In this section we would introduces the concepts and modes of Layer 2 Switching and physical-layer connectivity between switches. We will also introduce the Spanning Tree Protocol and its importance to switched systems.

In this section we would cover following CCNA objectives

• Use the CLI to discover neighbors on a network
• Manage switch startup and configuration
• Manage Cisco IOS images, configuration files, and devices on the network
• Describe how and when to implement and verify VLANs and trunking, and then implement them on the network
• Describe situations in which a spanning tree is used, and implement it on the network
• Describe the application and configuration of inter-VLAN routing for a medium-sized routed network
• Describe situations in which security is required at Layer 2, and implement it on the network
• Identify an approach for troubleshooting and isolating common switched network problems, and offer solutions