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Re: crypto technique
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One question before I work on this more at a later date.
Can you still decode properly if you take the modulus of each
coefficient? I ask since if you can't, the modulus makes is harder to
find the constants, but as a side effect it also destroys the message.
Say I use
f = 29/2 x + 40
g = 135/2 f^2 + 135/2 f + 75
I get g = 110775 + 317155/4 x + 113535/8 x^2
This is easy to solve, so Matt takes the modulus of each coefficient
(some power of 2, I pick 32 here to keep it simple).
results in g' = 23 + 99/4 x + 127/8 x^2
Say I encode my message x = 5
g(5) = 6895725/8 mod 32 = 109/8
g'(5) = 4349/8 mod 32 = 253/8
Notice that these two results aren't equal at all!
Am I misunderstanding the encoding (and decoding) process? Aren't
these two results supposed to be equal? I'm not getting the expected
result when each coefficient is reduced mod 32.
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--
Karl L. Barrus: [email protected]
keyID: 5AD633 hash: D1 59 9D 48 72 E9 19 D5 3D F3 93 7E 81 B5 CC 32
"One man's mnemonic is another man's cryptography"
- my compilers prof discussing file naming in public directories