This series is aimed primarily at final year undergraduate and postgraduate students of electronics and computer science, and aims to provide an introduction to research topics in information technology. The series aims to bridge the gap between foundation material covered in the first two years of undergraduate courses and the major research topics within the field of IT. This book covers the topic of computer communications and networking and aims to provide an overview and introduction to this subject. Each chapter is terminated by a summary itemizing the key points contained within, and problems and exercises are provided where appropriate to enable the student to test his knowledge. The book also contains a further reading list of texts and key reference papers covering the field, as well as giving an indication of those journals which publish within the area.