BIOMETRICS

By Nirmal -
Over the last few years a new area of engineering science has been established whose products are likely to create a large market in the near future. It has been called ''biometrics". The pioneers of this new domain intend to construct devices which would allow identification of a person on the basis of his/her ''biological'' characteristics: voice, dynamics of movements, features of face and other parts of the body, retina or iris pattern. Nature has made human beings with different characteristics which may vary from one person to another. This property is made use of by Biometric technology to distinctly identify each person
Biometric system is essentially a pattern recognition system which recognizes a user by determining the authenticity of a specific physiological or behavioral characteristic possessed by the user. Several important issues must be considered in designing a practical biometric system. First, a user must be enrolled in the system so that his biometric template can be captured. This template is securely stored in a central database or a smart card issued to the user. The template is retrieved when an individual needs to be identified. Depending on the context, a biometric system can operate either in a verification (authentication) or an identification mode.
Biometrics refers to the automatic identification of a person based on his/her physiological or behavioral characteristics. This method of identification offers several advantages over traditional methods involving ID cards (tokens) or PIN numbers (passwords) for various reasons: (i) the person to be identified is required to be physically present at the point-of-identification; (ii) identification based on biometric techniques obviates the need to remember a password or carry a token. With the increased integration of computers and Internet into our everyday lives, it is necessary to protect sensitive and personal data. By replacing PINs (or using biometrics in addition to PINs), biometric techniques can potentially prevent unauthorized access to ATMs, cellular phones, laptops, and computer networks. Unlike biometric traits, PINs or passwords may be forgotten, and tokens like passports and driver's licenses may be forged, stolen, or lost.
This paper gives an overview of key biometric technologies and basic technique involved. The various opportunities for biometrics are mentioned, followed by the uses, benefits, drawbacks, and applications.

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