Information Security: Principles and Practices 2nd Edition by Jim Breithaupt, Mark S. Merkow

Exercise 14

More Practice of Decryption Using Substitution

1. Decrypt the following using the substitution method with a rotate value of 13:

PELCGBTENCUL VF SHA

2. What result did you get?

Step 1 of 3

Decrypting cipher text using Substitution method

1. Substitution is a method of encryption and decryption wherein a plaintext is converted into a cipher text and vice versa. This makes the data to be sent more secure as data in encrypted form is difficult to read and understand. Also it is hard to decode.

In substitution method, the basic idea is to replace the letters of the word (data) by some different letters such that it becomes unreadable. The ROT13 cipher is the substitution cipher that replaces each letter of the message by the letter in the alphabet.

Given the cipher text "PELCGBTENCUL VF SHA", needs to be decrypted using Substitution method.