Traffic-flow security

Traffic analysis is the process of intercepting and examining messages in order to deduce information from patterns in communication. It can be performed even when the messages are encrypted and cannot be decrypted. In general, the greater the number of messages observed, or even intercepted and stored, the more can be inferred from the traffic. Traffic analysis can be performed in the context of military intelligence, counter-intelligence, or pattern-of-life analysis, and is a concern in computer security.

Traffic analysis tasks may be supported by dedicated computer software programs. Advanced traffic analysis techniques may include various forms of social network analysis.

In a military context, traffic analysis is a basic part of signals intelligence, and can be a source of information about the intentions and actions of the target. Representative patterns include:

There is a close relationship between traffic analysis and cryptanalysis (commonly called codebreaking). Callsigns and addresses are frequently encrypted, requiring assistance in identifying them. Traffic volume can often be a sign of an addressee's importance, giving hints to pending objectives or movements to cryptanalysts.

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:

Traffic-flow security is one aspect of communications security.

The Communications' Metadata Intelligence, or COMINT metadata is a term in communications intelligence (COMINT) referring to the concept of producing intelligence by analyzing only the technical metadata, hence, is a great practical example for traffic analysis in intelligence.

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