Classical Encryption Techniques

                           Classical Encryption Techniques

• A substitution technique is one in which the letters of plaintext are replaced by other letters or by number or symbols.  


• A very different kind of mapping is achieved by performing some sort of permutation on the plaintext letters. 


• This technique is referred to as a transposition cipher. 


• The methods of steganography conceals the existence of the message, whereas the methods of cryptography render the message unintelligible to outsiders by various transformations of the text. 


• In cryptography, a permutation box (or P - box)  is a method of bit-shuffling used to permutation box (or P-box) is a method of bit-shuffling used to permute or transpose bits across S-boxes inputs, retaining diffusion while transposing.

Keywords:

Plain Text    : Original Message

Cipher Text  : Scrambled Message