A novel abstract model for the design of trusted computing platform system was proposed.By using the basic idea of non-interference theory as reference and introduces the reasoning method of process algebra

thus abstracting the system as processes

actions

states and outputs

and giving the formal definition of the trusted of process running.Process isolation trusted theorem was verified formally.Furthermore

by associating process with system state

the definition and the theorem of system running trusted was proposed.The model was established by logic reasoning and independent of special security mechanism and enforcement.The trust of the running system can be realized by any method which satisfies the conditions of the model.