by: Murali

ABSTRACT

Biometric identification refers to identifying an individual based on his/her distinguishing physiological and/or behavioural characteristics. As these characteristics are distinctive to each and every person, biometric identification is more reliable and capable than the traditional token based and knowledge based technologies differentiating between an authorized and a fraudulent person. This paper discusses the mainstream biometric technologies and the advantages and disadvantages of biometric technologies, their security issues and finally their applications in day today life.

INTRODUCTION:

"Biometrics" are automated methods of recognizing an individual based on their physical or behavioral characteristics. Some common commercial examples are fingerprint, face, iris, hand geometry, voice and dynamic signature. These, as well as many others, are in various stages of development and/or deployment. The type of biometric that is "best " will vary significantly from one application to another. These methods of identification are preferred over traditional methods involving passwords and PIN numbers 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. Biometric recognition can be used in identification mode, where the biometric system identifies a person from the entire enrolled population by searching a database for a match.

A BIOMETRIC SYSTEM:

All biometric systems consist of three basic elements:

• Enrollment, or the process of collecting biometric samples from an individual, known as the enrollee, and the subsequent generation of his template.

• Templates, or the data representing the enrollee's biometric.

• Matching, or the process of comparing a live biometric sample against one or many templates in the system's database.

Enrollment

Enrollment is the crucial first stage for biometric authentication because enrollment generates a template that will be used for all subsequent matching. Typically, the device takes three samples of the same biometric and averages them to produce an enrollment template. Enrollment is complicated by the dependence of the performance of many biometric systems on the users' familiarity with the biometric device because enrollment is usually the first time the user is exposed to the device. Environmental conditions also affect enrollment. Enrollment should take place under conditions similar to those expected during the routine matching process. For example, if voice verification is used in an environment where there is background noise, the system's ability to match voices to enrolled templates depends on capturing these templates in the same environment. In addition to user and environmental issues, biometrics themselves change over time. Many biometric systems account for these changes by continuously averaging. Templates are averaged and updated each time the user attempts authentication.

Templates

As the data representing the enrollee's biometric, the biometric device creates templates. The device uses a proprietary algorithm to extract "features" appropriate to that biometric from the enrollee's samples. Templates are only a record of distinguishing features, sometimes called minutiae points, of a person's biometric characteristic or trait. For example, templates are not an image or record of the actual fingerprint or voice. In basic terms, templates are numerical representations of key points taken from a person's body. The template is usually small in terms of computer memory use, and this allows for quick processing, which is a hallmark of biometric authentication. The template must be stored somewhere so that subsequent templates, created when a user tries to access the system using a sensor, can be compared. Some biometric experts claim it is impossible to reverse-engineer, or recreate, a person's print or image from the biometric template.

Matching

Matching is the comparison of two templates, the template produced at the time of enrollment (or at previous sessions, if there is continuous updating) with the one produced "on the spot" as a user tries to gain access by providing a biometric via a sensor. There are three ways a match can fail:

• Failure to enroll.

• False match.

• False nonmatch.

Failure to enroll (or acquire) is the failure of the technology to extract distinguishing features appropriate to that technology. For example, a small percentage of the population fails to enroll in fingerprint-based biometric authentication systems. Two reasons account for this failure: the individual's fingerprints are not distinctive enough to be picked up by the system, or the distinguishing characteristics of the individual's fingerprints have been altered because of the individual's age or occupation, e.g., an elderly bricklayer. In addition, the possibility of a false match (FM) or a false nonmatch (FNM) exists. These two terms are frequently misnomered "false acceptance" and "false rejection," respectively, but these terms are application-dependent in meaning. FM and FNM are application-neutral terms to describe the matching process between a live sample and a biometric template. A false match occurs when a sample is incorrectly matched to a template in the database (i.e., an imposter is accepted). A false non-match occurs when a sample is incorrectly not matched to a truly matching template in the database (i.e., a legitimate match is denied). Rates for FM and FNM are calculated and used to make tradeoffs between security and convenience. For example, a heavy security emphasis errs on the side of denying legitimate matches and does not tolerate acceptance of imposters. A heavy emphasis on user convenience results in little tolerance for denying legitimate matches but will tolerate some acceptance of imposters.

BIOMETRIC TECHNOLOGIES:

The function of a biometric technologies authentication system is to facilitate controlled access to applications, networks, personal computers (PCs), and physical facilities. A biometric authentication system is essentially a method of establishing a person's identity by comparing the binary code of a uniquely specific biological or physical characteristic to the binary code of an electronically stored characteristic called a biometric. The defining factor for implementing a biometric authentication system is that it cannot fall prey to hackers; it can't be shared, lost, or guessed. Simply put, a biometric authentication system is an efficient way to replace the traditional password based authentication system. While there are many possible biometrics, at least eight mainstream biometric authentication technologies have been deployed or pilot-tested in applications in the public and private sectors and are grouped into two as given,

• Contact Biometric Technologies

  • fingerprint,

  • hand/finger geometry,

  • dynamic signature verification, and

  • keystroke dynamics

• Contactless Biometric Technologies

  • facial recognition,

  • voice recognition

  • iris scan,

  • retinal scan,

CONTACT BIOMETRIC TECHNOLOGIES:

For the purpose of this study, a biometric technology that requires an individual to make direct contact with an electronic device (scanner) will be referred to as a contact biometric. Given that the very nature of a contact biometric is that a person desiring access is required to make direct contact with an electronic device in order to attain logical or physical access. Because of the inherent need of a person to make direct contact, many people have co

audio equipment reviews

At Last - Useful Information on audio equipment reviews.

Listen On The Net Index