Abstract: The breakneck growth of the Internet of Things (IoT) has led to the proliferation of low-power communication protocols like MQTT, CoAP, and AMQP. Yet, all these current protocols have severe drawbacks: high energy consumption, high overheads from security measures, and unresponsiveness to congestion. To cope with these challenges, this paper presents the Adaptive Secure Energy-Efficient IoT Protocol (ASEIP), a new communication protocol that combines energy-conscious forwarding, light encryption, and adaptive congestion control. ASEIP uses a hybrid reliability mechanism that distinguishes between critical and non-critical data streams, thus trading off energy efficiency and reliable delivery. The protocol is executed and tested through the NetSim simulator, and its performance is compared with MQTT, CoAP, and AMQP under different traffic conditions and node concentrations. Simulation results show that ASEIP obtains up to 25% increased throughput, 18% reduced end-to-end delay, and 30% less energy consumption with comparable reliability. The results confirm ASEIP as a strong contender for large-scale IoT applications under resource-limited environments in areas like healthcare, smart cities, and environmental monitoring.

Key words: IoT protocol, NetSim, adaptive congestion control, lightweight security, energy-aware routing, performance analysis