Vigenère Cipher

 Q1.             

        Encrypt & decrypt the below mentioned message                  

        Plaintext: How are You?

        Key: FineMethod: Vigenère Cipher (Using Table) 

To encrypt and decrypt the plaintext "How are You?" using the Vigenère Cipher with the key "Fine" and the Vigenère Table, follow these steps:

Write out the plaintext and the key underneath each other, repeating the key as necessary to match the length of the plaintext:

Plaintext: H o w   a r e   Y o u ?

Key:         F i n e F i n e F i n 

Use the Vigenère Table to find the corresponding ciphertext letters for each letter in the plaintext. To do this, find the row for the key letter and the column for the plaintext letter, and write down the letter at the intersection of the row and column.

The resulting ciphertext is "MWJ AZR DWH".