Comp 3704
Introduction to Cryptography
Homework 3
Due Tuesday, January 28, 2003

1. Encode a short text using a Hill cipher. Give me the plaintext, the matrix used for the key, the ciphertext, and the matrix to use for decryption.
2. Encode a short text using a permutation cipher. Give me the plaintext, the permutation used, the ciphertext, and the permutation I should use to decrypt. Also give me the encryption key and decryption key in matrix form.
3. Do problem 1.16 from the text
4. Do problems 1.6 and 1.11(a) from the text
5. Say that you know that a Hill cipher with m=2 was used to encode the plaintext "east wind rain", resulting in the ciphertext "UIPPKQIJHIBD". Use this information to decrypt the ciphertext "KMMGVHRV", which was encrypted with the same key.
6. Extra credit: Problem 1.11(b) and 1.11(c) from the text.
7. Extra credit: Problem 1.12 from the text.