File talk:Knuth-check2.png

Account number
Is it really a good idea to display Donald Knuth's checking account number? Nope. Its a bad idea.

—The preceding unsigned comment was added by Agthorr (talk • contribs) 21:37, 14 May 2006 (UTC)
 * No, it's not. It's fortunate, therefore, that we aren't. Note that the machine-readable numbers at the bottom of the check have been randomly swapped or modified, so that no personal information about Don Knuth's personal bank account is leaked through this image. &mdash;Simetrical (talk • contribs) 05:49, 15 May 2006 (UTC)
 * How are we to verify this? Could you kindly just obscure them? -143.215.155.50 (talk) 09:30, 6 October 2010 (UTC)


 * Hmmm. How about his signature? see  --NealMcB 23:21, 14 August 2006 (UTC)


 * There are thousands and thousands of copies of his signature around: in addition to the checks, people queue after each talk by Knuth to get books signed. It's unlikely to be a problem. Schutz 13:38, 2 January 2007 (UTC)
 * I beg to differ; many intellectuals sign differently for financial transactions. Whether he does so or not is itself a piece of information not worth sharing. -143.215.155.50 (talk) 09:30, 6 October 2010 (UTC)


 * True, the image isn't displaying exactly his account number, but the digits are definitely not "randomly swapped or modified" in any meaningful sense, IMNSHO. I'd feel much more comfortable if the routing and account numbers bore no resemblance at all to the real ones. "No information is leaked" is a very strong claim in a computer-science context! :)
 * Admittedly, the numbers (and signature, and bank logos) are available plenty of other places on the Web, many of them linked from the Knuth reward check article; and Image:Knuth-cheque.jpg apparently has them too; but it would still be a nice gesture to permute the digits a little more, eh? --Quuxplusone 02:27, 2 January 2007 (UTC)
 * If by "random" you mean that the present numbers have been generated by an random generator of uniformly distributed numbers, no it is not the case indeed. "Randomly swapped or modified" means just that: there has been some random swapping and modifying so that the exact number is not there anymore. I have the original image so I can without problem do more changes (which would mean generate new numbers if we follow your suggestion), although if we get there it may be more meaningful (and honest) to replace all numbers by "0" so that it is clear that the numbers are meaningless. I am not sure that it is worth it however — as long as the account number is not readable or deducible from what is in the image, this is probably ok. The bank logos are pixellized anyway, so this should not be a problem. As for the signature, see my comment above. To follow on your "computer science" approach, my question is: what could an attacker gain concretely from the information currently displayed in the check ? Schutz 13:38, 2 January 2007 (UTC)


 * Hmm. I see your point; as long as we don't say exactly how the numbers were permuted, even the information that is leaked doesn't help the attacker much, since only an exact copy of the account number would be useful. (A single-digit error would render it useless, I'd say, although I'm no expert in bank security. :) And given the large number of unpermuted images on the Web, it's not actually protecting the number anyway &mdash; a chain is only as strong as its weakest link, and all that. Anyway, while I still think it would be "polite", or show consideration, or something, to add more randomness, I'm not going to do it myself, and I don't care strongly enough to demand that you do it. :) --Quuxplusone 17:26, 4 January 2007 (UTC)


 * Wouldn't it be easier just to pixelate the routing and account numbers, too? I don't really see the point to permuting them; are you trying to prove that the check is real by showing that there are actual numbers on it? --Evanturner 09:49, 1 May 2007 (UTC)
 * The point is that an image that is half-pixelated is not very interesting to look at. The image already contains quite a few bits that are pixelated; doing the same to all the numbers (a rather large area) would look awful. It's a question of compromise. Schutz 11:50, 25 May 2007 (UTC)
 * I question the value of pixelating the bank logo and the check decorations when the bank name is perfectly legible. And scrambling the bank routing number does nothing useful when you can go to a page like this one  to look up the correct bank routing number.  --206.40.216.242 (talk) 18:48, 29 April 2008 (UTC)
 * The logo and check decorations were obscured because the obscurer thought including them would make the image nonfree (not a problem for a locally-hosted fair use image used only in select articles and justified in an ongoing fashion, but this is on Commons), but looking at the original check I doubt there is sufficient originality for a claim, although we would have to slap the trademark warning on for the logo of the now-defunct America California Bank. Arlo James Barnes 05:20, 16 August 2017 (UTC)