Showing posts with label Biometrics. Show all posts
Showing posts with label Biometrics. Show all posts

Sunday, January 9, 2011

What is the difference between "biometric identification" and "biometric verification"?

What is the difference between "biometric identification" and "biometric verification"?

Biometrics are used for different purposes, but they are generally part of either a verification system or an identification system. The differences between these two types of systems can make a difference in how quickly the system operates and how accurate it is as the size of a biometric database increases.

Verification Systems
Verification systems seek to answer the question “Is this person who they say they are?” Under a verification system, an individual presents himself or herself as a specific person. The system checks his or her biometric against a biometric profile that already exists in the database linked to that person’s file in order to find a match.

Verification systems are generally described as a 1-to-1 matching system because the system tries to match the biometric presented by the individual against a specific biometric already on file.
Because verification systems only need to compare the presented biometric to a biometric reference stored in the system, they can generate results more quickly and are more accurate than identification systems, even when the size of the database increases.

Identification Systems
Identification systems are different from verification systems because an identification system seeks to identify an unknown person, or unknown biometric. The system tries to answer the questions “Who is this person?” or “Who generated this biometric?” and must check the biometric presented against all others already in the database. Identification systems are described as a 1-to-n matching system, where n is the total number of biometrics in the database. Forensic databases, where a government tries to identify a latent print or DNA discarded at a crime scene, often operate as identification systems.



one-to-one comparison, biometric verification systems are generally much faster than biometric identification systems. Most commercial applications of biometrics for time and attendance or access control use biometric verification.

Tuesday, June 1, 2010

Fingerprint Verification

What is the fingerprint verification technology?

A fingerprint in its narrow sense is an impression left by the friction ridges of a human finger. In a wider use of the term, fingerprints are the traces of an impression from the friction ridges of any part of a human or other primate hand. 

Since the early 20th century, fingerprint detection and analysis has been one of the most common and important forms of crime scene forensic investigation. More crimes have been solved with fingerprint evidence than for any other reason. This fact necessitated the need for assailants to cover their hands during the commission of their crimes; thus designating gloves to be the most essential and crucial tool for any successful criminal perpetrator.
Fingerprint verification method?
There are two types of method, optical and capacitance. 

Optical fingerprint imaging involves capturing a digital image of the print using visible light. This type of sensor is, in essence, a specialized digital camera. The top layer of the sensor, where the finger is placed, is known as the touch surface. Beneath this layer is a light-emitting phosphor layer which illuminates the surface of the finger. The light reflected from the finger passes through the phosphor layer to an array of solid state pixels (a charge-coupled device) which captures a visual image of the fingerprint. A scratched or dirty touch surface can cause a bad image of the fingerprint. A disadvantage of this type of sensor is the fact that the imaging capabilities are affected by the quality of skin on the finger. For instance, a dirty or marked finger is difficult to image properly. Also, it is possible for an individual to erode the outer layer of skin on the fingertips to the point where the fingerprint is no longer visible. It can also be easily fooled by an image of a fingerprint if not coupled with a "live finger" detector. 

Capacitance sensors use principles associated with capacitance in order to form fingerprint images. In this method of imaging, the sensor array pixels each act as one plate of a parallel-plate capacitor, the dermal layer (which is electrically conductive) acts as the other plate, and the non-conductive epidermal layer acts as a dielectric

Coverage
It is widely used in access control, building management, bank, airport information system, etc