BIOMETRIC SYSTEM PERFORMANCE

Performance of a biometric system is usually expressed by some parameters. A decision made by a biometric system is either a “genuine individual” type of decision or an “impostor” type of decision. For each type of decision, there are two possible outcomes, true or false. Therefore, there are a total of four possible outcomes: a genuine individual is accepted or a genuine match occurred, a genuine individual is rejected or a false rejection occurred, an impostor is rejected or a genuine rejection occurred and an impostor is accepted or a false match occurred. As with any process, the correctness of the procedure can be estimated in a formalized manner through special parameters, namely two error rates—false accept rate and false reject rate, often referred to as false acceptance rate....

Due to the recent security threats originating from variety of sources (international terrorism, organized crime, commercial espionage, illegal immigration, cyber security, etc.), the use of biometric systems for person authentication has increased considerably as seen in variety of application scenarios including forensic, civil, and commercial sector, government sector, genetics, and health care.

The use of biometric in law enforcement and forensic is known for at least a few hundred years. Fingerprint identification system is one of the original and the most widely used biometric system for this purpose. Such system is used not only to link suspects to crime scenes, but also to link persons arrested under another name to other potentially relevant cases, to identify victims of the crime and to associate persons with events in complex databases. Other biometric identifiers which are used in forensic sector include face, signature, gait, voice and DNA. Face and gait can be used for surveillance purposes very busy places such as stadiums, airports, meetings, etc. Signature and voice van be used for identification of criminals. Recently, DNA matching is used more and more to identify criminals due to a higher accessibility of such technology and its lowering costs.