Module 2: Introduction to Routers / Overview / The purpose of Cisco IOS software

Module 2: Introduction to Routers
Overview: Cisco technology is based on the Cisco IOS, which is the software that controls the routing and switching functions of network devices. A solid understanding of the IOS is essential for a network administrator. This module will introduce the main features of the IOS and will provide practice in working with the IOS. All network configuration tasks, from the most basic to the most complex, require a strong foundation in the basics of router configuration. This module will provide the tools and techniques for basic router configuration that will be used throughout this course.


This module covers some of the objectives for the CCNA 640-801, INTRO 640-821, and ICND 640-811 exams. -

Students who complete this module should be able to perform the following tasks:

• Describe the purpose of the IOS
• Describe the basic operation of the IOS
• Identify various IOS features
• Identify the methods to establish a command-line interface (CLI) session with the router
• Alternate between the user executive (EXEC) and privileged EXEC modes
• Establish a HyperTerminal session on a router
• Log into a router
• Use the help feature in the command line interface
• Troubleshoot command errors

The purpose of Cisco IOS software 
2.1.1 As with a computer, a router or switch cannot function without an operating system. This page will review the Cisco IOS. It is the embedded software architecture in all of the Cisco routers and is also the operating system of the Catalyst switches. Without an operating system, the hardware does not have any capabilities. The Cisco IOS provides the following network services:


• Basic routing and switching functions
• Reliable and secure access to networked resources
• Network scalability

The next page will discuss the Cisco IOS environment for a router.