Cipher - Electronic Newsletter of the Technical Committee on Security & Privacy.  A Technical Committee of the Computer Society of the IEEE.

Biometrics Identity Verification in a Networked World

September 13, 2002
Reviewed By Robert Bruen

Biometrics has become a major watchword since 9-11-02, but it has been around for quite a while. Recent advances have made the topic more interesting, especially with the new demands for public safety and security. The fear of terrorists hiding in a crowd pushes us to accept ideas that were once considered beyond the norms of a free, democratic society. The shining example is, of course, face recognition by cameras watching everyone who comes within sight. Faces are scanned and looked up in a database. There are a number of assumptions present as this takes place, such as the process works correctly. Other assumptions include that the databases only the images of bad guys in them and that the average citizen is not simply having their images stored in some database.

The use of biometrics goes back to fingerprints. They are a simple to capture with good reliability. The digital world has made access to large databases possible, companied by fast searches. These databases contain more than just criminal fingerprints since military personnel, security personnel, welfare recipients and others also have their fingerprints captured and stored. If the model for facial recognition is to be the same as the fingerprint model, then we can expect many more faces to be available in database. According to a recent Department of Defense report, facial recognition is not reliable enough to be put in the same category as fingerprinting. Logan Airport in Boston has been experimenting with facial recognition, but the results are not yet conclusive. It has not been shown to be that magic bullet we have been looking for.

When trying to understand why there is difficulty with facial recognition, one could read Nanavati's book. It is good introduction into the world of biometrics. It covers the existing biometric techniques without delving into the esoteric possibilities. The coverage is balanced, so that you get the strengths and weaknesses of the various techniques. For example, eye scans have several approaches, all of them suffering from the need to have the cooperation of the subject. One can scan the iris or the retina with good results in terms of individual recognition, but the scan must be close up to get the original image, as well as the comparative image. Most terrorists will not be so helpful. It will work in corporation in which all employees are required to undergo scans upon employment, then perhaps must submit to scans for entrance into restricted areas. This is helpful in understanding how this works.

In addition to the technology, Biometrics covers the business side of the house by listing various vendors, as well as explaining markets related to biometrics. it is not clear how well these companies will perform over time. There are competing forces of privacy, technology advancement and law enforcement. In several places where cameras have been set up for traffic control, the value has been questioned to point that the cameras have been taken down. We are in a period of deciding between what we can do and what we should do. I suggest reading books like this one to gain enough background to make an informed decision.