Symmetric Key Encryption
Triple DES (3DES)
- Can be done with 2 keys for 112-bit effective key length
- Encryption
- Encrypt block with first key
- Decrypt (yes, decrypt) result with second key
- Encrypt result with first key again; Send this ciphertext
- Decryption
- Decrypt received ciphertext with first key
- Encrypt (yes, encrypt) result with second key
- Decrypt result with first key again