INTRODUCTION

Authentication systems such as PIN, passwords utilize something you know. Physical entities such as key, token, card utilize what you have. Biometrics systems use what you are (your intrinsic physical features) - fingerprint, iris pattern or what you can do (your behavioral traits) - voice, gait etc. The biometric system eliminates the deficiencies of password system, such as use of easily compromised passwords, difficulty in remembering the password.

There are many different types of biometrics - handwriting, voice prints, face recognition and finger prints. There are also systems using hand geometry, typing patterns, iris scans, signature geometry (not just the look of the signature, but the pen pressure, signature speed) and so on. there are other biometric methods which may not particularly suit mobile applications: e.g. keystroke dynamics, gait, retinal, vascular pattern etc. The most widely used biometric authentications today are fingerprint, iris, signature, face and hand geometry.

As mobile phone use involves transfer of personal data through the Internet, financial transactions etc, the technology selected should be stringent on false accept rate, which means that chances of permitting access to an imposter will be the least, even at the cost of denying access to an authentic user. If biometric is part of a two-part authentication system. such as fingerprint verification and password, then a lower false accept rate with high false reject rate will be in order. However, biometric systems have improved over the years to be more accurate in terms of achieving low false accept rates as well as low false reject rates.
Biometric authentication requires two stage operations: Enrollment and authentication (one-to-one comparison of user's input and template) or identification (one-to-many comparison of user's input with a data base of templates). The former is important for mobile applications. Also the important feature to consider is Accuracy or threshold value. A block diagram showing the steps involved in biometric system is given above.

Privacy relate to the apprehension of the individuals that data obtained during biometric enrollments could be used in ways the enrolled individual does not consent to. Governmental and nongovernmental regulations and guidelines in some countries do attempt to provide some safeguards. For example the Irish Council of Bioethics (ICB) in its report has advised that biometric technology, though powerful must be used appropriately to avoid resentment and paranoia among users. The European Bio Sec consortium is working to develop a legal framework for the use of biometric technologies that ensures full compliance with European regulations in the area of data protection.



Reference:

http://pagesperso-orange.fr/fingerchip/biometrics/types.htm
http://en.wikipedia.org/wiki/Biometric
http://www.techcentral.ie/article.aspx?id=14260
http://www.it-director.com/technology/security/content.php?cid=7735