Fingerprinting Computers – Part I – Your browser.

Authentication is about the only big open problem in the practice of internet security. The existing encryption and hashing algorithms as well as the key generation/management protocols offer a high degree of security, barring programming/implementation errors.
Authentication technologies face serious challenges mainly because identity is difficult to establish with a 100% certainty even using physical characteristics, i.e., signatures and credentials can be forged, the physical appearance of people can be manipulated, etc.
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