Biometric Authentication compares the current biometric data capture to stored, confirmed authentic data in a database.
Biometric Authentication is based on the ways in which individuals can be uniquely identified through one or more distinguishing biological traits, such as fingerprints, hand geometry, earlobe geometry, retina and iris patterns, voice waves, keystroke dynamics, DNA and signatures.
Biometric Authentication is possible for existing customers or users whose identity has already been authenticated and matched to their biometric traits.
Biometric Authentication cannot be used to identify people for whom there is no prior data.
Ref.: http://searchsecurity.techtarget.com/definition/biometric-authentication