Cisco Systems Networking Academy Program: First-Year Companion Guide, Revised Edition is a companion and supplement to the first- and second-semesters of Cisco Systems Networking Academy Program classes. This book will support and reinforce the online training materials for the Cisco Systems Network Academy Program, along with topics pertaining to CCNA certification. The first-year guide provides an in-depth discussion of the OSI reference model layers and path determination, in addition to the configuration details for IP routing and addressing, subnetting topics, and basic router configuration and operation. The instructional materials for the First-Year Companion follows the instructional style and format that Cisco has created for the Cisco Networking Academy Program. Developed with and approved by Cisco Systems, Cisco Systems Networking Academy Program: First-Year Companion Guide, Revised Printing provides information and presentation unmatchable by any other publisher.