3 ms·

OK, IIUC I'd agree that the "entropy" or uniqueness calculation would be misleading if in fact all user agents with a particular string identifier had the same

by jrapdx3 11y ago

OK, IIUC I'd agree that the "entropy" or uniqueness calculation would be misleading if in fact all user agents with a particular string identifier had the same screen resolution. IOW in that case it's redundant information, and therefore would represent only 10 bits of entropy vs. 13. However I imagine keeping track of all correlations of this type would be a big burden for the identifying algorithm. Perhaps it's more practical to sacrifice some accuracy for the sake of expediency. If the goal is determining the probability that this browser is the same browser that previously connected to my server, the estimate just has to be good enough. Additional refinement may simply not have a big enough payoff to make it worth the trouble. Just my view from the sideline...

saurik 11y ago
The "goal" of this website is to educate people about browser fingerprinting, not to provide a practical means for you to fingerprint people on your website. I do not think it is OK if their algorithm is flawed (and I stress "if", as I wanted to open a discussion about whether or not their algorithm is flawed, and was somewhat shocked to end up in an argument that somehow it doesn't matter that the algorithm is flawed ;P), as then they would essentially be using pseudo-science to scare people into believing something; and even if the fear is correct, I'm really a strong believer that the knowledge leading to the fear needs to be accurate or you end up with people making really dumb decisions either at a personal or federal level to try to mitigate the misunderstood problem.
- jrapdx3 11y ago
  I sure didn't intend to be argumentative, and as I said, I do think you are right, the fingerprinting example is flawed just as you point out. I was only considering the calculations in the abstract, as representing how such algorithms might be used by a real entity attempting to track its users. I was putting myself in the place of the tracker and imagining how I'd deal with the issues you brought up. I certainly do not and never have done any such thing on the servers I run in real life. A year or so ago when I was first aware of the Panopticlick site, I was impressed with how easy it was to more or less uniquely identify my browser. I tried numerous ways to make it less unique. Best I could do at the time was reduce the "entropy" from 22 to 15 or so. Even though I knew these results were hypothetical, it was still educational. So the Panopticlick site makes its point even if it's not 100% accurate. How much it scares people is hard to say, but probably not a lot. Bottom line is I've been aware that fingerprinting could be happening, but also not a whole lot to do to reduce my browser's uniqueness. Obviously, it hasn't stopped me from getting on the web anyway.

by jrapdx3 11y ago

saurik 11y ago

The "goal" of this website is to educate people about browser fingerprinting, not to provide a practical means for you to fingerprint people on your website. I do not think it is OK if their algorithm is flawed (and I stress "if", as I wanted to open a discussion about whether or not their algorithm is flawed, and was somewhat shocked to end up in an argument that somehow it doesn't matter that the algorithm is flawed ;P), as then they would essentially be using pseudo-science to scare people into believing something; and even if the fear is correct, I'm really a strong believer that the knowledge leading to the fear needs to be accurate or you end up with people making really dumb decisions either at a personal or federal level to try to mitigate the misunderstood problem.

jrapdx3 11y ago
I sure didn't intend to be argumentative, and as I said, I do think you are right, the fingerprinting example is flawed just as you point out. I was only considering the calculations in the abstract, as representing how such algorithms might be used by a real entity attempting to track its users. I was putting myself in the place of the tracker and imagining how I'd deal with the issues you brought up. I certainly do not and never have done any such thing on the servers I run in real life. A year or so ago when I was first aware of the Panopticlick site, I was impressed with how easy it was to more or less uniquely identify my browser. I tried numerous ways to make it less unique. Best I could do at the time was reduce the "entropy" from 22 to 15 or so. Even though I knew these results were hypothetical, it was still educational. So the Panopticlick site makes its point even if it's not 100% accurate. How much it scares people is hard to say, but probably not a lot. Bottom line is I've been aware that fingerprinting could be happening, but also not a whole lot to do to reduce my browser's uniqueness. Obviously, it hasn't stopped me from getting on the web anyway.