Over the last ten years, many ISP companies have sprung into existence and now compete massively for customers. In addition, practically all the "old" telephone companies have entered the ISP market, either directly or via sub companies. Due to the dramatic increase in competition, it has become increasingly important for ISPs to run an efficient and cost--effective business. This exciting new publication sets out to provide guidance for those seeking to do just that, in a comprehensive reference that draws on state--of--the--art research in network technology. It stresses the need for the ISP to differentiate itself from its competitors by clearly defining the criteria, which will enable to operate with the greatest efficiency and deliver the highest Quality of Service. Contrary to most books on the market, this text does not only focus on IETF (Internet Engineering Taskforce)--based Quality of Service approaches, but rather offers a comparative evaluation of different methods as they are discussed in the research community. Those at the forefront of network technology research will also find this a valuable reference tool which discusses the latest scientific methods such as queuing theory, dynamic programming, robust optimization theory, and illustrates all examples using numerous mathematical models and simulations. Aims to differentiate itself from the majority of technical guides on ISPs and Internet Exchange Points, by focusing on the key implementation issues of efficiency and Quality of Service. Looks at operating a network, connecting it to other networks (interconnections) and planning the expansion of such a network from an economic and traffic--engineering angle (QoS, reliability, costs). Presents state--of--the--art research in network science, exploring issues such as queuing theory, dynamic programming and robust optimization theory. Provides a comprehensive, practical guide to aid decision makers in the industry, using a comparative approach amply illustrated with mathematical models and simulations. Explores the future of ISPs, with the possibilities opened up with the arrival of new applications and the potential to exploit existing ones (for example video streaming and telephony).