In Which Cipher Method Are Values Rearranged Within A Block To Create The Ciphertext?

In Which Cipher Method Are Values Rearranged Within A Block To Create The Ciphertext?

The permutation cipher method will be used, where the values are rearranged within the block in order to create the ciphertext. Today let us know about the permutation cipher method bin detail.

The permutation cipher is also called the transposition cipher. We can also refer to this with the other name called the transposition cipher. Here it describes in a mathematical way to find what going on the ciphertext side. 

The transposition cipher is different from the other two cipher like shift cipher and the substitution cipher.

In the permutation cipher, we don’t actually change the letters that we do as in shift and substitution cipher. Rather we make the letters mute, this means we did not rearrange the letters in the text message.

Let us take an example to understand this concept in detail. Let say a plain text “hello”, the sender wants to send this message to the receiver side who is present far from the sender, now the text message should be encrypted in order to send in a secure manner. Now we encrypt this text message “hello” using the permutation cipher.

Now let us know how this will perform in detail. Before we send the message the sender and receiver must agree to the key, this key is nothing but a path in order to rearrange the letters. But how we are gonna rearrange the letters?

One of the ways to rearrange the letters is we just rearrange the order for the letters in which they are in. This key will help us to rearrange the letters.

Now in the message “hello” we rearrange it to the “LEHOL”. Now, this is called the permutation of the letters. simply we permute the letters of the plain text to make it as the ciphertext.

Now we might have a doubt that how the key will be used in order to permute the letters. For this, we have several different ways in order to perform this.

Every kind of rearranging of the letters will be referred to as a sub cipher.

The change in the order of the characters will be known as the transposition cipher. Let say we have plain text that we need to send to the receiver as “meet me at three pm today at the usual location”. 

Now let try to encrypt this kind of message, now the encoded message will be as MTMASC EHTTUA EROTAT TEDHLI AEAELO TPYUON.

Now we write this plain text in the form of 

  M E E T A T  

 T H R E E P

 M T O D A Y 

A T T H E U

S U A L L O

C A T I O N

Now, we encrypt the message by taking all the letters of the columns that are present. and hence the encrypted message will ve mtmasc ehttua erotat tedhli aeaelo tpyuon. We combine the letters in a column way and send them to the receiver.