0 Heart Biometrics : Theory , Methods and Applications

Automatic and accurate identity validation is becoming increasingly critical in several aspects of our every day lives such as in financial transactions, access control, traveling, healthcare and other. Traditional strategies to automatic identity recognition include items such as PIN numbers, tokens, passwords and ID cards. Despite the wide deployment of such tactics, the authenticating means is either entity or knowledge-based which rises concerns with regard to their ease of acquisition and use from unauthorized third parties. According to the latest The US Federal Commission Report, Frebruary 2010 (n.d.), in 2009 identity theft was the number one complaint category ( a total of 721,418 cases of consumer complaints). As identity theft can take different forms, credit card fraud was the most prominent (17%), followed by falsification of government documents (16%), utilities fraud (15%), employment fraud (13%) and other. Among these cases, true-identity theft constitutes only a small portion of the complaints, while ID falsification appears to be the greatest threat. Unfortunately, the technology for forgery advances without analogous counterfeit improvements. Biometric recognition was introduced as a more secure means of identity establishment. Biometric features are characteristics of the human body that are unique for every individual and that can be used to establish his/her identity in a population. These characteristics can be either physiological or behavioral. For instance, the face, the iris and the fingerprints are physiological features of the body with identifying information. Examples of behavioral features include the keystroke dynamics, the gait and the voice. The fact that biometric features are directly linked with the users presents an extraordinary opportunity to bridge the security gaps caused by traditional recognition strategies. Biometric features are difficult to steal or counterfeit when compared to PIN numbers or passwords. In addition, the convenience by which a biometric feature can be presented makes the respective systems more accessible and easy to use. However, biometric recognition has a drawback that rises from the nature of the authenticating modality. As opposed to static PIN numbers or passwords, biometric recognition may present false rejection since usually no two readings of the same biometric feature are identical. Anatomical, psychological or even environmental factors affect the appearance of the biometric feature at a particular instance. For instance, faces may be presented to the recognizers under various expressions, different lighting settings or with 10