What are Keystroke Dynamics?

Keystroke dynamics, also known as typing dynamics, is the analysis of a person’s typing habits such as the amount of time a key is pressed or between keystrokes. Looking at these habits in depth can produce a pattern or profile unique to each individual. Keystroke dynamics is a form of biometrics and is being considered as a way to increase computer security; unlike a password, typing habits can’t easily be intercepted or stolen. It can be used in conjunction with traditional login systems or in a real-time monitoring mode.

Human beings have a number of traits that are unique to each individual, i.e., from the way someone walks to the way each person signs his or her name. As technology has advanced, these traits began leaving telltale patterns in new and unexpected places. Experienced telegraph operators, for example, could tell one another apart just by the one-of-a-kind style each operator had when keying in the dots and dashes of Morse code. Keystroke dynamics expands this principle to the era of modern technology, thus replacing the telegraph with a computer keyboard and the operator with a computer algorithm.

The simplest forms of keystroke dynamics are based on two simple metrics: the amount of time any one key is held down, i.e., dwell time, and the amount of time spent between releasing one key and pressing another, known as flight time. These two measures can be recorded using an ordinary keyboard in a practice known as keystroke logging. Once logged, this data can be used to construct a kind of digital signature unique to each user. Much like a handwritten signature, a digital signature varies only slightly each time a user types a given set of characters like a password. This means that a computer can apply algorithms to make a well-educated guess about whether or not a user is who he or she claims to be.

Keystroke dynamics has been seen by some security experts as an inexpensive and less intrusive form of biometric technology. Biometrics, the use of physical and behavioral traits to identify an individual, can heighten security but often requires new systems which can be both costly and intrusive. Keystroke dynamics requires no specialized hardware and can strengthen existing login systems; unlike a password, a user’s typing habits can’t easily be stolen or copied. Some industries, such as banking and healthcare, have begun to adopt this approach. For other fields that require constant attention from trained professionals such as air traffic control, keystroke dynamics can provide a continuous monitoring tool that can detect both distraction or impairment as well as unauthorized access.