AES-GCM

This paper presents a cryptographic user authentication protocol based on AES in Galois/Counter Mode (GCM) and key derivation using PBKDF2-HMAC-SHA256. The proposed scheme follows a challenge–response model and ensures confidentiality, integrity, and authenticity of transmitted data without disclosing or storing the password in plaintext. A client-server architecture was implemented, with the backend developed in Flask (Python) and the frontend in JavaScript. The protocol incorporates nonce usage, authentication tag verification, and protection against replay and brute-force attacks.

The article compares the performance and memory requirements of AES-GCM and ChaCha20Poly1305 AED encryption solutions for typical 8/16/32-bit embedded low-end processors in the Internet of Things device with different approaches to providing tolerance to Timing Attacks and Simple Power Analysis Attacks. Particular attention is given to the low-level multiplication implementation in GF(2128) with constant execution time as a key GCM operation, since low-end processors do not have ready instructions for carry-less multiplication.