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CCNA 2: Routers and Routing Basics v3.1 Instructor Guide – Module 2
Copyright
©
2004, Cisco Systems, Inc.
Students should be able to identify the router prompts. The user mode prompt is
Router>
.
The privileged mode prompt is
Router#
.
2.1.4 Cisco IOS software features
Cisco IOS devices have three operating environments:
•
ROM monitor
•
Boot ROM
•
Cisco IOS
ROM monitor is used to recover from system failures and recover a lost password. Boot ROM
is used to modify the Cisco IOS image in flash. There is a limited subset of features in this
mode. Normal operation of a router requires the full Cisco IOS image. Discuss the three
operating environments. Students should be able to identify these environments.
Students
must be familiar with the IOS to control the router. Cisco technology is in the IOS, not in the
hardware.
2.1.5 Operation of Cisco IOS software
There are numerous IOS images for different Cisco device models. Each devise uses a similar
basic command structure for configuration. The configuration and troubleshooting skills
acquired on a specific device will apply to a variety of products.
The naming convention for the different Cisco IOS Releases contains three parts:
•
The platform on which the image runs
•
The special capabilities and feature sets supported in the image
•
Where the image runs and whether it has been zipped or compressed
One of the major constraints for the use of a new IOS image is compatibility with the router
flash and RAM memory.
The students should also understand that the same IOS is used on the smallest to the largest
Cisco products. This will assure students that the skills they develop on small Cisco routers
can be applied to larger routers and switches.
Show students various naming conventions and identify the three parts of the naming
convention. For example, in cpa25-cg-1, cpa25 is the Cisco Pro 2500 Router, cg is the feature
capability such as communication server, remote-access server, or ISDN, and the 1 is the run
location or compressed status.
Explain that it is important to install and maintain various IOS versions, especially newer
versions with advanced features. Encourage the students to conduct research online at
www.cisco.com for more information on how to obtain various IOS images.