Technology for Communications Professionals is a three-volume set designed to provide the Communications Professional with a foundational knowledge of the technology used to enable communications on the public network. The intent of this series is to provide the fundamental concepts and functions upon which communications products and services will operate over the next several decades. The intervention of the Internet and packet-based networks has tipped the legacy telecom business on it's head. The next generation network transitions from a synchronous, big-system hardware-oriented network consisting of a complex core supporting simple end-user devices (telephone) to an asynchronous, software-oriented distributed processing network, simple core which relies on complex end-user devices (computer). The first volume in this series is called Packets and Voice. This book examines the basic structure of packet networks. We discuss packet structure and addressing as well a discussion of routers, routing systems, and an introduction to Quality of Service functions. Part two of this book examines Voice over IP. We discuss voice sampling, quantization, and various issues encountered when supporting voice services over a packet network. We encourage all to focus and complete the exercise questions. The answers are in the back of the book. The time required to complete those questions is minimal and they help you determine your understanding of the topics.