Description: Type 3 authentication relies on a user’s physical characteristics (biometrics) or behavioral patterns. It is often considered the most secure form of authentication because it uses unique and inherent attributes of the individual that are difficult to replicate.

Key Characteristics:

• Biometrics: Uses physical characteristics to verify identity.
• Behavioral Biometrics: Uses patterns or behaviors, such as typing dynamics or voice patterns.
• Enrollment Time: Typically takes around 2 minutes per person for initial setup.
• Throughput Time: Acceptable processing speed is about 10 people per minute.

Common Metrics:

• Type 1 Error (False Rejection Rate – FRR): The rate at which legitimate users are incorrectly denied access.
• Type 2 Error (False Acceptance Rate – FAR): The rate at which unauthorized users are incorrectly granted access.
• Crossover Error Rate (CER or Equal Error Rate – EER): The point where FRR equals FAR. A lower CER indicates a more accurate biometric system.

Types of Biometrics:

1. Fingerprints:
   • Details: Based on ridge endings and bifurcations (minutiae).
   • Use: Stores full fingerprint for one-to-many identification or features for one-to-one identification.
   • Widely Used: Finger scan is the most widely used biometric today.
2. Retina Scans:
   • Details: Scans the blood vessel pattern in the retina at the back of the eyeball.
   • Accuracy: Most accurate biometric method but can reveal medical conditions.
3. Iris Scans:
   • Details: Scans the colored part of the eye surrounding the pupil.
   • Stability: Remains the same throughout a person’s life.
   • Considerations: Sensitive to lighting conditions.
4. Facial Scans:
   • Details: Analyzes bone structures, nose ridges, eye widths, forehead size, and chin shape.
5. Palm Scans:
   • Details: Scans the creases, ridges, and grooves of the palm.
   • Use: Can be used as a stand-alone Type 3 authenticator.
6. Hand Geometry:
   • Details: Measures the shape of the hand, including the length and width of the hand and fingers.
7. Voice Print:
   • Details: Analyzes the unique speech patterns and sounds.
   • Considerations: Can be affected by illness or background noise.
8. Signature Dynamics:
   • Details: Captures the speed and pressure dynamics of writing a signature.
9. Keyboard Dynamics:
   • Details: Analyzes the rhythm, pressure, and speed of typing patterns.
10. Hand Topology:
    • Details: Measures the size and shape of the hand and fingers.

Acceptability Issues:

• Privacy Concerns: Some users may feel uncomfortable sharing biometric data.
• Physical and Psychological Considerations: Concerns over physical discomfort or psychological resistance to biometric scanning.

Summary: Biometric authentication (Type 3) provides a high level of security by leveraging unique physical characteristics. It is widely used in environments requiring strong security, though it may face challenges related to user acceptance and privacy concerns.