December 1998

When Fingerprints Mean Identity

By Cran Sin

     Thanks to the new technology known as biometrics verification, one can now withdraw money from automatic teller machine even if he or she forgets the password.

     With this technology, one's identity can be verified by biometrics.

     Biometrics are unique parts of the body and behaviour which can be divided into two groups - physical and behavioural.

     Physical biometrics are the inborn characteristics of a person, such as fingerprints, iris, retina, face, hand shape, DNA and body odour, while examples of behavioural biometrics include autograph and voice.

     For example, iris recognition actually makes use of the unique pattern of blood vessels over the surface of the eyeball around the iris. The user is defined as valid if the input biometrics match with the previously encoded record.

     Dr. Yeung Dit Yan, associate professor of the Department of Computer Science of the Hong Kong University of Science and Technology, has conducted intensive research on biological verification since 1994.

     According to Dr. Yeung, this technology means a great step forward for the security industry.

     "It is extremely difficult to fake or copy others' biometrics," he said.

     Even a photocopy of a valid user's fingerprints cannot deceive the machine.

     Said he: "This will not work as the machine scans a three-dimensional image of the fingers rather than a plane one."

     As a result, biometrics verification helps us avoid being cheated by our own eyes.

     "This is what biometrics mean," Dr. Yeung said. "Everyone is unique. We may not be able to spot the differences between identical twins who look a hundred percent alike, except for technology."

     However, there are some problems in using biometrics verification method.

     Explained Dr. Yeung: "You can be rejected by the computer even if you are a valid user.

     "It may be due to the wrong angle of scanning the fingerprints, which makes them look different from the computer record."

     Besides, biometrics can be affected by many other factors.

     For example, dry weather will cause a cast of skin, which impairs the function of the finger scanner. Having the flu will also affect the voice, thus fails voice recognition.

     Poly Security System Limited is a local pioneer, which provides finger scanning and iris recognition systems for its clients.

     However, its director, Mr. Daniel Tsoi, doubts the development potential of these new security systems, as it is a technology "far too new".

     Said he: "So far, there is no order for finger scanners for residential use, nor demand for iris recognition systems.

     "An obstacle to their popularity is that the local security companies are not yet ready to provide technical support.

     "Obviously, people still prefer to stick to the traditional machines."

     Price is another problem. While a card reader system costs only about $15,000, the price of a finger scanning system is nearly $30,000.

     "I personally think that they're still inconvenient to use," said Mr. Tsio, "You have to touch the scanner's window very carefully as a little disposition will cause rejection."

     "Also, some people are afraid that their eyes would get hurt when they use the iris recognition system," he added.

     Despite the public's attitude, Dr. Yeung Dit Yan of HKUST still believes that biometrics verification methods will soon be widely accepted and applied.

     "Some of the biometrics verification methods have already developed into a mature stage, and they are ready for use," said he. "We will enter a new era - an era when biometrics mean your identity."