This book has been the market leader for engineers and systems designers due to its technical accuracy and cutting-edge orientation. The tenth edition is now updated to reflect changes in technologies and changes in the relative importance of these technologies. Older protocols have been replaced since TCP/IP and Ethernet are standard. The chapter on wireless technologies has been substantially revised and the importance of security includes the latest information on security design and new technologies. Engineers and systems designers will also find more hands-on activities and exercises so they can quickly develop an understanding of the technologies used for data communications.