Privacy-Preserving ECC-Based AKA for Resource-Constrained IoT Sensor Networks with Forgotten Password Reset.

Wireless sensor networks (WSNs) are extensively used in IoT applications. Secure access control and data protection are essential. Nonetheless, the wireless environment has an open nature. The limited resources of sensor devices render WSNs susceptible to a variety of security attacks, causing significant difficulties in the design phase of efficient authentication and key agreement (AKA) protocols. This study proposes a physically unclonable function (PUF)-based lightweight and secure AKA protocol for WSNs based on elliptic curve cryptography (ECC). A secure password update scheme is offered, which would allow legitimate users to reset forgotten passwords without re-registration. According to formal security analysis using BAN logic and ProVerif, the proposed protocol is secure against common attacks. Moreover, from an entropy perspective, the use of dynamic pseudonyms and fresh session randomness increase an adversary's uncertainty about user identities, thereby limiting identity-related information leakage. Performance evaluation shows that the proposed protocol achieves lower computational and communication overhead than the existing ones, making it suitable for WSNs with resource constraints.