Iris Biometrics

Iris biometrics offer the biggest "cool" factor of all the biometrics. Iris biometrics are most often seen in spy movies, and are associated with securing only the most important data. When it comes to its use as a biometric for network security, some shortcomings are evident, yet other characteristics of iris biometrics are very attractive. Its greatest strengths lay in the FRR and FAR, as seen in Figure 9-4. The greatest weakness comes from being highly invasive. What follows is a breakdown of each characteristic for iris biometrics.

Figure 9-4. Scores for iris biometrics.

Acceptance: 4

Even though iris biometrics have a high cool factor, users are less accepting of them. The main reason for this is the perceived invasive nature of the biometric. Users have a hard time coming to grips with a light being shined into their eyes. It is the fear of injury to the eye that increases their uneasiness.

Easy: 4

Since the biometric in use is actually internal to the body, the positioning and relative closeness of the user to the reader are very high. Also, the need to perfectly align the eye with the scanner is required, which can cause some dexterity issues for users.

ROI: 4.5

The cost of the hardware needed for iris biometrics is relatively high. The camera needs to have a specialized light source to properly illuminate the iris. This does not lend itself well to achieving economies of scale. Also, the level of dexterity required to use the camera and the relative reluctance of the users to use it produce a high-cost/low-savings environment.

Deployable: 6

The iris biometric for network security is very similar to the face biometric for deployment. Unlike a face biometric camera, an iris biometric camera is not as susceptible to ambient lighting conditions. It does require a fair amount of desktop real estate, and it needs to be mounted so that the user is very comfortable with its use. This can require the installer to spend time fine-tuning the camera position for each user.

Noninvasive: 1

Iris biometrics without question are the most invasive. The very nature of the biometric being used contributes to this fact. It should be noted that most of the insistence that iris biometrics are invasive is purely user perception. Perception can be changed over time with education and more widespread use. If the iris biometric is to make it big in network access, this is one area that will need to be overcome .

Mature: 6

Even though iris biometrics have been commercially available for only about a decade , they are relatively mature. The research behind the use of the iris, and the simplicity and strength of the algorithm, lead to a relatively high maturity score. Where the iris biometric needs additional maturity is in the areas of user acceptance and hardware cost reduction.

FAR: 9

The FAR of the iris biometric is second to none. It is very robust and reliable. In the tens of millions of comparisons done in testing, not one false acceptance was seen. No biometric will ever match the ideal criteria. Since the FAR is a measure of probability, and it is used in conjunction with the law of large numbers , there is bound to eventually be a false acceptance.

FRR: 7.5

For the very reasons that give iris biometrics an incredible FAR, the same holds true for the FRR. The majority of the FRR is normally caused by user error in placement of the iris for recognition. This difficulty in placement is what drives down the score of the iris biometric. These failures can also be called failures to acquire . If a failure to acquire occurs during verification, it can then cause the user to be falsely rejected.

Size : 6

The size of the camera needed for iris biometrics is relatively large. Like face biometrics, the camera requires a fair amount of desktop real estate for deployment.

Habituation: 5

The use of iris biometrics can require the user to be highly habituated. The user needs to present the iris to the camera in just the right way. This can be difficult to do, as the user may have a hard time holding his/her head still, or may have a slight fear of light being shined into the eye. This could cause a person to not be as confident in their placement as he/she should be.