Fixed-state ciphers vulnerable to side channel analysis attacks

Ryan Carboni ryacko at
Sat May 6 20:05:19 PDT 2017

The simplest error correction code is a repetition code. This has escaped
many peoples attention.
" The frequency at which a key should be changed in order to maintain an
minimum level of protection depending on the number of unrolled rounds
computed per cycle is explored."

Here some attacks were made against Simon and Speck.

In my lay opinion, RC4 is more secure for the internet of things. The
greatest vulnerability for computers is memory bound errors, not... uh.
Malicious javascript sending a DDOS on an 100 megabit uplink to a server so
a passive adversary can collect ciphertexts and do statistical analysis.
Naturally everyone says that no one was fired for using AES, but who was
fired for not putting a password on a database?

I think if the RC4 round function was applied key length bytes more times
(128-bit key, 16 more key schedule rounds), the first few bytes will have
less bias, and the only related key recovery attacks apply to the first few
An additional xor to mask the output or input of a byte lookup may improve
Or use an ARX cipher as a NLFSR, like the Lex cipher.

In any case, don't use error correction codes in cryptography.

This is some kinda multidimensional chess.
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