New positional cipher, Unbreakable???

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  • 2 weeks later...

A couple of thoughts... if you have repeated characters and you can choose different positions then when you re-run the encryption you could reveal which characters are the same. If the plain text is English then we could expect the most duplicated characters to be the letter E, and the least duplicated to be letters such as Q and Z, and then just test out different character mapping arrangements.

However I don't fully understand the decryption process... if you give me the key of XYZ and positions 2,1,4,3,5 how do I know which letter a position relates to unless it is in the key. How do I come up with A, B or C? Or does the key have to contain all the unique letters of the plain text?

Also, with the key embedded, I am just wondering about forward secrecy implications.

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A video explaining decryption of the positional cipher

With multiple passes the cipher text can equal any one of the numbers or letters of the key. Meaning the key length only needs to be as long as all letters or numbers used. Not as long as the plaintext.



Edited by 2muchcoffee
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This is a very flexible cipher. It can be used as an encryption algorythim, as a random number generator, and a way to test  randomness of a prng (I know that will make you cringe but please look at it before you come to an opinion). The sample was taken from a prng found here for medical purposes from this site( Excel sheet named prng histogram at the link or click here.

Next video will be how to use this alg. as a prng.

Edited by 2muchcoffee
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