The book identifies the performance challenges concerning Wireless Sensor Networks (WSN) and Radio Frequency Identification (RFID) and analyzes their impact on the performance of routing prools. It presents a thorough literature survey to identify the issues affecting routing prool performance, as well as a mathematical model for calculating the end-to-end delays of the routing prool ACQUIRE; a comparison of two routing prools (ACQUIRE and DIRECTED DIFFUSION) is also provided for evaluation purposes. On the basis of the results and literature review, recommendations are made for better selection of prools regarding the nature of the respective application and related challenges. In addition, this book covers a proposed simulator that integrates both RFID and WSN technologies. Therefore, the manuscript is divided in two major parts: an integrated architecture of smart nodes, and a power-optimized prool for query and information interchange.