Biometrics Week 2 Flashcards
What is authentication?
Is the process of verifying or determining the user’s identity.
A natural recognition capability for human being.
Automated authentication assign the task of authentication to machine for greater security, efficiency, and convenience.
Authentication can be?
Verification: Am I who I claim I am?
Or
Identification: who am I? (for finding a “wolves in a sheep clothes”)
Authentication can be Based on Different Concepts:
Knowledge
Possession
Biometrics
Any combination of the three
Knowledge Based Authentication
Something you know:
a password, pass-phrase, PIN…
Works reliably if they are not easily guesses, disclosed…
Problem with Knowledge based Approach
Problem:
difficult to remember,
easily guessed by imposters
Can be stolen or forgotten
Can be shared: a limited degree of accountability with transferability of credentials.
More than 15% of people seem to write their PIN on their ATM card
Possession Based Authentication
Something you have:
identity document, a token, a key, a card,..
Solve some of the problems with knowledge-based authentication forms:
No need to remember password
A limited degree of accountability with transferability of credentials.
The owner can tell if the card or token is stolen
Problem with possession-based approach
Possession could be:
lost,
stolen
shared
misplaced
forgotten
Benefits of Biometrics
Convenient: nothing to lose or remember
Can’t be guessed, stolen, shared or lost
Non-repudiation: Links an access to a person, not to a password or a card.
Protects against identity theft
Higher perceived degree of security
Security Levels combos:
Know Have Are
Have Are
Know Have
Know
Major Factors Influencing the Adoption of Biometrics
Security
Higher security through non-repudiation
Can not be stolen/ easily reproduced/guessed
Convenience
Integral and distinctive part of human being
Set it up once and forget about it
Cost/Technology
Higher return on investment through higher protection
Drop in the price of biometric sensors
The underlying technology is becoming more mature
Products have attained higher level of accuracy and throughput
Why Convergence?
Streamlined Provisioning/de-Provisioning
Single Point of enrollment
Lowered risk of penetration
Ease of Use
Shared Credentials
Reduced Cost
Lowered risk of credential sharing
Common Security Policies
Improved Accountability
Better Audit capability
Policies commensurate with overall corporate objectives
Compliance with Regulatory Processes
Biometrics Based Authentication
Biometrics = bio (life) + metrics (to measure)
Deals with automated methods of verifying or recognizing living persons based on their:
Biological characteristics (e.g., face, fingerprint, iris, hand geometry, retina)
Behavioral characteristic (e.g., signature, gait)
Combined (e.g., Voice)
No human involved in the authentication process
Should be done in real-time
Criteria for a Biometric Solution to be Applied for Authentication
Universality or Availability
Every person should have the characteristic
Uniqueness or Distinctiveness
Different persons should have different characteristics
Also referred to as having the discriminatory power
Permanence or Robustness
The characteristic should be time invariant
Should not change with varying operating condition
Collectable or Accessibility
The characteristic should be measurable quantitatively within reasonable time frame
Performance
It should be practical to collect and measure, and it should give an acceptable identification rate.
Acceptability
Users should not have an objection to collect/measure
Circumvention
Should not be too easy to fool
Applications of Biometrics Systems
Forensics
Government
Commercial
Taxonomy of uses of Biometrics Systems
Positive identification
Verifies that the submitted sample is from an individual known to the system
exp. Access to a budlings, access to a mobile device,..
Negative identification
Exp. Verifies that the submitted sample is from an individual not known to the system
Exp. Uses for preventing duplicate in welfare.
Basic Functions of a Biometric System
Capture
The process of measuring the biometric characteristics of a person using a sensing device
Process
The process of converting the biometric feature into a numeric format (template) that can be stored into the database
Enrolment
Registering a biometric template of a person in a database
Identification
Finding the template in a database that matches the live template at hand.
Verification
One-to-one process: matching a live template against a single stored template
Voice
Different from speech recognition
Based on the analysis of voice patterns and characteristics such as pitch, tone,..
Voice signal is transformed and digitized
Speaker verification can be:
Text-dependent, text-independent, language independent, language dependent
Can be used for authentication over phone
Weaknesses
Background noise (airplanes)
Voice can be affected by the person’s health, emotion, …
It can be mimicked, recorded and re-played.
Lengthy enrollment
Attacks:
Tape recordings
Identical twins or people with sound-alike
Facial Recognition
A very natural process to human being
Analyze the unique shape, pattern, and position of facial features
Can be based on still or video images
Face biometrics can be applied covertly, and without person’s cooperation
2D Facial Recognition
A template can be created from a standard webcam
There is no contact with a sensor
Can be done from a far distance
Highly affected by lighting, position, eyeglasses, facial expressions
Relies heavily on controlled environment resulting in a high failure rate
Technologies for face recognition
Eigen face approach: Face appearance
Feature geometry: feature-based method
Neural network
3D Facial Recognition
Uses real-time capture of three-dimensional images of a subject’s face
The uniqueness of the person’s cranio-structure (skull curvature,..) is extracted and stored as a biometric template
Not affected by lighting, background colors, facial hair or makeup,
Uses structured light in near-infrared range where a projector shoots an invisible structured light pattern onto the face, and a video camera records the pattern distorted by the face’s surface geometry
A 3D mesh of the face is created by means of triangulation
Iris Recognition
Measures the features associated with the random texture of the colored part of the eye
Based in visible features i.e.
rings, furrows, freckles, and the corona
Requires cooperation from the user
Weakness:
fear and discomfort, proprietary acquisition devices.
Highly accurate
Very stable over-lifetime
It works perfectly even with glasses and contacts
It can be affected though by some diseases such as cataracts.
Iriscode
Uses near infrared sensors at a distance of 6 inch to 2 ft
You can measure up to 255 unique features. Features and their locations are used to form the iriscode, which is the digital template
Iris picture can be captured using a normal CCD camera with a resolution of 512 dpi or higher
Different Iriscodes care compared using Exclusive OR
Retina Scan
Based on the vascular structure at the back of the eye:
The pattern of blood vessels that emanate from the optic nerve and disperse throughout the retina depends on individuals and never change
An infrared light source is shone through the eye’s pupil to luminate the retina
Extremely accurate and secure
No two retinas are the same even for identical twins
It is considered intrusive, it can reveal some medical conditions, such as hypertension
Requires the user to remove eyeglasses
Long capture time, with 5-15 sec.
Most Significant Test Measures of Biometrics Systems
False Matching Rate (FMR)
False Non-Match Rate (FNMR)
Failure to Enroll (FTE)
Equal-Error-Rate (EER)