Text cipher option that can decrypt the same ciphertext to two DIFFERENT and DESIRED outputs given DIFFERENT keys (and/or alphabet)
I've been thinking about this for a while and I can only think of one possible solution.
If you want to share two different messages with the same cypher text then you might be able to use a &quot;one-time pad&quot; with multiple decryption possibilities, or rather multiple one-time pads for the same text.
So if I were to have the following cypher text
GTEROSDFEE
Each one-time pad takes individual letters in the cypher text and assigns an other letter;
Thus, with the same cypher text, with one one-time pad I would get
HELLOTHERE
(pad: G-&gt;H, T-&gt;E, E-&gt;L, R-&gt;L, O-&gt;O etc.)
And with an other one-time pad I would get
GOODBYEYOU
(pad: G-&gt;G, T-&gt;O, E-&gt;O, R-&gt;D, O-&gt;B etc.)
This can be practical for short messages that do not use too many characters, as to decrypt you must know the unique decryption for each individual column of characters of text.