Biometric Authentication Definition

KZero Staff
Jul 27, 2023

What is Biometric Authentication?

Authentication is the process of proving a user’s identity to a system before granting them access. Authentication can be performed in several different ways, typically by requiring the user to demonstrate something unique to the legitimate user.

Biometric authentication systems use the person’s physical features or behaviors to authenticate them. This creates an authentication system that is more secure and user-friendly than many alternatives.

What are Authenticator Factors?

An authentication factor is something used to prove a person’s identity. In general, most authentication systems use factors that fall into one of three categories:

  • Something You Know: This type of authentication factor requires the user to demonstrate some unique, secret knowledge. Common examples include passwords, PINs, and security questions.
  • Something You Have: This form of authentication identifies a user based on their possession of a physical authentication factor. For example, the system may request a one-time password (OTP) or a digital signature generated or received by a smartphone, smart card, or hardware authentication token.
  • Something You Are: Biometric authentication factors measure something inherent to the person performing the authentication. This could include fingerprints, their voice, or how they walk.

How Does Biometric Authentication Work?

Biometric authentication uses unique features of an individual to verify their identity. When the user creates an account, the system collects biometric information from them and adds it to their profile to use while verifying their identity in the future.

The exact mechanism of verifying a user’s identity depends on the type of biometric authentication used. For example, fingerprint recognition is based on measuring a set of points on the user’s fingerprint. If a provided fingerprint matches the information stored in the user’s record, then they are authenticated and granted access.

Other systems may require machine learning (ML) to perform the authentication process. For example, voice recognition systems are trained on the user’s voice and build a model for recognizing them. When the user speaks again, these systems can still identify them despite variations in their voice due to stress, a cold, the environment, and other factors.

Types of Biometric Authentication

In general biometric authentication refers to identifying and authenticating an individual based on their unique features. However, there are a couple of major classes of features that can be used:

  • Physical Biometrics: Physical biometric authentication identifies users based on their unique physical features. Fingerprint, voice, and facial recognition are all examples of physical biometric authentication systems.
  • Behavioral Biometrics: Behavioral biometric authentication systems authenticate users based on the unique ways in which they act. For example, users can be identified based on the way they walk, interact with a smartphone, or type on a keyboard.

Advantages of Biometric Authentication

Biometric authentication systems provide significant benefits when compared with other options. Some of the biggest benefits include:

  • Security: Biometric authentication systems offer better security than most other options. For example, they eliminate the risk of weak passwords or phishing attacks which are a major concern with password-based authentication.
  • Convenience: Biometric authentication measures the unique attributes of a person. This eliminates the need to carry around a smartphone or other physical authentication token or to remember knowledge-based factors.
  • User Experience: Biometric authentication is typically more frictionless and easy than other forms of authentication. For example, tapping a finger on a scanner is far easier than remembering and entering a long, complex, and unique password.


Biometrics offers a secure, user-friendly option for authentication. They are growing increasingly popular as a secondary authentication factor for multi-factor authentication (MFA) schemes. They also play a key role in passwordless authentication, which attempts to eliminate knowledge-based authentication factors like passwords entirely.

KZero Staff

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