Reliability and Security Analysis of Active RIS-Assisted IoT NOMA Networks Over Nakagami- <i>m</i> Fading Channels

Ensuring reliable transmission and secure communication remains a critical challenge for next-generation wireless networks, particularly in the context of sixth-generation (6G) and Internet of Things (IoT) systems. This paper investigates the reliability and physical layer security of active reconfigurable intelligent surface (ARIS)-assisted dual-hop relaying in non-orthogonal multiple access (NOMA) networks over Nakagami-mfading channels. We develop a comprehensive system model where a base station communicates with two users via a relay and an ARIS, in the presence of a potential eavesdropper. Closed-form expressions for outage probability (OP) and intercept probability (IP) are derived for both near and far users, capturing the effects of ARIS configuration, power allocation, and channel fading. Extensive Monte Carlo simulations confirm the accuracy of the analytical results and reveal that increasing the number of ARIS elements, optimizing amplification factors, and carefully allocating power can significantly enhance both reliability and secrecy performance. The findings provide valuable insights for the design of robust and secure ARIS-assisted NOMA networks in practical wireless environments.