Editing Traffic analysis (section)

===Traffic flow security===
'''Traffic-flow security''' is the use of measures that conceal the presence and properties of valid messages on a network to prevent traffic analysis. This can be done by operational procedures or by the protection resulting from features inherent in some cryptographic equipment. Techniques used include:

* changing radio [[callsign]]s frequently
* encryption of a message's sending and receiving addresses ('''codress messages''')
* causing the circuit to appear busy at all times or much of the time by sending dummy [[traffic]]
* sending a continuous encrypted [[signal]], whether or not traffic is being transmitted. This is also called '''masking''' or  '''link encryption'''.

Traffic-flow security is one aspect of [[communications security]].