Question: Problem 2. Write computer programs for the Permutation Cipher based on Z2g as in Problem 1. In encryption program, the inputs are a value of

 Problem 2. Write computer programs for the Permutation Cipher based on

Problem 2. Write computer programs for the Permutation Cipher based on Z2g as in Problem 1. In encryption program, the inputs are a value of m (the size of permutation), a permutation as the key and the plaintext, and the output is the ciphertext. Write the decryption program accordingly. Try your programs by some text. Note that since 1 m and the length of plaintext is not fixed, paddings might be added to the end of plaintext by the program. You may think about what kind padding is better for the security and design your paddings. Problem 3. Write an algorithm to perform known-plaintext attack on Permutation Cipher. This algorithm can be used to determine the length of the permutation m and the key permutation. Use this algorithm to attack the system in Problem 2: by inputting a plaintext and the according cipher text from Problem 2, your program should output the value of m and the permutation (the key). Problem 2. Write computer programs for the Permutation Cipher based on Z2g as in Problem 1. In encryption program, the inputs are a value of m (the size of permutation), a permutation as the key and the plaintext, and the output is the ciphertext. Write the decryption program accordingly. Try your programs by some text. Note that since 1 m and the length of plaintext is not fixed, paddings might be added to the end of plaintext by the program. You may think about what kind padding is better for the security and design your paddings. Problem 3. Write an algorithm to perform known-plaintext attack on Permutation Cipher. This algorithm can be used to determine the length of the permutation m and the key permutation. Use this algorithm to attack the system in Problem 2: by inputting a plaintext and the according cipher text from Problem 2, your program should output the value of m and the permutation (the key)

Step by Step Solution

There are 3 Steps involved in it

1 Expert Approved Answer
Step: 1 Unlock blur-text-image
Question Has Been Solved by an Expert!

Get step-by-step solutions from verified subject matter experts

Step: 2 Unlock
Step: 3 Unlock

Students Have Also Explored These Related Databases Questions!