This book is a complete reference on how things are working in "voice and Fax modules," including signal processing aspects, implementations and mapping them to the whole system. Signal Processing for Voice and Fax over VoIP establishes end to end voice-Fax solutions, module description with proper interpretation, practical aspects, measurements, results, and FAQ. This book provides continuity from PSTN to VoIP by providing VoIP infrastructure with diagrams, architectures and examples. The author provides an accessible reference with reasonably simple analysis including diagrams, graphs, tables, practical aspects, server trade-off's and recommendations for voice and Fax. The migration of PSTN to VoIP and the combination of PSTN and VoIP did not happen all across the globe and only a few countries adopted VoIP. This book provides troubleshooting clarity to Voice and Fax over VoIP.