An Approach to Analyze Covert Channel Based on Finite State Machine

Most researches in the field of covert channel concerned a specific channel, and few works resolved the general situations. This paper focuses on the system that can be modeled as a finite state machine, introduces an approachto modify the machine. Researcher can use the modified finite state machine to set up a noiseless covert channel in the system, calculate the covert channel´s information leakage, and get the necessary and sufficient condition for the system to be secure. To show the approach´s availability, this paper gives an example to show the whole process.