Wireless sensor networks (WSNs) are widely acknowledged for their potential as a robust infrastructure for collecting, processing, and transmitting information. Rezaeipour & Barati proposed a hierarchical key management scheme that manages key creation, distribution, and maintenance to provide services like message confidentiality, integrity, and authenticity to wireless sensor networks. As per the assertions posited by the authors, their scheme purportedly exhibits resilience against a spectrum of potential threats. Nevertheless, upon subjecting their scheme to meticulous scrutiny, our analysis revealed vulnerabilities to manifold adversarial strategies, notably including man-in-the-middle attacks, replay attacks, impersonation attacks, and node capture attacks. This scheme fails to establish a secure session key agreement also. In response to these identified shortcomings, this research devised an “Improved Hierarchical Key Management” (IHKM) Scheme aimed at rectifying the deficiencies of Rezaeipour and Barati’s scheme (RB scheme). This work proposed an enhanced key management scheme that utilizes a blend of symmetric and asymmetric key cryptography to enhance the security parameters of Hierarchical WSNs. A comprehensive security analysis of the proposed work shows that the IHKM scheme is secure against impersonation attacks, man-in-the-middle attacks, replay attacks node capture attacks, Denial-of-Service attacks, and base station bypassing attacks while establishing the mutual key agreement between the area managers and sensor nodes. Moreover, a comparative analysis of the IHKM scheme exhibits notable reductions in energy consumption (62.27% and 49.15%) and memory utilization (39.28%, 23.36%) when compared with the RB scheme and HISCOM schemes respectively. Simultaneously, IHKM contributes to the extension of the network’s overall lifespan by 48.78% as compared to HISCOM scheme and 32.63% as compared to compared with the RB scheme, thereby enhancing the efficiency and longevity of the WSN infrastructure.
