Archive for July 27, 2014

Sunday, July 27, 2014

Canvas Fingerprinting Instead of Cookies

Julia Angwin (via John Gordon):

The type of tracking, called canvas fingerprinting, works by instructing the visitor’s web browser to draw a hidden image, and was first documented in a upcoming paper by researchers at Princeton University and KU Leuven University in Belgium. Because each computer draws the image slightly differently, the images can be used to assign each user’s device a number that uniquely identifies it.

Why You Only Have to Wipe a Disk Once

Chris Hoffman (via Uli Kusterer):

To understand why the Gutmann method isn’t necessary for all drives, it’s important to note that the paper and method were designed in 1996, when older hard drive technology was in use. The 35-pass Gutmann method was designed to wipe data from any type of drive, no matter what type of drive it was – everything from current hard disk technology in 1996 to ancient hard disk technology.

As Gutmann himself explained in an epilogue written later, for a modern drive, one wipe (or maybe two, if you like – but certainly not 35) will do just fine[…]

I had not heard that before. However, these days most of my drives are encrypted with FileVault 2, so there’s probably little reason to wipe them, anyway.