Your face and fingerprints do not always look the same and your blood pressure varies, so any biometric system must build in room for error.

This convenience can significantly reduce the cost of maintaining a biometric system.

The block diagram illustrates the two basic modes of a biometric system.

Following enrolment, a biometric system will analyse physical or behavioural traits, such as fingerprints, iris, face, voice and hand geometry, to verify the identity of a beneficiary.

Unlike some biometric systems, blood vessel patterns are almost impossible to counterfeit because they are located beneath the skin's surface.