This comprehensive book uses a unique modular approach to present the most current data communications information available. A vignette opens each chapter and raises issues that must be resolved using information covered in it. The book begins with quality of service, Internet standards and small PC networks on simple LANs. It contains current material on the Internet and TCP/IP, and integrates Telephony (hierarchial circuit switching, IP telephony, and cellular service) into the core chapters. There is a strong focus on LAN switching, (which now dominates in large LANs), and a full up-to-date chapter on security (SSL, IPsec, Kerberos, etc.). Other chapter highlights include frame relay, Internet access (including ADSL and cable modems), web-host integration, IBM mainframe systems, and SNA. An analysis of alternative products covers Net Present Value (NPV) analysis and multi-criteria product selection. For individuals interested in business data communications, telecommunications, and an introduction to networking.