Encryption/decryption algorithms

1 What is the difference between the AES decryption algorithm and the equivalent inverse cipher?

2 What is triple encryption?

3 What is a meet-in-the-middle attack?

4 How many keys are used in triple encryption?

5 Why is the middle portion of 3DES a decryption rather than an encryption?

1 Briefly describe MixColumns.

2 Briefly describe AddRoundKey.

3 Briefly describe the key expansion algorithm.

4 What is the difference between SubBytes and SubWord?

5 What is the difference between ShiftRows and RotWord?

Solution: