My Bank is using Biometrics :-0
I recently visited my Bank to get a replacement credit card as mine was compromised. As expected, I was required to present my fingerprints as part of the Bank’s identity verification process. For some reason, the online verification system could not find a fingerprint match and the Bank had to revert to traditional methods to confirm my identity.
Being in the biometrics industry for many years, I found this very strange, as I knew my fingerprint quality is exceptional. We at Ideco therefore decided to investigate the matter in more detail. We obtained a similar fingerprint scanner the Bank is using to do some comparative tests. So what did we find?
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The picture on the left was obtained using a conventional True Reflective Imaging (TRI) fingerprint scanner. Any experienced fingerprint expert will agree with me that this is a good quality print. The fingerprint ridges, core and delta are clearly visible. The contrast is obvious and even the sweat pores are noticeable. Most fingerprint identification systems will be able to easily assign the matching points with a high level of accuracy.
The picture on the right is of the same finger, but was obtained using a Multi-Spectral Imaging (MSI) scanner similar to that used by my Bank. Besides the obvious difference in capture size, this image seems to be out of focus and smudged with many artefacts. In many areas the fingerprint ridges look inverted and all the crisp detail is missing. One can even argue that there is another picture superimposed on this image.
Looking closer at Multi-Spectral fingerprint scanners, they are designed to use various wavelengths of light during fingerprint capture. This allows the scanner to both read the fingerprint surface information, as well as the sub-dermal information below the skin. According to the product brochures the advantage is that these scanner can “see” through dirt or moist on the fingerprint. But that obviously comes at the expense of having good image quality.
So what did the experts* have to say about this technology and its results:
- According to research done by the University of Colorado at Colorado Springs, spatial processing of fingerprints (looking beyond the two dimensional surface image) will produce different artefacts on different measurements. It is therefore impossible to produce a consistent image over time and customers may have to be re-enrolled on a regular basis;
- According to the primary supplier of the Automated Fingerprint Identification System (AFIS) used by our Department of Home Affairs, if the fingerprint images do not meet the international Image Quality Standards there is a high risk of false acceptance or failing to identify the person;
- According to the South African Police Services Criminal Record Centre, fingerprints obtained from these devices are not suitable for processing against their criminal database as part of the criminal investigation process; and
- According to a Senior Fingerprint Experts, with years of experience in the criminal justice system, it would be impossible to use these fingerprint images as evidence in a Court of Law.
It is standard practice in South Africa for financial institutions to verify fingerprints against the national fingerprints database of our Department of Home Affairs. This is mandated by legislation in an attempt to prevent identity fraud and/or money laundering.
Is it not ironic that my Bank would procure fingerprint scanners that could not support these efforts, and would count useless in prosecuting the villains? One thing I have confirmed, my fingerprints do match effortlessly against the Home Affairs database when using a conventional TRI fingerprint scanner.
*For obvious reasons these experts prefer to stay anonymous. Please contact me directly for further information.