sentences:  This model is applicable to a variety of critical infrastructure protection problems, where protection of the data in a network is less important than reliable control and correct operation of the network.For example, the public living downstream from a dam needs up-to-date information on the outflow, and the same information is a critical input to the control system for the floodgates.In such a situation, it is critical that the flow of information be from the secure control system to the public, and not vice versa.