The IOS User Interface

The Cisco Internetwork Operating System (IOS) is the kernel of Cisco routers and most switches. In case you didn’t know, a kernel is the basic, indispensable part of an operating system that allocates resources and manages things such as low-level hardware interfaces and security.

In the following sections, I’ll show you the Cisco IOS and how to configure a Cisco router using the command-line interface (CLI).


I’m going to save Cisco switch configurations for Chapter 10, “Layer 2 Switching and Spanning Tree Protocol (STP).”

Cisco Router IOS

The Cisco IOS is a proprietary kernel that provides routing, switching, internetworking, ...

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