Practical 2 — CrypTool and HashCalc

Aim
Explore classical ciphers and hash calculation using CrypTool / HashCalc.

STEPS
1. Open CrypTool and select a symmetric/classical algorithm.
2. Try Caesar, Vigenère, Hill and Playfair ciphers with sample plaintext and key.
3. Encrypt the text; record ciphertext. Decrypt it using the same key and verify the original.
4. In HashCalc, select a hash algorithm, enter text or choose a file, calculate and record the digest.

Key points
- Caesar uses a fixed alphabet shift.
- Vigenère uses a repeating keyword.
- Hill uses matrix operations modulo 26.
- Playfair encrypts letter pairs.
- Hashes are used to check data integrity; they are not encryption.
