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TAbdiukov/thoughts_on_keccakmod.txt

Created April 5, 2019 22:57
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thoughts on keccakmod used in NetComm censor
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thoughts_on_keccakmod.txt
1. SHA3_224 => 224 bits
2. 224 (bits) [/8] = 28 (bytes)
3. 28 bytes [*2] = 56 (HEX places occupied) = 56 (-long String after digestion)
4. 56 String of HEXadecimals => max number is FFFF...FFFF (56 times). This number is:
(10 (base 16) ^ 57) - 1 = (16^57)-1
5. To find maximum String length base 62 (keccakmod), will use latural logs (coz idk how else). Do:
floor( ln((16^57)-1) / ln(62) ) + 1 ~= floor(158.037 / 4.127) + 1 ~= floor(38.292) + 1 = 38+1=39
* 39 is the maximum code length in Base62
* Minimal code length is trivial: 0000...0000 (56 times) = 0 which representable in 1 digit
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