A broad introductory text written for computer scientists and engineers, focusing on the fundamental aspects of data communications and computer networks. This second edition has been thoroughly revised to cover current networking issues and technologies. Specific updates include those on networks and their management, transmission technologies, security and encryption. This text is appropriate for modular courses in data communications as well as computer science. It is also a useful source for professionals in related disciplines. Key features of this edition: Unique and accessible overview of networking. Includes modern networking issues - management, security and encryption. Enhanced treatment of core network technologies including ATM and SDH/SONET . New chapter on TCP/IP. Focuses on the engineering aspects of data communications. Covers international standards, with emphasis on those for Europe and North America. Numerous worked examples designed to improve the understanding of key principles Michael Duck is a professional engineer at Nortel Networks, UK. Richard Read is a Senior Lecturer in Computer Communications at Middlesex University and a freelance consultant