This book explores innovative approaches for optimizing energy consumption in dynamic routing protocols within heterogeneous wireless sensor networks (WSNs). It introduces an Energy-Efficient Delay-Sensitive Technique (EEDST) designed to enhance network performance by reducing power consumption while ensuring minimal data transmission delay.The book delves into key concepts such as energy-aware routing, heterogeneous network architecture, delay-sensitive data transmission, and performance metrics for WSNs. It provides a comparative analysis of existing techniques, highlighting the advantages of the proposed methodology in improving network longevity and efficiency. Through theoretical frameworks, simulations, and real-world applications, this book serves as a valuable resource for researchers, engineers, and professionals working in the field of wireless sensor networks and IoT-based systems.