Comparative Study on Various Authentication Protocols in Wireless Sensor Networks

Wireless Sensor Networks (WSNs) consist of numerous low-power, low-cost sensor nodes deployed in environments where physical monitoring and security are major challenges. Due to their wireless communication medium, dynamic topology, and limited computational resources, WSNs are highly vulnerable to attacks such as spoofing, Sybil attacks, selective forwarding, replay, and node capture. Authentication, therefore, becomes essential to ensure that data originates from legitimate nodes and remains unaltered during transmission. Various authentication mechanisms—including lightweight schemes, symmetric-key approaches, key management systems, and broadcast authentication techniques—have been proposed to address security requirements such as confidentiality, integrity, freshness, and availability. This report provides a comprehensive comparative analysis of major authentication protocols used in WSNs. It studies lightweight authentication schemes, ECC-based approaches, trust-based models, TESLA and µTESLA broadcast authentication systems, and identity-based and one-time signature mechanisms. These protocols are evaluated based on communication and computation overhead, robustness to packet loss, resistance to denial-of-service attacks, scalability, and suitability for real-time applications. The findings highlight that while lightweight schemes excel in energy efficiency, public-key-based mechanisms offer stronger security, and TESLA variants provide scalable broadcast authentication. The study concludes that no single method fulfills all requirements, emphasizing the need for hybrid, adaptive, and energy-efficient authentication mechanisms in future WSN deployments.