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Q: More biometric access control products than ever seem to be coming to market. What should installers and integrators look for as far as technical specifications or standards accompanying these particular devices?
A: Selecting the appropriate biometric access control technology depends on a number of application-specific factors, including the environment in which the identity verification process is carried out, the user profile, accuracy requirements and overall system cost.
User acceptance of the access control device is one of the most critical factors in the success of a biometric-based implementation. Part of this issue is common to the implementation of any security. However, some biometric technology adds an additional dimension of physical contact and/or interaction with a reader or terminal which some people could perceive as annoying.
Acceptance also is an issue for those who will be managing the system. Ease of enrolling users, reliability of the readers and the ease of template management are critical since the end-user is not necessarily your client. The end-user is probably a customer of your client.
Accuracy is vital to the acceptance of the biometric chosen. False positives, a.k.a. False Accept Rate (FAR), and false negatives, False Rejection Rate (FRR), occur as the biometric system inputs the biometric signature of the user and attempts to compare it to a template which is either stored in the terminal or resides in a network-connected database. These numbers represent a statistical probability that one of these will occur, and the ratio is a parameter set by the designer of the algorithm. FAR ranges from .0001 to 0.1 percent. FRRs vary from .00066 to 1.0 percent.
Setting the system to produce a very low rate of false acceptance usually causes a higher rate of false rejects. The application determines the acceptable levels of false accepts and false rejects. Since it is virtually impossible to individually verify these stats, it is best to stick to reliable known manufacturers who adhere to recognized industry standards.
Different types of biometric technologies on the market include:
Hand geometry—This biometric unit evaluates a three-dimensional image of the four fingers and part of the hand. It was the technology used for the very first commercially available biometric device, which came to market in 1976.
Fingerprint—Law enforcement agencies have used fingerprints for decades to identify individuals, but comparing the fingerprinting techniques employed by law enforcement with a biometric finger scanner may not be valid because the biometric scanner looks at only one finger and the number of sampling points on a fingerprint varies.
Face—The shape of the face, determined by distances between the eyes, ears and nose and other characteristics are put into a template. When scanned, the image is matched against the template to verify a person's identity. It has the advantages of not requiring individual contact with a terminal and it can be used to screen individuals within a group, perhaps gearing it up to be considered a valuable anti-terrorism tool.
Iris—Eye scanners typically store 247 traits of a person's iris into a template. Proponents believe the technique is more specific than fingerprinting.
Another emerging biometric technique incorporates a finger-scanner onto an access credential. The credential becomes enabled when the authorized individual holds the credential and presents it to the card reader.
The Security Industry Association offers a newsletter on smart cards and biometrics which keeps readers up to date on the technology and emerging standards. Go to http://go.reachmail.biz/sia/default.asp.
Tim O'Leary is a 35-year veteran of the security industry. He has been a security consultant since 1986 and an independent security company owner/operator and product researcher.
author: By Tim O'Leary