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Cisco Internetwork Operating
System (IOS) Fundamentals
The CCNA exam requires that you understand the basics of the Cisco Internetwork
Operating System (IOS). In fact, the only operating system and user interface covered on
the CCNA exam is the IOS and its user interface. The omission of other user interfaces, in
particular the Catalyst 5000/5500 series user interface, is one of the most important facts to
note when determining what to study for the CCNA exam.
The IOS runs on some Cisco switch models and provides the familiar IOS command-line
interface (CLI). This chapter is geared toward the IOS CLI on a router. Chapter 4, "Bridges/
Switches and LAN Design," covers some details of IOS CLI on LAN switches. The user
interface is the same, but some commands are different.
The exam also includes questions on both router and LAN switch usage of the IOS. No one
should be surprised that the CCNA exam covers IOS running on routers. Also covered on
the exam is the use of IOS running on Cisco 1900 series switches. User interfaces on other
switch platforms might seem to be like IOS and have similar features, but these details are
not covered on the exam. That should be particularly helpful for those of you with less
hands-on experience.
Cisco requires that CCNAs exhibit a solid recollection of the many details of the CLI. Of
course, the best way to learn about any user interface is to use it. If you can spend time using
a Cisco router, the knowledge and recall you gain will be of significant value. This chapter
is designed to remind you of details you might not notice when practicing and will provide
a reference for those of you who do not have access to routers for practice. Still, there is no
substitute for hands-on practice.
How to Best Use This Chapter
By taking the following steps, you can make better use of your study time:
·
Keep your notes and the answers for all your work with this book in one place,
for easy reference.
·
Take the "Do I Know This Already?" quiz, and write down your answers. Studies
show that retention is significantly increased through writing down facts and
concepts, even if you never look at the information again.
·
Use the diagram in Figure 2-1 to guide you to the next step.
ch02.fm Page 21 Monday, March 20, 2000 4:57 PM