Abstract: In this paper, online certificate status protocol （OCSP） is depicted and status authority （SA） is put forward for the first time. According to the HTTP-based model that is OCSP defined, a TCP-based model which can be combined with any other application is derived and its common interfaces are defined and added to the national standard draft about security middleware. Finally, in order to solve those problems about SA thruput, a "push" SA architecture based on message-oriented middleware is designed, and a testing data diagram of SA fetching in a real environment is given and its cost discussed.