A mandatory secure access control model named SOSACM of Operating System that is based on the multi-level security policy is put forward. Its confidetiality inherits the BLP model,and its definition of integrity is on the basis of Biba model.

• 提出了一个基于多级安全策略的强制访问控制模型；它的保密性安全规则是基于BLP模型；而完整性安全规则是基于Biba模型.