Within World War I, the Germans used a double-columnar transposition cipher called Übchi. It is a columnar transposition cipher, and uses a double columnar transposition.
With the Ubchi cipher, we determine the number of characters in a key and use this to define a number of column. Then we layout the plaintext into these columns, and then order the columns in an alphabet may defined by the keys. Next, we read the ciphertext back by…
