Wendell Odom, CCIE No. 1624 Emeritus, has been in the networking industry since 1981. He has worked as a network engineer, consultant, systems engineer, instructor, and course developer; he currently works writing and creating certification study tools. This book is his 28th edition of some product for Pearson, and he is the author of all editions of the CCNA Cert Guides about Routing and Switching from Cisco Press. He has written books about topics from networking basics, certification guides throughout the years for CCENT, CCNA R&S, CCNA DC, CCNP ROUTE, CCNP QoS, and CCIE R&S. He maintains study tools, links to his blogs, and other resources at www.certskills.com.