CryptoLab: How I turned a cryptography protocols lab into a testbed with Alice, Bob, and Mallory

An instructor has developed 'CryptoLab,' an educational testbed for a 'Cryptographic Protocols' course, designed to move beyond basic encryption implementation toward practical attack analysis. Instead of simply calling AES-GCM library functions, students work in an interactive environment where an active adversary (Mallory) is placed between the sender (Alice) and the receiver (Bob). The platform allows students to visualize the consequences of modifying encrypted packets, reusing nonces, and handling key revocation. The author emphasizes that this approach helps students better understand protocol vulnerabilities and attacker logic. The article details the architecture of the first lab session and provides examples of key experiments aimed at fostering a deeper understanding of cryptography through practical threat modeling.