Depending on voice transmission mechanism, this book categorized VoWSN applications into two categories: VoWSN based on voice streaming system and VoWSN based on Automatic Speech Recognition (ASR) system. However, supporting Real-Time voice transferring using low cost, resource - limit sensor networks, is never a trivial task as it represents a demanding process in term of memory storage, CPU utilization and bandwidth utilization. So, in this book we aimed to deploy the two categories, analyze and compare between their performance to select the mechanism that gives the satisfied performance then suggest the suitable solutions to enhance this performance.