Passive Biometrics

Biometric technologies can be classified as physiological or behavioral, and further split into passive systems that require no active user participation and active systems that do.

While difficult to define in an all-encompassing manner, probably one of the best definitions of biometrics is:

The use of physiological or behavioral characteristics of a human being, through automated technological means, to determine or verify the identity of that person.

Physiological biometrics use algorithms and other methods to define identity based on data gathered from direct measurement of the human body. Fingerprint and finger scan, hand geometry, iris and retina scanning, and facial geometry are all examples of physiological biometrics.

Behavioral biometrics, however, are defined by analyzing a specific action of a person. How a person talks, signs their name, or types on a keyboard is a way of determining identity when analyzed correctly.

Biometrics can also be classified as either Passive or Active. Passive biometrics do not require a user's active participation and can succeed even without the person knowing that they have been analyzed. Active biometrics, by contrast, do require the person's cooperation and will not work if they refuse to participate in the process.

• All fingerprint technologies
• Hand geometry technologies
• Retina scanning technologies
• Signature recognition technologies

• Voice recognition technologies (limited)
• Iris recognition technologies (limited)
• Facial recognition (truly passive)