Traffic Flow Security [National Security] Law and Legal Definition

Traffic-flow security is a characteristic of communications security. It is the use of measures that hide the presence and properties of valid messages on a network to preclude traffic analysis. It prevents an interceptor from identifying what portions of the random text constitutes the encrypted message text and what portions are merely random filler. It is generally attained by means the features that are inherent in the crypto equipment that conceal the presence of valid messages on a communications circuit, by causing the circuit to appear busy continuously.

In general, some of the methods that are used for traffic-flow security are encrypting the sending and receiving addresses, causing a circuit to appear to be busy at all times by sending dummy traffic, and transmitting a continuous encrypted signal, irrespective of whether or not traffic is being sent.