Topic: Information Security

Using your favorite programming language implement a program called, My Vernam Cipher. This is based on the Vernam Cipher. You are expected to write the Vernam Cipher which takes English letters as input and output. Your Vernam Cipher must be able to encrypt/decrypt a message and generate a random key or use a key specified by the user.

(50 marks)

12 marks - En with a random key 12 marks - De with a random key 12 marks - En with a user input key 12 marks - De with a user input key 2 marks - Program exit

Sample running of the program:

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Welcome to My Vernam Cipher!

Please select the mode (E encryption/D decryption/X exit): >

E // Press Enter

Please enter the plaintext:

> VERNAMCIPHER // Input can be either lower/uppercase letters with no space; Press Enter

Please select a key (R random/U user input): >

R // Press Enter

---------------------------------------------------------------------------

Plaintext: VERNAMCIPHER

Key: 76 48 16 82 44 3 58 11 60 5 48 88

Cipher text: TAHRSPITXMAB

---------------------------------------------------------------------------

Please select the mode (E encryption/D decryption/X exit):

> D // Press Enter

Please enter the cipher text:

> TAHRSP // Input can be either lower/uppercase letters with no space; Press Enter

Please select a key (R random/U user input):

> U // Press Enter

Please enter the key: > 76 48 16 82 44 3 // A space separates each number; Press Enter

---------------------------------------------------------------------------

Cipher text: TAHRSP

Key: 76 48 16 82 44 3

Plaintext: VERNAM

---------------------------------------------------------------------------

Please select the mode (E encryption/D decryption/X exit):

> D // Press Enter

Please enter the cipher text:

> ABC // Input can be either lower/uppercase letters with no space; Press Enter

Please select a key (R random/U user input): >

R // Press Enter

---------------------------------------------------------------------------

Cipher text: ABC

Key: 89 19 3

Plaintext: PIZ

---------------------------------------------------------------------------

Please select the mode (E encryption/D decryption/X exit):

> X // Press Enter

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Include in your submission any libraries/software components required to run your program. Any program that does not run will be awarded NO marks.