In Interconnecting Cisco Network Devices, Part 2 (ICND2), you will study actual router and switch output to aid your understanding of how to configure these devices. Many notes, tips, and cautions are also spread throughout the book. Specific topics include constructing medium-size routed and switched networks, OSPF and EIGRP implementation, access control lists (ACL), address space management, and LAN extensions into a WAN. Chapter-ending review questions illustrate and help solidify the concepts presented in the book. Whether you are preparing for CCNA certification or simply want to gain a better understanding of how to build medium-size Cisco networks, you will benefit from the foundation information presented in this book. Interconnecting Cisco Network Devices, Part 2 (ICND2), is part of a recommended learning path from Cisco that includes simulation and hands-on training from authorized Cisco Learning Partners and self-study products from Cisco Press. To find out more about instructor-led training, e-learning, and hands-on instruction offered by authorized Cisco Learning Partners worldwide, please visit www.cisco.com/go/authorizedtraining. Steve McQuerry, CCIE No. 6108, is a consulting systems engineer with Cisco focused on data center architecture. Steve works with enterprise customers in the Midwestern United States to help them plan their data center architectures. He has been an active member of the internetworking community since 1991 and has held multiple certifications from Novell, Microsoft, and Cisco. Before joining Cisco Steve worked as an independent contractor with Global Knowledge, where he taught and developed coursework around Cisco technologies and certifications.