Abstract: The problems of existing authentication frameworks are analyzed,and a universal authentication protocol is proposed for the multi-domain.Moreover,entity authentication for cross-domain is supported in the protocol.Especially,by using the modular approach under the Canetti-Krawczyk model,the security of entity authentication is analyzed.It is shown that the proposed protocol is secure and could achieve the security requirements,and the protocol is a secure and fast authentication with high expansibility.This protocol can be applied to the authentication between the networks which use the difference authentication frameworks.