The risk of interception either of a biometric itself as it travels across a network, or of the authentication message issued when a correct biometric has been presented means that using biometrics as a form of authentication on open networks such as the Internet is hugely problematic, because such messages could subsequently be forged.

ECONOMIST: The measure of man | The

For buildings that require additional security, like government offices, the keys can be combined with other forms of authentication, such as PIN numbers or biometrics.

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The banks have also been experimenting with more sophisticated forms of user authentication, including fingerprinting, iris-scans and biometrics.

ECONOMIST: Your flexible foe

The Biometrics assure the iWatch wearer is the authenticated user and provides an additional layer of authentication, which could be very important across the board from enterprise to personal security.

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