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How can I compare different cipher text? When deciphered, say the same thing. I would like to find out the ciphering method. Any help would be appreciated. Thanks.

The primary code needs to be a 8 characters. The cipher formula then spits out different 20 character Hex codes. Would giving the Hex codes and original code help?

Adi
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Adi
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  • Welcome to Cryptogtaphy.SE. Your question is not clear. What do you want to achive? ECB mode can compare the equality, however, it is insecure. [There are Fully Homomorphic schemes that one can compare the equality of the ciphertext, however, the result will be encrypted, too.](https://crypto.stackexchange.com/q/63781/18298) – kelalaka Jan 14 '22 at 18:00

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I have 4 different cipher texts, looks like Hex, that when deciphered come to the same pre-ciphered text. I would like to find out how the pre-ciphered text was ciphered.

Unless the cipher is weak (either deliberately in a Capture-The-Flag challenge, or it's a homebrew cipher), you have no chance.

Any cipher we would trust will generate ciphertext that looks completely random (and that's pretty much one of the criteria we use on whether a cipher is trustworthy - if it's distinguishable from random, it isn't), and that remains true even if we get to pick the plaintext which is encrypted.

Given that the ciphertexts look random, that randomness doesn't give us any information to learn what the cipher was (unless there's some metadata in the clear that tells us, for example, the negotiated ciphersuites that appear in the cleartext TLS client/server hellos).

poncho
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