Mathematical Models of the Covert Channels

The analysis of the covert channels is necessary for construction of the protected computer systems, stenography, including methods of construction of labels for the intellectual property protection and secure labels of the copies of information objects. In some conditions it is possible to prove the invisibility by the supervising subject of the covert channel. The review of cases is given, when in some absolute sense using methods of the theory of probability and statistics it is possible to prove the "invisibility" of the covert channel by the supervising subject.