IRIS SCAN

INTRODUCTION

In today’s information age it is not difficult to collect data about an individual and use that information to exercise control over the individual. Individuals generally do not want others to have personal information about them unless they decide to reveal it. With the rapid development of technology, it is more difficult to maintain the levels of privacy citizens knew in the past. In this context, data security has become an inevitable feature. Conventional methods of identification based on possession of ID cards or exclusive knowledge like social security number or a password are not altogether reliable. ID cards can be almost lost, forged or misplaced: passwords can be forgotten. Biometric technology has now become a viable alternative to traditional identification systems because of its tremendous accuracy and speed. This paper explores the concept of Iris recognition which is one of the most popular biometric techniques. This technology finds applications in diverse fields.

BIOMETRICS - FUTURE OF IDENTITY

Biometric dates back to ancient Egyptians who measured people to identify them. Biometric devices have three primary components.

1. Automated mechanism that scans and captures a digital or analog image of a living personal characteristic

2. Compression, processing, storage and comparison of image with a stored data.

3. Interfaces with application systems.

A biometric system can be divided into two stages: the enrolment module and the identification module. The enrolment module is responsible for training the system to identity a given person. During an enrolment stage, a biometric sensor scans the person’s physiognomy to create a digital representation. A feature extractor processes the representation to generate a more compact and expressive representation called a template. For an iris image these include the various visible characteristics of the iris such as contraction, Furrows, pits, rings etc. The template for each user is stored in a biometric system database. The identification module is responsible for recognizing the person. During the identification stage, the biometric sensor captures the characteristics of the person to be identified and converts it into the same digital format as the template. The resulting template is fed to the feature matcher, which compares it against the stored template to determine whether the two templates match.

The identification can be in the form of verification, authenticating a claimed identity or recognition, determining the identity of a person from a database of known persons. In a verification system, when the captured characteristic and the stored template of the claimed identity are the same, the system concludes that the claimed identity is correct. In a recognition system, when the captured characteristic and one of the stored templates are the same, the system identifies the person with matching template.

TOPOLOGY OF IDENTIFICATION METHODS

Biometrics encompasses both physiological and behavioral characteristics. A physiological characteristic is a relatively stable physical feature such as finger print, iris pattern, retina pattern or a Facial feature. A behavioral trait in identification is a person’s signature, keyboard typing pattern or a speech pattern. The degree of interpersonal variation is smaller in a physical characteristic than in a behavioral one. For example, the person’s iris pattern is same always but the signature is influenced by physiological characteristics.

DISADVANTAGES

Even though conventional methods of identification are indeed inadequate, the biometric technology is not as pervasive and wide spread as many of us expect it to be. One of the primary reasons is performance. Issues affecting performance include accuracy, cost, integrity etc.

Accuracy:

Even if a legitimate biometric characteristic is presented to a biometric system, correct authentication cannot be guaranteed. This could be because of sensor noise, limitations of processing methods, and the variability in both biometric characteristic as well as its presentation.

Cost:

Cost is tied to accuracy; many applications like logging on to a pc are sensitive to additional cost of including biometric technology.

ACCURACY

The figure illustrates a comparison between coast and accuracy. The cost represented here is a typical incremental investment needed for accruing a commercially available biometric sensor and for implementing and identity authentication system.

The biometric system has the disadvantages of being intrusive both physically and socially. They require the users to position their bodies relative to the sensor and then pause for a second.