This text aims to help readers gain a better understanding of the technology used in transmission networks. It addresses the future of single wiring architectures for integrated voice, data and video services, discusses the enterprise WAN, the corporate LAN, and the benefits of ATM-based QoS. The book also describes the technical details of hybrid fibre-coax (HFC)-based RF broadband technology and its capability of increasing system capacity at a lower than normal cost. It considers the integration of the public switch telephone network (PSTN) and Internet, as well as the integration of virtual private networks (VPN) with all digital telecommunications into the campus LAN. The text aims to provide a better understanding of the advantages of SONET/ATM technology, and the economic benefits of using single-mode fibre and cable modem technology in the campus backbone and in all trunks.