Summary

This chapter covered many introductory concepts of Cisco's switches and how you use them in your network. AVVID is one of the core building blocks that Cisco uses when creating a network design. AVVID includes three components: Network Infrastructure, Intelligent Network Services, and Network Solutions.

Cisco uses a basic three-layer hierarchical model to describe the design process: core, distribution, and access. The core layer provides high-speed switching between distribution layers. The distribution layer provides Layer 3 services and separation of access and other distribution layers. The access layer provides a user's initial connection to the network.

Cisco expands on this model when designing campus networks. A campus network is made up of modules: Enterprise Campus (the campus itself), Enterprise Edge (buffer between remote sites), and Service Provider Edge (solutions for remote access). Within the Enterprise Campus are sub-modules, including Building Access, Building Distribution, Campus Core, and Server Farm. Layer 2 switches are used in the Building Access sub-module, either Layer 3 or multilayer switches are used in the Building Distribution sub-module, and either Layer 2 or Layer 3 switches are used in the Campus Core sub-modules.

There are three types of operating system modes for Catalyst switches: CatOS, hybrid, and native. CatOS mode provides only Layer 2 functionality for Supervisor Engines. Hybrid mode handles the Layer 3 cards installed in a CatOS switch. Native (IOS) mode handles both Layer 2 and Layer 3 processes in a Catalyst switch. The Switch Fabric Module (SFM) expands the backplane capacity of a 6500 switch from 32Gbps to 256Gbps.