Cool Technology: Fingerprinting your PC

Tracking PCs anywhere on the Net
Published: March 4, 2005, 10:56 AM PST
By Renai LeMay, Special to CNET News.com


A University of California researcher says he has found a way to identify computer hardware remotely, a technique that could potentially unmask anonymous Web surfers by bypassing some common security techniques.

Tadayoshi Kohno, a doctoral student, wrote in a paper on his research: "There are now a number of powerful techniques for remote operating system fingerprinting, that is, remotely determining the operating systems of devices on the Internet. We push this idea further and introduce the notion of remote physical device fingerprinting...without the fingerprinted device's known cooperation."

The potential applications for Kohno's technique are far-reaching. For example, it could be possible to track "a physical device as it connects to the Internet from different access points, counting the number of devices behind a NAT even when the devices use constant or random IP identifications, remotely probing a block of addresses to determine if the addresses correspond to virtual hosts."