Cisco CCNA 2 User manual

This document is exclusive property of Cisco Systems, Inc. Permission is granted to print and copy
this document for noncommercial distribution and exclusive use by instructors in the CCNA 2:
Routers and Routing Basics course as part of an official Cisco Networking Academy Program.

1 - 238 CCNA 2: Routers and Routing Basics v3.1 Instructor Guide – Welcome Copyright ©2004, Cisco Systems, Inc.
I.Welcome
Welcome to the CCNA 2 version 3.1 Instructor Guide. Cisco Worldwide Education (WWE) has
developed this guide to provide a helpful resource for instructors. This introduction will
emphasize four themes:
• Student-centered, instructor-facilitated model
• One size does not fit all
• Hands-on, skills-based learning
• Global community of educators
Student-Centered, Instructor-Facilitated
The CCNA curriculum has not been designed as a standalone e-learning or distance-learning
course. The teaching and learning model of the Cisco Networking Academy® Program is
based on instructor facilitation. The Learner Model: Academy Student diagram shows the
emphasis that WWE puts on the learner. The model begins with the prior knowledge of
students. The instructor guides learning events, which are built from a variety of resources, to
help the students achieve their desired comprehension of networking.

2 - 238 CCNA 2 Routers and Routing Basics v3.1 Instructor Guide – Welcome Copyright ©2004, Cisco Systems, Inc.
One Size Does Not Fit All
The Cisco Networking Academy Program serves hundreds of thousands of students in almost
150 countries. Students range from early teens to mature adults and from advanced middle
school students to undergraduate engineering students.
One curriculum cannot fit the needs of all students. WWE relies on local instructors to make
the program work and to help their students achieve the learning goals of the program. There
are three fixed reference points for each program that provide flexibility for the instructors:
• The mission of WWE to educate and train
• The requirements of the CCNA certification exam
• The hands-on skills that help prepare students for the industry and further
education
The WWE policy allows instructors to "add anything, but subtract nothing" from the curriculum.
WWE supports in-class differentiation, which is used to provide additional support for students
who need it and additional challenges for advanced students. WWE also allows instructors to
decide how much time to spend on various topics. Some topics can be skimmed, while others
may need to be emphasized for different audiences. The local instructor must decide how to
balance the need for hands-on labs with the realities of the local student-to-equipment ratio
and time schedule. This Guide can be used to facilitate the preparation of lesson plans and
presentations. Instructors are encouraged to research and use external sources to develop
additional labs and exercises.
Core TIs have been highlighted for emphasis to assist the instructor in course and lesson
planning. These are not the only TIs that need to be taught. Many core TIs will only make
sense after the preceding TIs have been reviewed. It may be useful to have a map of the core
TIs, which contain the most important knowledge and skills for success in the CCNA program.
The assessment process is multifaceted and flexible. A wide variety of assessment options
exist to provide feedback to students and document their learning. The Academy assessment
model is a blend of formative and summative assessments that include online and hands-on,
skills-based exams.
Hands-On, Skills-Based
The core of the CCNA 2 experience is the sequence of hands-on labs. Labs are designated as
either essential or optional. Essential labs include information that is fundamental to the CCNA
Academy student experience. This information will help students prepare for the certification
exam, succeed in job situations, and develop their cognitive abilities. In CCNA 2, students will
learn about the following elements of basic router configuration:
• Hostnames, banners, and passwords
• Interface configuration
• IOS file system
• Static routes and dynamic routing (RIP version 1 and IGRP)

3 - 238 CCNA 2 Routers and Routing Basics v3.1 Instructor Guide – Welcome Copyright ©2004, Cisco Systems, Inc.
• Standard and extended access-list configuration and placement
• show, debug, ping, trace, and telnet commands to verify and troubleshoot
Global Community
WWE instructors are members of a global community of educators. There are over 10,000
instructors that teach the same eight CCNA and CCNP courses in the program. Instructors
should take advantage of the diversity and skills of this community through their Regional
Academies, Cisco Academy Training Centers (CATCs), the Cisco Academy Connection
(CAC), or through other forums. WWE is committed to the improvement of the curriculum,
assessment model, and instructional resources such as this guide. Please submit any
feedback through CAC. Check CAC for new releases of instructional materials.
Guide Overview:
Section II provides a scope and sequence overview of the course. Section III summarizes the
most important learning objectives, target indicators, and labs, and offers teaching suggestions
and background information. Section IV provides a case study related to network design,
implementation, and troubleshooting. Instructors can also devise their own case studies.
Section V includes four appendices:
• Cisco online tools and utilities
• CCNA assessment guidelines
• Evidence-centered design of assessment tasks in the Networking Academy
program
• Instructional best practices

4 - 238 CCNA 2: Routers and Routing Basics v3.1 Instructor Guide – Course Overview Copyright ©2004, Cisco Systems, Inc.
II. Course Overview
Target Audience
The target audience is anyone who desires a practical and technical introduction to the field of
networking. This includes high school, community college, and lifelong-learning students who
are interested in careers as network technicians, network engineers, network administrators,
and network help-desk staff.
Prerequisites
The successful completion of this course requires the following:
• Reading age level of 13 or higher
• Successful completion of CCNA 1
The following prerequisites are beneficial, but not required:
• Prior experience with computer hardware and command line interfaces
• Background in computer programming
Course Description
CCNA 2: Routers and Routing Basics is the second of four CCNA courses that lead to the
Cisco Certified Network Associate (CCNA) designation. CCNA 2 focuses on initial router
configuration, Cisco IOS Software management, routing protocol configuration, TCP/IP, and
access control lists (ACLs). Students will learn how to configure a router, manage Cisco IOS
software, configure routing protocols on routers, and set access lists to control access to
routers.
Course Objectives
The CCNA certification indicates knowledge of networking for the small office, home office
(SOHO) market and the ability to work in small businesses or organizations that use networks
with fewer than 100 nodes. A CCNA-certified individual can perform the following tasks:
• Install and configure Cisco switches and routers in multiprotocol internetworks that
use LAN and WAN interfaces
• Provide Level 1 troubleshooting service
• Improve network performance and security
• Perform entry-level tasks in the planning, design, installation, operation, and
troubleshooting of Ethernet and TCP/IP Networks

5 - 238 CCNA 2: Routers and Routing Basics v3.1 Instructor Guide – Course Overview Copyright ©2004, Cisco Systems, Inc.
Students must successfully complete the CCNA 2 course before they can achieve CCNA
certification.
Upon completion of this course, students will be able to perform tasks related to the following:
• Routers and their roles in WANs
• Cisco IOS Software Management
• Router configuration
• Router file management
• RIP and IGRP routing protocols
• TCP/IP error and control messages
• Router troubleshooting
• Intermediate TCP
• Access control lists
Lab Requirements
Please refer to the CCNA equipment bundle spreadsheets on the Cisco Academy Connection.
Certification Alignment
The curriculum is aligned with the following Cisco Internet Learning Solution Group (ILSG)
courses:
• CCNA (Cisco Certified Network Associate)
• INTRO (Introduction to Cisco Networking Technologies)
The Course 2 claims state that students will be able to complete the following tasks:
• Identify the key characteristics of common wide-area network (WAN)
configurations and technologies, and differentiate between these and common
LAN technologies
• Describe the role of a router in a WAN
• Describe the purpose and operations of the router Internet Operating System
(IOS)
• Establish communication between a terminal device and the router IOS, and use
IOS for system analysis, configuration, and repair
• Identify the major internal and external components of a router, and describe the
associated functionality

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• Connect router Fast Ethernet, serial WAN, and console ports
• Perform, save, and test an initial configuration on a router
• Configure additional administrative functionality on a router
• Use embedded data-link layer functionality to perform network neighbor discovery
and analysis from the router console
• Use embedded Layer 3 through Layer 7 protocols to establish, test, suspend, or
disconnect connectivity to remote devices from the router console
• Identify the stages of the router boot-up sequence and show how the configuration
register and boot system commands modify that sequence
• Manage system image and device configuration files
• Describe the operation of the Internet Control Message Protocol (ICMP) and
identify the reasons, types, and format of associated error and control messages
• Identify, configure, and verify the use of static and default routes
• Evaluate the characteristics of routing protocols
• Identify, analyze, and show how to rectify inherent problems associated with
distance vector routing protocols
• Configure, verify, analyze, and troubleshoot simple distance vector routing
protocols
• Use commands incorporated within IOS to analyze and rectify network problems
• Describe the operation of the major transport layer protocols and the interaction
and carriage of application layer data
• Identify the application of packet control through the use of various access control
lists
• Analyze, configure, implement, verify, and rectify access control lists within a
router configuration
Course Overview
The course has been designed for 70 contact hours. Approximately 35 hours will be
designated to lab activities and 35 hours will be designated to curriculum content. A case
study on routing is required. The format and timing should be determined by the Local
Academy.

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The following changes have taken place since CCNA version 2.x:
• More emphasis on router configuration early in semester
• More efficient presentation and practice of IOS
• IGRP moved from CCNA 3 to CCNA 2
• Access lists moved from CCNA 3 to CCNA 2
• Revisions to TCP/IP coverage
• More focus on routing tables
• Case study is required with format and timing determined by the Local Academy
• More interactive flash activities
• Sequence of over 40 e-Labs
• Lab focus on two-router labs

8 - 238 CCNA 2: Routers and Routing Basics v3.1 Instructor Guide – Teaching Guide: TI by TI Copyright ©2004, Cisco Systems, Inc.
III. Teaching Guide for Each TI
Nomenclature
The CCNA curriculum uses the following hierarchy:
• Course
• Module
• Learning objective (LO)
• Target indicator (TI)
For example, 3.2.5 references Module 3, LO 2, and TI 5. The following terms are commonly
used to describe the curriculum, instructional materials, and assessments in WWE and Cisco
documentation:
• Certification-level claims
High-level statements about what a CCNA-certified person should know and be
able to do. These claims are measured through certification exams.
• Course
A subset of a curriculum which is a collection of chapters to be offered as a
scheduled course.
• Course-level claims
Medium-level statements about what a person who completes the CCNA 2 course
should know and be able to do.
• Core TI
The TIs that apply most directly to the claims and learning objectives. Instructors
should not skip over these TIs or move through them quickly.
• Curriculum
A predefined or dynamic path of learning events with an end goal such as
certification or the acquisition of required job skills and knowledge.
• Hands-on skills
There is some overlap between hands-on skills and claims. These statements
emphasize hands-on, lab-based learning.

9 - 238 CCNA 2: Routers and Routing Basics v3.1 Instructor Guide – Teaching Guide: TI by TI Copyright ©2004, Cisco Systems, Inc.
• Module
Logical groupings that comprise a course. Modules contain multiple lessons or
LOs. Modules are also referred to as chapters.
• Learning objective (LO)
A statement that establishes a measurable behavioral outcome. LOs are used to
organize content and to indicate how the acquisition of skills and knowledge will be
measured. LOs are also referred to as terminal objectives or RLOs.
• Lesson
A set of TIs, or enabling objectives, that are grouped together and presented in a
coherent format to meet an LO, or terminal objective. Lessons emphasize the role
of the instructor. Learning objectives emphasize the role of the students.
• Module caution
Suggestions related to areas where difficulties may be encountered. These are
especially important for syllabus development, lesson planning, and pacing.
• Optional lab
A lab that is for practice, enrichment, or differentiation.
• Essential lab
A lab that is fundamental to the course.
• Reusable Learning Object (RLO)
This is a Cisco Instructional Design term. RLOs typically consist of five to nine
RIOs. In this guide, RLOs are equivalent to lessons or learning objectives.
• Reusable Information Object (RIO)
This is a Cisco Instructional Design term. In this guide, RIOs are equivalent to
target indicators.
• Target indicator (TI)
TIs are also referred to as enabling objectives or RIOs. TIs typically consist of a
text frame with graphics and several media content items.

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Module 1: WANs and Routers
Overview
When teaching Module 1, show the students how router configuration relates to the Internet,
which is a global internetwork made possible by routers. Students will learn the difference
between WANs and LANs, and will identify WAN connections, encapsulations, and protocols.
Module 1 Caution
WANs will be taught in detail in CCNA 4. In CCNA 2, it is important to teach students the
fundamental basics of WANs and roles that routers play in the WAN connection. Inform the
students that the serial interfaces will be used to simulate the DCE to DTE WAN connection.
Do not spend too much time on this module.
Students who complete this module should be able to:
• Identify organizations responsible for WAN standards
• Explain the difference between WANs and LANs and the types of addresses they
use
• Describe the role of a router in a WAN
• Identify internal components of a router and describe their functions
• Describe the physical characteristics of a router
• Identify common ports on a router
• Connect Ethernet, serial WAN, and console ports

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1.1 WANs
Essential labs: None
Optional labs: None
Core TIs: All
Optional TIs: none
Course-level claim: Students can identify the important characteristics of common WAN
configurations and technologies, differentiate between these and common LAN technologies,
and describe the role of a router in a WAN.
Certification-level claim: Students can evaluate the important characteristics of WANs and
implement simple WAN protocols.
Hands-on skills: none
1.1.1 Introduction to WANs
WANs differ from LANs in several ways:
• LANs connect workstations, peripherals, terminals, and other devices in a single
building or several buildings that are located next to each other, and WANs
connect large geographic areas.
• LANs connect devices and WANs connect data connections across a broad
geographic area.
WANs operate at the physical and data-link layers of the OSI model. Devices used in a WAN
are routers, switches, modems, and communication servers. The following topics are relevant
to this TI:
• Discuss the various carriers and devices available for WAN connections.
• Show students what routers in a WAN look like.
• Explain what routers do.
Figure 3 is an important figure to review. Best instructional practices for this TI include online
study sessions with study guides, group work, and mini-lectures. This TI provides essential
background information for the CCNA exam.
1.1.2 Introduction to routers in a WAN
Routers and computers have four basic common components:
• CPU
• Bus

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• Memory
• Interfaces
However, the main purpose of a router is to route, not to compute. The main components of
the router are as follows:
• RAM
• NVRAM
• Flash
• ROM
• Interfaces
The following topics should be covered in this TI:
• Discuss the similarities of computers and routers such as the software they use.
• Explain the components of the router and what each component contains.
• Open a router and let the students examine the inside. Point out the main
components.
• Explain that just as a computer cannot work without an operating system and
software, a router cannot work without an operating system and configurations.
1.1.3 Router LANs and WANs
Routers function in both LANs and WANs. They are primarily used in WANs. Explain that
routers have both LAN and WAN interfaces. Students should be able to identify the
differences. The two main functions of a router are to select the best path and to forward
packets to the correct outgoing interfaces.
Networking models are useful because they facilitate modularity, flexibility, and adaptability.
Like the OSI model, the three-layer design model is an abstract picture of a network. Models
may be difficult to comprehend because the exact composition of each layer varies from
network to network.
Explain that each layer of a three-layer design model may include a router, a switch, a link, or
some combination of these. Some networks may combine the function of two layers into a
single device or may omit a layer entirely. The three-layer design model consists of the
following:
• The core layer forwards packets as quickly as possible.
• The distribution layer provides a boundary by using filters to limit what gets to the
core.
• The access layer feeds traffic into the network and controls entry into the network.

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1.1.4 Role of Routers in a WAN
There are several encapsulations associated with serial lines:
• HDLC
• Frame Relay
• PPP
• SDLC
• SLIP
• LAPB
Some of the most common WAN technologies are as follows:
• POTS
• ISDN
• X.25
• Frame Relay
• ATM
• T1, T3, E1, and E3
• DSL
• SONET
Ask students to briefly explain each of the WAN technologies and discuss the differences
between technologies and encapsulations. They will be covered in detail in CCNA 4.
It is important to encourage student interest and enthusiasm in this TI. The world of WAN
technologies is briefly introduced. Many students will be familiar with one or more of the
technologies used. Many of these topics will be covered in CCNA 4 and students should be
encouraged to do additional research on one of these technologies and present it to the class.
1.1.5 Academy approach to hands-on labs
In the Networking Academy lab, all the networks are connected with a serial or Ethernet cable.
This allows the students to see and touch all of the equipment. In a real network, the routers
would not be in one physical location. In the Networking Academy lab, the serial cables are
connected back-to-back. However, in the real world the cables would be connected through a
CSU or DCE device.
Discuss the differences between real networking environments and the router lab setup. Help
the students visualize the components between the V.35 connectors. If they can understand
this picture, then they will realize that they are working with a complete WAN minus the carrier
services.

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Each student should build a complete topology and then take it apart and let the next student
do the lab. These labs are a review of the cabling labs in CCNA 1. This may be one of the last
opportunities students have to cable a network, so do not miss this opportunity to make sure
students complete the CCNA 2 Lab setup. This is a good place to introduce troubleshooting
and the Layer 1 issues that occur in CCNA 2. It is also a fairly simple and fun activity.
1.2 Routers
Essential Labs: 1.2.5, 1.2.6, and 1.2.7
Optional Labs: None
Core TIs: All
Optional TIs: none
Course- Level Claim: Students can properly connect router Fast Ethernet, Serial WAN, and
console ports.
Certification-Level Claim: Students can describe the components of network devices. They
can also identify the major internal and external components of a router and describe the
associated functionality.
Hands-on skills: none
1.2.1 Introduction to WANs
This section overviews the physical aspect of a router. The physical layer is always studied
first in networking topics. The student will be able to identify internal components of the router
and describe their functions, describe the physical characteristics of the router, identify
common ports on a router, and properly connect FastEthernet, Serial WAN, and console ports.
The components in a router are essentially the same as those in a computer. In fact, a router
can be thought of as a computer designed for the special purpose of routing. While the exact
architecture of the router varies in different router series, this section will introduce the major
internal components. The figures show the internal components of some of the Cisco router
models.
Ask students the following questions:
• What are the common components of a router?
• What is NVRAM used for?
1.2.2 Router physical characteristics
It is not necessary to know the location of the physical components inside the router to
understand how to use the router. The exact components used and their locations vary in
different router models.

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Ask students the following questions:
• What are the different types of RAM used by a router?
• Can the RAM be upgraded in a router?
1.2.3 Router external connections
The three basic types of connections on a router are LAN interfaces, WAN interfaces, and
management ports. LAN interfaces allow the router segment network boundaries within a LAN
and reduce broadcast traffic within a LAN. WAN connections are provided through a service
provider which connects two or more distant site through the Internet or PSTN. The LAN and
WAN connections provide network connections through which frames are passed. The
management port provides an ASCII or text-based connection for the configuration and
troubleshooting of the router.
Ask students the following questions:
• What are the three basic types of connections on a router?
• What is the console connection used for?
1.2.4 Management port connections
The management ports are asynchronous serial ports. They are the console port and the
auxiliary port. Not all routers have an auxiliary port. These serial ports are not designed as
networking ports. To prepare for initial startup and configuration, attach an RS-232 ASCII
terminal or a computer that emulates an ACSII terminal to the system console port.
It is essential for students to understand the difference between network interfaces and non-
network interfaces. The instructor may need to talk about the differences extensively.
Discuss the following topics:
• The network ports use network encapsulation frames while the non-network ports
are bit and byte oriented.
• There is no addressing involved in the serial management ports.
• The serial interface for management is asynchronous and the serial WAN interface
is synchronous.
Ask students the following questions:
• Which port is preferred for troubleshooting and why?
• Do all routers have an auxiliary port?
1.2.5 Console Port Connections
The console port is a management port used to provide out-of-band access to a router. It is
used for the initial configuration of the router, monitoring, and disaster recovery procedures.

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Students may not be familiar with the term out-of-band. Out-of-band refers to the fact that the
management control communications use a different path or channel than the data
communications.
Ask students the following questions:
• What type of terminal emulation must the PC or terminal support?
• What are the steps to connect the PC to a router?
1.2.6 Connecting Router LAN interfaces
In most LAN environments, an Ethernet or FastEthernet interface is used to connect the router
to the LAN. The router is a host that connects to the LAN through a hub or a switch. A straight-
through cable is used to make this connection. The correct interface must be used.
If the wrong interface is connected, the router or other networking devices may be damaged.
This is generally not true within LAN interfaces. However, if LAN interfaces are connected to
some form of WAN interface such as ISDN, damage can occur. The students should be taught
to be observant and careful whenever connections are made.
Ask students the following questions:
• What type of cable is used to connect from the router Ethernet interface to a hub
or switch?
• What type of cable is used to connect from the router Ethernet interface to a router
Ethernet interface?
1.2.7 Connecting WAN interfaces
There are many forms of WAN connections. A WAN uses many different types of technology
to make data connections across a broad geographic area. WAN services are usually leased
from service providers. The WAN connection types include leased line, circuit switched, and
packet switched.
Many of the WAN interfaces use the same physical interfaces but different pinouts and
electrical characteristics. This difference in electrical characteristics could potentially cause
damage if the wrong connections were made. Again, the students should be taught to be
observant and careful when they make any connections.
Ask students to perform the following tasks:
• List the physical layer standards that Cisco routers support.
• List the different types of WAN connections.

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Module 1 Summary
Before students move on to Module 2, they must be able to cable the lab setup, identify all
external relevant ports, and identify internal router components.
Online assessment options include the end-of-module online quiz in the curriculum and the
online Module 1 exam. Consider introducing formative assessments, where the instructor
supervises the students as they work on the router setup. The use of formative assessments
can be very valuable while students work through this router-intensive and IOS-intensive
course.
Students should understand the following main points:
• WAN and LAN concepts
• Role of a router in WANs and LANs
• WAN protocols
• How to configure console connections
• The identification and description of the internal components of a router
• The physical characteristics of a router
• The common ports on a router
• How to connect router console, LAN, and WAN ports

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Module 2: Introduction to Routers
Overview
Consider the prior knowledge of students when teaching Module 2. Some students may be
familiar with command-line interfaces (CLIs). Students who have only used GUIs may not
know how to use CLIs to interact with a computer. Students should experiment with CLIs to
learn how to interact with a router.
Module 2 Caution
Students need to know what the IOS is and what it does. They also need to know the
difference between the configuration file and the IOS. It is also important for students to feel
comfortable when they enter into and move around in the CLI. Do not move too quickly
through these labs. If students are uncomfortable with the CLI, they will have difficulties with
more complex labs.
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
• Move between the user command 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

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2.1 Operating Cisco IOS Software
Essential Labs: None
Optional Labs: None
Core TIs: All
Optional TIs: none
Course-Level Claim: Students can describe the purpose and fundamental operation of the
router IOS.
Certification-Level Claim: Students can establish communication between a terminal device
and the router IOS and use it for system analysis, configuration, and repairs.
Hands-on skills: none
2.1.1 The purpose of Cisco IOS software
In this TI, students will be introduced to the fundamentals of the Cisco Internet Operating
System (IOS). Student will learn about the show version command, which helps users gain
information about the Cisco IOS. The IOS command line interface is introduced in another
lesson, so there is no need to focus on the show command in this TI.
A router and switch cannot function without an operating system. Cisco IOS is the installed
software in all Cisco routers and Catalyst switches.
A computer needs an operating system such as Windows or UNIX. Discuss how the hardware
cannot function without this software. Make sure the students understand the role of the IOS.
2.1.2 Router user interface
Cisco IOS software uses a command-line interface (CLI) as its console environment. The CLI
is accessible through several methods:
• Console port
• Auxiliary port
• Telnet session
Students should know the difference between these methods. They should also be
comfortable with the term CLI.
2.1.3 Router user interface modes
The user EXEC mode allows a limited number of basic monitoring commands. This mode is
often referred to as a view-only mode. The privileged EXEC mode provides access to all router
commands. To enter the privileged mode from user mode the enable command must be
entered. The privileged mode is used to access other modes to configure the router.