In this book, focuses on the world of the ISP and in particular on the efficiency of their network operation and on the QoS that they (aim to) provide. Structures the book into four parts, namely the ISP market, network architecture, interconnection issues, and traffic and network engineering. In that way he situates descriptions of the technology issues and emerging solutions in their proper context. New strategies and insights are presented that can help ISPs realise their QoS targets.