Identification versus Verification

In the biometrics industry, a distinction is made among the terms identification, recognition and verification.

Identification and recognition are, essentially synonymous terms. In both processes, a sample is presented to the biometric system during enrollment. The system then attempts to find out who the sample belongs to, by comparing the sample with a database of samples in the hope of finding a match (this is known as a one-to-many comparison).

Verification is a one-to-one comparison in which the biometric system attempts to verify an individual's identity. In this case, a new biometric sample is captured and compared with the previously stored template. If the two samples match, the biometric system confirms that the applicant is who he/she claims to be.

The same four-stage process — capture, extraction, comparison, and match/non-match — applies equally to identification, recognition and verification.

Identification and recognition involve matching a sample against a database of many, whereas verification involves matching a sample against a database of one.

The key distinction between these two approaches centers on the questions asked by the biometric system and how these fit within a given application.

During identification, the biometric system asks, "Who is this?" and establishes whether a biometric record exists, and, if so, the identity of the enrollee whose sample was matched.

During verification, the biometric system asks, "Is this person who he/she claims to be?" and attempts to verify the identity of someone who is using, say, a password or smart card.