Playfair, Hill Cipher and Security Cases

1. Encrypt the following using playfair cipher using the keyword MONARCHY. “SWARAJ IS MY BIRTH RIGHT”. Use X for blank spaces. 2. Solve using playfair cipher method. Encrypt the word “Semester Result” with the Keyword “Examination”. Discuss the rules to be followed. 3. Perform Encryption and decryption using Hill Cipher for the following Message PEN and Key: ACTIVATED. 4. Perform Encryption using Hill Cipher for the following Message ACT and Key: GYBNQKURP 5. Define the type of security attack in each of the following cases: • A student break’s into a professor’s office to obtain a copy of the next day’s test • A person gives a check of Rs.10 to buy a used book. Later she finds that the check was cashed for Rs. 100 • A person sends 100 mails per day to his / her friend using a phony return e-mail address 6. Which Security mechanism is provided in each of the following cases? • A College demands student ID and Password to log into the College server • A College server disconnects a student if she is logged into the system for more than two hours • A bank requires the customer’s signature for a withdrawal • A Professor refuses to send students their grades by e-mail unless they provide student ID they were preassigned by the professor