TRANSPOSITION CIPHER WITH PSEUDO-RANDOM SHUFFLING: THE DYNAMIC TRANSPOSITION COMBINER
Terry Ritter · Cryptologia · 1991
Extensions are made to a class of transposition cipher based on continued shuffling. These ciphers permute plaintext into ciphertext by swapping every message element with some message element selected at pseudo-random; elements can be characters (e.g., bytes) or bits. Extensions include operation on very large data blocks, cryptographic shuffling variations, and the efficient extraction of plaintext from ciphertext. In addition, selected extra data can be adjoined to the plaintext to eliminate the data-dependent weak encipherings otherwise inherent in transposition. This bit-balancing data is supposed to completely eliminate all normal usage-frequency statistics from bit-transposition ciphertext. The same mechanism can also be viewed as a cryptographic combiner, and, with sequence-to-block and block-to-sequence conversions, can generally replace the exclusive-OR combining function used in Vernam stream ciphers.