Secure and Efficient Lightweight Authentication Mechanism for Constrained IoT Networks

With the rapid expansion of the Internet of Things (IoT) networks, ensuring secure, efficient, and high-performance device communication has become increasingly critical. Existing lightweight authentication protocols struggle to balance security, performance, and efficiency. To address this, we propose OPP (Our Proposed Protocol), a lightweight authentication protocol integrating session-specific AEAD encryption and ECC-based Schnorr signatures to strengthen security without degrading performance and efficiency. OPP is rigorously evaluated against SELAP and ELWSCAS through formal (Scyther) and informal security analyses, and performance simulations in NS-3 using metrics such as delay, packet delivery ratio (PDR), throughput, energy, computation, and communication cost. Results demonstrate that OPP achieves mutual authentication, session key freshness, and best attack resistance while outperforming counterparts in performance, achieving the lowest handshake delay (11.53–29.50 ms), highest PDR (91.20–98.40%), and best throughput (72–412 authentications). It also sustains minimal energy consumption (0.320J at 50 nodes), low communication overhead (960 bits), and efficient computation (705 µs). Since SELAP and ELWSCAS previously outperformed earlier schemes, OPP’s superiority implies a transitive improvement over existing IoT authentication protocols, establishing it as a robust and scalable solution for secure communication in constrained IoT networks.