Biometric authentication methods may also serve as a form of two-factor authentication (2FA) or multi-factor authentication (MFA), either by combining multiple biometric patterns or in conjunction with a traditional password or secondary device that supplements the biometric verification. Biometrics do still face some obstacles to widespread consumer adoption. Certain biometric technologies are very complicated to program, install, and use, and may require educating consumers to assure they are used correctly. Security updates are critical to ensure that biometric data and functions continue to work properly. Error rates are still a problem with some biometric measures as well, and frustration with errors may make consumers less likely to adopt biometrics into everyday usage patterns. Despite these risks, biometric authentication is increasingly gaining acceptance across a number of industries that rely on security, and are likely to continue becoming more common in consumer-grade devices and applications.
Fingerprint scanners, the digital version of old-fashioned ink and paper fingerprinting, rely on recording the unique patterns of swirls and ridges that make up an individual's fingerprints. Fingerprint scanners are one of the most common and accessible modes of biometric authentication, though consumer-grade versions, such as those found on smart phones, still have the potential for false positives. Newer versions of fingerprint scanning move beyond fingerprint ridges and below the skin to assess the vascular patterns in people's fingers, and may prove more reliable. Despite their occasional inaccuracy, fingerprint scanners are among the most popular and utilized biometric technologies for everyday consumers.
Facial recognition technology relies on matching dozens of different measurements from an approved face to the face of a user trying to gain access, creating what are called faceprints. Similar to fingerprint scanners, if a sufficient number of measurements from a user match the approved face, access is granted. Facial recognition has been added to a number of smart phones and other popular devices, though it can be inconsistent at comparing faces when viewed from different angles, or when trying to distinguish between people who look similar, such as close relatives.
Several types of eye scanners are commercially available, including retina scanners and iris recognition. Retina scanners work by projecting a bright light towards the eye that makes visible blood vessel patterns which can then be read by the scanner and compared to approved information saved in a database. Iris scanners operate similarly, this time looking for unique patterns in the colored ring around the pupil of the eye. Both types of eye scanners are useful as hands-free verification options, but can still suffer inaccuracies if subjects wear contact lenses or eye glasses. Photographs have also been used to trick eye scanners, though this method is likely to become less viable as scanners become more sophisticated and incorporate factors like eye movement into their verification schemes.