional digital
certificate authentication system and the problem of private key trusteeship of a
public key cryptography system based on the identity are solved. According to the method for certificateless cross-domain authentication in the credible cloud computing environment, a user public key is generated based on the identity, a part of a private key of a user is generated by the user, and the other part of the private key of the user is generated by a center
authentication server. According to the method for certificateless cross-domain authentication in the credible cloud computing environment, a
certificate system is abandoned, the expense of the
authentication system is reduced, the private key of the user is protected at the same time,
bilinear pairing computation is applied to the certificateless
public key cryptosystem, it is proved that a safety
hypothesis based on
bilinear pairing computation is high in safety, the certificateless
public key cryptosystem is used for identity authentication and
session key negotiation, and therefore it is ensured that the
system is high in safety.