http://www.sans.org/reading_room/whitepapers/authentication/exploration-voice-biometrics_1436
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In 1941, Bell Telephone Laboratories began work on early spectrograms.11 The variation in voices, the very thing which makes voice authentication possible, made it difficult for
researchers to create automated ways of analyzing voices.
In these early days, the research was driven by the potential to use voice technology to track enemy movement via radio traffic. The idea was to identify a
specific voice, note the location of the transmission, and then try to identify the same voice at a later point in time in a new location to determine troop
movements. At that point, the technology was not advanced enough to support this use case, and efforts were frustrating.
As time went on, applications in law
enforcement began to drive the research.
As spectrograph technology improved, enhanced automated analysis began to emerge. Today there is an array of commercial software available that
utilizes automated analysis successfully to accomplish voice authentication.
Banking
Reducing crime at Automated Teller Machines is an ongoing struggle.
Banks have started using biometrics to authenticate users before allowing ATM transactions. Users generally must provide a pin number and a voice sample to
be allowed access.
Royal Canadian Bank is using voice authentication to allow access to telephone banking.
US Social Security Administration
The United States Social Security Administration is using voice authentication to allow employers to report W-2 wages online. Used in
combination with a pin number, the voice authentication provides system security and user convenience.
Law Enforcement
In Louisiana, criminals are kept on a short leash with voice biometrics.
This inexpensive approach allows law enforcement to check in with offenders at random times of the day. The offender must answer the phone and speak a
phrase that is used for authentication. This system guarantees that they are where they are supposed to be!
Voice authentication has also been used in criminal cases, such as rape and murder cases, to verify the identity of an individual in a recorded
conversation.
There is a terrorism application also.
Voice authentication is frequently used to validate the identity of terrorists such as Osama Bin Laden on
recorded conversations. Hopefully these clues will one day assist in his capture.
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