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A comment on Bunny.py: A WiFi darknet that hides its traffic in the noise of 802.11. Parent comment

Re:Bunny.py: A WiFi darknet that hides its traffic in the no... by marshray on Thursday May 16, 2013 @04:16PM (#5720890)
It's not the -4 that's weird, it's the modulus and remainder with floating point arithmetic.
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Re:Bunny.py: A WiFi darknet that hides its traffic in the no... by andrewcooke on Thursday May 16, 2013 @05:17PM (#5721201)
agree it's odd, but it's basically 100 * (len - 4) % 121 = 85

(I think?)

(yes, I know about rounding, fractions, different bases - I was just trying to explain why it still worked. sigh.)

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Re:Bunny.py: A WiFi darknet that hides its traffic in the no... by marshray on Thursday May 16, 2013 @05:49PM (#5721397)
No, actually they're different. http://floating-point-gui.de/ http://web.cse.msu.edu/~cse320/Documents/FloatingPoint.pdf

If you know enough about floating point to prove that the rounding will always give you the correct answer, then probably you would have just used the integer representation to begin with.

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