This work aims to present the main characteristics of the biometric technology related to iris gratitude used currently in the control of physical access, therefore the biometry is known as the measurement technique more assurance currently in the identification of a person. Iris localization is one of the most essential steps in iris gratitude system and determines the accuracy of harmonizing. In this, efficient techniques for iris  localization are proposed and explain how iris is providing high security in restricted & unrestricted sectors. Biometrics itself a science of establishing human distinctiveness by using corporeal or behavioral persona such as face, fingerprints, palm prints, iris, hand geometry, and voice. The control of the physical entrance in computerized safekeeping systems, like banks, ports, airports and military areas, is vital to pledge the economical security of the institutions and to thwart to the possibility of accomplishment of uncompromising acts. To this, a lot of technologies used in security systems can be used, but the choice of a technology depends on some factors, as the level of security related with the economical value to be sheltered, the entailed cost to the technology carrying out related to the level of security presented, and the physical characteristics to the proper installation.