The following ciphertexts are protected using encryption algorithm:

i) B EHOX VKRIMH UXVTNLX BM BL VATEEXGZBGZ UNM YNG MH EXTKG

ii) MSUTBDPDEGABFHMTOQRCMAESCAPNALZUMSHZVTYDHQFVKX

a. Attack each of the above cipher-text and provide the deciphered-plain text. You may use paper and pen method, use any software you may find, or write your own software in making the attack success. Describe the utilized methods (such as brute force, letter frequency, statistical analysis, etc.) for deciphering purposes and identify the encryption algorithm used for the ciphertext. In addition, state the reason(s) for choosing the particular deciphering method. (Hint: the plaintext is in English.)

Note that a correct decipherment without an explanation will receive ZERO mark. The task is to describe the decryption / attack process, the method used and lastly showing the recovered plaintext.

[20 marks]

b. What do you understand in terms of their (i)-(ii) strength and weakness? Explain briefly in not more than five or six lines.

[5 marks]