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Keystroke dynamics is a relatively new field that enables identification of individuals through statistical analysis of their typing patterns. Previously published articles on developerWorks have shown how to integrate the concept of keystroke dynamics into your applications, as well as a real-world example of modifying Gnome Display Manager (GDM) to require a correct password and a "correctly typed" password. This article presents tools and code allowing you to move beyond a single application of keystroke dynamics, and monitor your entire X Window System environment continuously for characteristic patterns of the typist.

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