CCNA Certification All-in-One For Dummies E-Book

Silviu Angelescu

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 1183

Veröffentlichungsjahr: 2010

Beschreibung

A complete preparation guide for the entry-level networking CCNA certification If you're planning to advance your career by taking the all-important Cisco Certified Network Associate (CCNA), this is the study guide you need! Seven minibooks cover all the concepts and topics on which you'll be tested, covering the latest version of the exam. Each part of the exam is covered thoroughly in its own section, so you can readily find the information you want to study. Plenty of review questions help you prepare, and the companion CD-ROM includes the highly rated Dummies Test Engine so you can test your progress with questions based on exam content. * The Cisco Certified Network Associate (CCNA) is the entry-level certification for network professionals * Seven minibooks in this guide cover Secure Device Manager, Virtual Private Networks, IPv6, 2960 Switches, Cisco Network Assistant, Advanced EIGRP and OSPF, and Introduction to Wireless Networks * Covers the latest version of the exam, including the new voice, security and wireless components added in 2008 * Packed with review questions to help you prepare * Includes more security and troubleshooting information * CD-ROM includes the popular Dummies Test Engine, an exclusive, fully customizable test-prep software package that features twice as many sample questions as the previous version CCNA Certification All-In-One For Dummies is the preparation guide you need to earn your CCNA certification. Note: CD-ROM/DVD and other supplementary materials are not included as part of eBook file.

Leseprobe

CCNA® Certification All-in-One For Dummies®

Table of Contents

Introduction

About This Book

Foolish Assumptions

How This Book Is Organized

Icons Used in This Book

Where to Go from Here

Book I: Networking Basics

Book I: Chapter 1: Introducing Computer Networks

Purpose of Computer Networks

Network applications

Operation Flow of Computer Networks

Topologies of Computer Networks

Book I: Chapter 2: The OSI Reference Model

Introduction to the OSI Reference Model

Seven Layers

Layer 7: Application

Layer 6: Presentation

Layer 5: Session

Layer 4: Transport

Layer 3: Network

Layer 2: Data link

Layer 1: Physical

Benefits of the OSI Reference Model

Book I: Chapter 3: Introducing the TCP/IP Protocol Suite

Introduction to the TCP/IP Protocol Suite

Layer 7: Application

Some TCP/IP protocols at Layer 7

Some TCP/IP software applications at Layer 7

Layer 6: Presentation

Some TCP/IP protocols at Layer 6

Some TCP/IP software applications at Layer 6

Layer 5: Session

Layer 4: Transport

Connectionless transport

Connection-oriented transport

The most common TCP/IP protocols at Layer 4

TCP flow control

UDP simplicity

TCP/IP ports

Layer 3: Network

Some TCP/IP protocols at Layer 3

Hierarchy of IP addresses

Layer 2: Data Link

Some TCP/IP protocols at Layer 2

Address resolution

Layer 1: Physical

Book I: Chapter 4: Data Encapsulation

Introducing Data Encapsulation

Book I: Chapter 5: Binary, Hexadecimal, and Decimal Numbering Systems

Decimal Numbers

Binary Numbers

Hexadecimal Numbers

Numbering systems notation

Bits, nibbles, and bytes

Converting binary to hexadecimal

Converting hexadecimal to binary

Book I: Chapter 6: Local-Area Networks (LANs)

Introduction to Local-Area Networks

Ethernet Networking

CSMA/CD protocol

Duplex communication

Ethernet Standards

10-Mbps Ethernet (IEEE 802.3)

Fast Ethernet (100-Mbps)

Gigabit Ethernet (1000-Mbps)

10 Gigabit Ethernet (10000-Mbps)

Ethernet in the OSI Model

Data link layer

Physical layer

Book I: Chapter 7: Introducing Wide-Area Networks (WANs)

Introducing Wide-Area Networks

Dedicated Leased Line Connections

Advantages of leased lines

Disadvantage of leased lines

Dedicated leased line protocols

Circuit-Switched Connections

Advantage of circuit-switched connections

Disadvantages of circuit-switched connections

Circuit-switched connection protocols

Packet-Switched Connections

Advantages of packet-switched connections

Disadvantage of packet-switched connections

Packet-switched connection protocols

Cell-Switched Connections

Advantages of cell-switched connections

Disadvantages of cell-switched connections

Cell-switched connection protocols

Book I: Chapter 8: Introducing Wireless Networks

Wireless LAN (WLAN)

Wireless WAN

Benefits and Costs of Wireless Networks

Security Risks

Service set identifier (SSID)

Wired Equivalent Privacy (WEP)

Wi-Fi Protected Access (WPA)

MAC address filtering

Book I: Chapter 9: Network Design

Cisco Hierarchical Network Model

Core Layer

Highly available core

Distribution Layer

Access Layer

Benefits

Specialization

Scalability

Limitation of problem domain

Book I: Chapter 10: Introducing Cisco Hardware and Software

Introducing Cisco Products

Cisco software

Cisco hardware

Introducing Cisco Device Configurations

Startup configuration

Running configuration

Meet the Cisco IOS User Interface

Cisco IOS command-line interface (CLI)

Cisco IOS graphical user interface (GUI)

Book II: TCP/IP

Book II: Chapter 1: Introducing TCP/IP

TCP/IP communication

We pioneered this

Components of TCP/IP

Introducing the major TCP/IP layers and protocols

Demystifying data encapsulation

Book II: Chapter 2: TCP/IP Layers and Protocols

Information Exchange through the OSI Layer

OSI Layers and Protocols

The physical layer: Layer 1

The data link layer: Layer 2

The network layer: Layer 3

The transport layer: Layer 4

The session layer: Layer 5

The presentation layer: Layer 6

The application layer: Layer 7

TCP/IP Layers and Protocols

The network access layer: Layer 1

The Internet layer: Layer 2

The host-to-host transport layer: Layer 3

The application layer: Layer 4

Book II: Chapter 3: IP Addressing

The Purpose of IP Addresses — It’s All about the Delivery

The Hierarchy of IP Addresses — Who’s in Charge?

Network and host addressing

Classes of IP addresses

Other reserved addresses

Understanding network ID, host ID, and subnet masks

Private IP Addresses — We Reserve the Right . . .

Broadcasting — Shouting to the World!

Data-link Layer 2 broadcasts

Address Resolution Protocol — ARP’s on the Case, Sherlock!

The purpose of ARP

Proxy ARP

And what about RARP?

Book II: Chapter 4: Subnetting

Subnetting Basics

Purpose of subnetting

Subnet masks

Creating subnets

Subnet mask, network ID, host ID, and broadcast IP

Classless interdomain routing (CIDR)

IP Address Class and Subnet Mask

Class C IP address subnets

IP subnet zero

Host addressing assignments

Class B IP address subnets

Class A IP address subnets

Variable-Length Subnet Masks (VLSMs)

Purpose of VLSM

VLSM design guidelines

Optimizing IP addressing with VLSM

Summarization

Summarization investigated

Summarization and VLSM

Book II: Chapter 5: Internet Protocol Version 6 (IPv6)

Internet Protocol Version 6 (IPv6)

The Benefits of IPv6

Introducing IPv6 Addressing

IPv6 address notation

Configuring IPv6

Address autoconfiguration — DHCP who?

A dynamic approach

ICMPv6

Routing with IPv6

Static routing — Gimme some static!

Introducing IPv6 routing protocols

Migrating to IPv6

Migration methods

Book III: Switching with Cisco Switches

Book III: Chapter 1: Introducing Layer 2 Switches

Layer 2 — Data Link Layer Review

Purpose of a Layer 2 Switch

Hubs

Bridges

Switches

Basic Switch Functions

Address learning

Flooding, forwarding, and filtering frames

Avoiding loops

Managing Port Security

Filter based on MAC address

Filter based on number of devices connected

Filter based on sticky MAC address

Action triggered by filter

Transmitting Unicast, Multicast, and Broadcast

Book III: Chapter 2: Managing a Switch Using Cisco IOS

Best Practice for Using Cisco Switches

Connecting to a Cisco Switch

Connecting locally

Connecting remotely

Cisco Switch Startup Process

Configuring a Cisco Switch

Initial switch configuration

Managing Cisco switch configuration

Managing Cisco Switch Authentication

Console password

Telnet password

Auxiliary password

Privileged password

Encrypting passwords

Enabling Secure Shell (SSH)

Recovering switch passwords

Book III: Chapter 3: Controlling Network Traffic with Cisco Switches

Sending to MAC Addresses in Remote Networks

Sending frames within the LAN

Sending frames to a remote network

Deciding the Fate of Frames

Switching modes

Switching in Half-Duplex and Full-Duplex Modes

Reviewing half-duplex Ethernet

Reviewing full-duplex Ethernet

Duplex mode best practice

Configuring port duplex mode on a Cisco switch

Configuring port speed on a Cisco switch

Selecting a switch port

Avoiding Loops with Spanning Tree Protocol (STP)

Book III: Chapter 4: Spanning Tree Protocol (STP)

Introducing the Spanning Tree Protocol (STP)

STP Operation Flow

Electing a root bridge

Assigning STP port types

Achieving STP convergence

Introducing Cisco Options for STP

PortFast

BPDUGuard

BPDUFilter

UplinkFast

BackboneFast

Introducing Rapid Spanning Tree Protocol (RSTP)

Shorter delay before STP recalculation (max age timer)

Alternate port and backup port

Enabling RSTP on a Cisco switch

EtherChannel

EtherChannel and STP are friends

EtherChannel versions

Enabling EtherChannel on SW2 and SW5

Monitoring STP

Monitoring switch STP configuration

Monitoring port STP configuration

Book III: Chapter 5: Virtual Local Area Networks (VLANs)

Introducing Virtual Local Area Networks (VLANs)

VLANs keep things tidy

VLANs subdivide the broadcast domain

Benefits of VLANs

Managing VLANs

Create VLANs

Special-purpose VLANs

Static and dynamic VLAN membership

Identifying VLANs

Tagging data-link frames with a VLAN ID

VLAN Trunking

EtherChannel and VLANs are friends

VLAN or EtherChannel trunking? Both?

Configuring EtherChannel and VLAN trunking

Introducing switch port types

Managing VLAN trunk ports

VLAN Trunking Protocol (VTP)

VTP creates and manages VLANs

VTP does not manage VLAN port membership

VTP benefits

VTP domain

VTP server

VTP switch operating mode

VTP updates

VTP pruning

VLAN ID range

VTP requirements

Enabling VTP

Monitoring and troubleshooting VTP

Routing Traffic from One VLAN to Another

One router per VLAN

One large router with one port per VLAN

One subinterface per VLAN (router-on-a-stick)

Network (Layer 3) switch

Book III: Chapter 6: Voice over IP (VoIP)

Introducing Voice over IP (VoIP)

VoIP Requires Quality of Service (QoS)

Class of service (CoS) (IEEE 802.1p)

Cisco IP Phone

Cisco Discovery Protocol (CDP)

Negotiating VLAN

Negotiating CoS

Negotiating Cisco IP phone PC port

Configuring VoIP on Cisco Switches

Enabling QoS on the upstream switch

Configuring switch access port to trust CoS

Enabling VoIP VLAN on the switch access port

Book III: Chapter 7: Troubleshooting a Switch Using Cisco IOS

Troubleshooting Cisco Switches

Gathering information about the switch

Troubleshooting switch connectivity

Gather information about your network

Troubleshooting the startup configuration

Troubleshooting the running configuration

Book IV: Routing with Cisco Routers

Book IV: Chapter 1: Introducing Layer 3 Routers

Layer 3 — Network Layer Review

Purpose of a Layer 3 Router

Basic Router Functions

Managing routing protocols

Building routing tables

Routing packets

Book IV: Chapter 2: Managing a Router Using Cisco IOS

Best Practices for Using Cisco Routers

Connecting to a Cisco Router

Connecting locally

Connecting remotely

Cisco Router Startup Process

Configuring a Cisco Router

Initial router configuration

Managing Cisco router configuration

Managing Cisco Router Authentication

Console password

Telnet password

Auxiliary password

Privileged password

Encrypting passwords

Enabling Secure Shell (SSH)

Recovering router passwords

Book IV: Chapter 3: Network Routing

Introducing Network Routes

Static routes

Default routes

Dynamic routes

Routing Protocols

Routed Protocols

Routing Decision Criteria

Administrative distance

Routing protocol metrics

Routing Methods

Distance vector routing

Link-state routing

Hybrid routing

Configuring Routing Protocols

Book IV: Chapter 4: Routing Information Protocol (RIP)

Introducing Routing Information Protocol (RIP)

An interior gateway protocol

Routing tables, updates, and hop count

Routing error mitigation methods

Split horizon

Convergence and timers

RIPv1

RIPv2

RIPng

Configuring RIP

Verifying RIP

Book IV: Chapter 5: Enhanced Interior Gateway Routing Protocol (EIGRP)

IGRP — The Foundation of EIGRP

EIGRP Benefits

Characteristics of EIGRP

EIGRP Operation

Basic components

Routing tables

Neighboring successors

EIGRP packet types

Convergence

Route updates

DUAL — Diffusing Update Algorithm

Classful and classless routing

Configuring EIGRP

Start up EIGRP

Enable EIGRP on router interfaces

Verifying and Monitoring EIGRP Operation

Inspect the routing table

Inspect EIGRP protocol configuration

Inspect EIGRP topology table configuration

Inspect EIGRP neighbor information

Troubleshooting EIGRP

Book IV: Chapter 6: Open Shortest Path First (OSPF) Protocol

Introducing Open Shortest Path First (OSPF)

Routing tables

Characteristics of OSPF

Convergence

Route updates

Cost metric

OSPF Routing Hierarchy

OSPF route summarization

OSPF designated router (DR)

OSPF backup designated router (BDR)

Configuring OSPF

Start up OSPF

Enable OSPF on router interfaces

Configure OSPF options

Verifying and Monitoring OSPF Operation

Inspect the routing table

Inspect the OSPF protocol configuration

Inspect the OSPF interface configuration

Inspect the OSPF neighbor information

Inspect the OSPF routing database

Troubleshooting OSPF

Book V: Wireless Networks

Book V: Chapter 1: Introducing Wireless Networks

Purpose of Wireless Networks

Going over the Air, Locally or Globally

Wireless personal-area network (WPAN)

Wireless local-area network (WLAN)

Wireless metropolitan-area network (WMAN)

Wireless wide-area network (WWAN)

Sharing the Airwaves

Using unlicensed radio bands

Modulating the Airwaves

Introducing signals

Modulating signals

Using RF channels

Introducing RF modulation techniques

Introducing Wireless Local Area Network (WLAN) Standards (IEEE 802.11)

2.4-GHz band

5-GHz band

2.4-GHz and 5-GHz bands

Book V: Chapter 2: Wireless Local Area Network (WLAN) Security

Recognizing Security Risks

Introducing Security Risk Mitigation Methods

Authentication and data encryption

MAC address filtering

Hiding the service set identifier (SSID)

Intrusion detection and intrusion prevention

Changing default passwords

Management access

Book V: Chapter 3: Wireless Local Area Network (WLAN) Operation Modes

Ad Hoc Mode

Infrastructure Mode

Autonomous mode

Lightweight mode

Service set

Basic service set (BSS)

Extended service set (ESS)

Network planning and layout

Book V: Chapter 4: Managing Cisco Wireless Local Area Networks

Introducing the Cisco Unified Wireless Network Architecture (CUWN)

Cisco Wireless LAN Controller

Cisco WLAN Access Point (AP) Devices

Cisco Wireless Control System (WCS)

Lightweight Access Point Protocol (LWAPP)

Adaptive Wireless Path Protocol (AWPP)

Book V: Chapter 5: Configuring Cisco Wireless Local Area Networks

Configuration Flow

Set up and verify the wired LAN to which the WLAN will connect

Set up the Cisco Wireless LAN Controller(s)

Configure WLAN security

Set up Cisco access point(s)

Configuring backup controllers

Web authentication process

Example using the Cisco graphical user interface (GUI)

Book VI: Network Security

Book VI: Chapter 1: Network Security Basics

Network Zoning

Recognizing Security Risks

Information collectors

Introducing Security Risk Mitigation Methods

IP access control lists (ACLs)

NAT — The great masquerader

Virtual Private Networks (VPNs)

Cisco IOS Firewall

Cisco IOS Firewall — A sample configuration

Book VI: Chapter 2: Introducing IP Access Lists (IP ACLs)

The Purpose of Access Lists

Types of ACLs

Managing ACLs — Best Practices

Creating ACLs

Wildcard IP masks

Creating and applying the ACL

Creating standard ACLs

Creating extended ACLs

Creating Telnet/SSH ACLs

Creating named ACLs

Creating time-oriented ACLs

Creating switch port ACLs

Managing, Verifying, and Troubleshooting ACLs

Logging ACL IP matches

Configuring firewalls and ACLs with Cisco SDM GUI

Book VI: Chapter 3: Introducing Network Address Translation (NAT)

Purpose of NAT

Types of Network Address Translation

Local and global addresses

Operational Flow of NAT

Static NAT

Dynamic NAT operation

How overloading (PAT) operates

Configuring NAT

Configuring static NAT

Configuring dynamic NAT

Configuring Port Address Translation (PAT)

Managing NAT

Monitoring and troubleshooting NAT

Using the CLI commands

Configuring NAT with the Cisco SDM GUI

Book VI: Chapter 4: Introducing Virtual Private Networks (VPNs)

Purpose of VPNs

Type of VPNs

Choosing a VPN Implementation Method

Using IPsec

Using Secure Socket Layer (SSL)

Using tunneling

Split tunneling

Creating and Managing IPsec VPNs

Introducing IPsec protocols

Choosing transport mode versus tunnel mode

Configuring Cisco Virtual Private Networks

Creating a VPN with the Cisco Security Device Manager (SDM)

Enabling quality of service (QoS) in the VPN using Cisco SDM

Book VII: Wide Area Networks (WAN)

Book VII: Chapter 1: Wide-Area Networking Basics

Introducing WANs

Purpose of WANs

Data terminal equipment (DTE) and data communications equipment (DCE)

Cisco serial interfaces

DCE serial interfaces

Connection Types

Encapsulation Types

HDLC (High-Level Data Link Control)

PPP (Point-to-Point Protocol)

SLIP (Serial Line Internet Protocol)

Frame Relay

ATM (Asynchronous Transfer Mode)

X.25

Introducing Cable Connections

RJ-45 cabling

DB-25 cabling and adapters

Introducing Digital Subscriber Line (DSL) Connections

Book VII: Chapter 2: HDLC (High-Level Data Link Control) Protocol

Introducing the High-Level Data Link Control Protocol

HDLC links

Data framing

SLARP

Configuring HDLC

Monitoring HDLC

Book VII: Chapter 3: PPP (Point-to-Point Protocol)

What Is PPP?

Operational Flow of PPP

Link Control Protocol (LCP)

Purpose of LCP

LCP options

Network Control Protocol (NCP)

PAP and CHAP Authentication

Password Authentication Protocol (PAP)

Challenge Handshake Authentication Protocol (CHAP)

Configuring PPP

Set up router host names used for authentication

Configure passwords to authenticate between routers

Configure PPP encapsulation on the router interface

Configure PAP and CHAP authentication on both routers

Configuring PPP callback for ISDN Dial on Demand Routing (DDR)

Configuring PPP with the Cisco Security Device Manager (SDM)

Monitoring and Troubleshooting PPP

PPP link quality monitoring

PPP debug commands

Book VII: Chapter 4: Frame Relay

Introducing Frame Relay

Purpose of Frame Relay WAN connections

Establishing virtual circuits

Identifying virtual circuits using data-link connection identifiers (DLCIs)

Reserving bandwidth using access rate and CIR guarantee

Frame Relay link status control using LMI

Frame Relay frame structure

Frame Relay flow and congestion control using DE, FECN, and BECN

Frame Relay address resolution using Inverse ARP

Managing Frame Relay

Frame Relay topologies

Operational flow of Frame Relay

Split horizon issues in a Frame Relay WAN

Configuring single interfaces for Frame Relay over a point-to-point link

Configuring subinterfaces for Frame Relay over multipoint links

Configuring Frame Relay with the Cisco Router and Security Device Manager (SDM)

Monitoring and Troubleshooting Frame Relay

Book VII: Appendix A: About the CD

Prep Test

Book VII: Appendix B: Cisco CCNA Exam Preparation

Arriving at the exam location

Taking the exam

CCNA® Certification All-in-One For Dummies®

by Silviu Angelescu

CCNA® Certification All-in-One For Dummies®

Published byWiley Publishing, Inc.111 River StreetHoboken, NJ 07030-5774www.wiley.com

Copyright © 2010 by Wiley Publishing, Inc., Indianapolis, Indiana

Published simultaneously in Canada

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About the Authors

Silviu Angelescu is a network and software engineer, consultant and technical trainer, specialized in data networks, storage networks and virtualization. He has worked as network and software engineer, consultant and corporate trainer for more than ten years at various high-tech companies and academic institutions, such as, Network Appliance (NetApp), Computer Associates (CA), CGI, Dawson College, and the University of Montreal. Silviu also ran a consulting business for training organizations, designing, developing, and deploying scheduling software and network services. He graduated in Computer Science at the University of Montreal and is currently an engineer and trainer in the Research Triangle Park, in North Carolina, USA.

Andrew Swerczek is a network engineer, computer lab instructor, and technical writer with over twenty years experience in the Information Technology field. He has worked for various governmental agencies and contractors including the US Department of Defense and Wang Laboratories. Andrew has achieved many IT industry certifications such as CCNA, CNE, CNA, CIW, DCSNP, NACA, FCA, IBA, i-Net+, Network+, Server+, and A+. He is a graduate from the London School of Journalism, owns a small business, and currently resides in the Harz Mountains region, in Germany.

Author’s Acknowledgments

I would like to thank Katie Feltman, Pat O’Brien, John Edwards, and Bruce Tomlin: thanks for your hard work, support and patience. A lot of work goes into publishing and producing a book: I want to thank everyone at Wiley who worked behind the scenes to keep this project on track and make it happen.

I also want to thank Andrew Swerczek for his hard work and contribution to this book: Chapters one to five in Book II, Chapters one to four in Book VI, Chapters one to four in Book VII. Thanks also to Ed Tetz for his contribution: Chapters two to five in Book V.

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Introduction

The CCNA certification will serve as a basic foundation for a number of other certifications that you may pursue. The exam tests your knowledge of CCNA hardware and software used in today’s computer world, and the certification is one of the most popular certifications for IT professionals to prove their hardware and software knowledge.

About This Book

This book is designed to be a hands-on, practical guide to help you pass the CCNA exam. This book is written in a way that helps you understand complex technical content and prepares you to apply that knowledge to real-world scenarios.

I understand the value of a book that covers the points needed to pass the CCNA exams, but I also understand the value of ensuring that the information helps you perform IT-related tasks when you are on the job. That is what this book offers you — key points to pass the exams combined with practical information to help you in the real world, which means that this book can be used in more than one way:

♦ An exam preparation tool: Because my goal is to help you pass the CCNA exams, this book is packed with exam-specific information. You should understand everything that is in this book before taking the exams.

♦ A reference: Rely on my extensive experience in the IT industry not only to study for (and pass) the exams but also to help you perform common computer-related tasks on the job. I hope you find this book a useful tool that you can refer to time and time again in your career.

Foolish Assumptions

I make a few assumptions about you as a reader and have written this book with these assumptions in mind:

♦ You are interested in obtaining the CCNA. After all, the focus of this book is helping you pass the exams.

♦ You will study hard and do as much hands-on work as possible. There is a lot of content on the exam, and you will most likely need to read over the information a few times to ensure that you understand the content. You should also experiment as much as possible after you read a particular topic

How This Book Is Organized

Like all All-In-One For Dummies books, chapters are organized into minibooks. The chapters in each minibook are related by a specific exam theme or topic:

♦ Book I: Networking Basics

♦ Book II: TCP/IP

♦ Book III: Switching with Cisco Switches

♦ Book IV: Routing With Cisco Routers

♦ Book V: Wireless Networks

♦ Book VI: Network Security

♦ Book VII: Wide Area Networks (WAN)

Appendix A gives you an overview of what you can find on the CD-ROM that accompanies the book. Appendix B shows you the ins and outs of exam preparation.

Icons Used in This Book

I use a number of icons in this book to draw your attention to pieces of useful information.

Information that would be helpful to you in the real world is indicated with a Tip icon. Expect to find shortcuts and timesavers here.

This icon is used to flag information that may be useful to remember on the job.

Information that could cause problems to you or to the computer is indicated with a Warning icon. If you see a Warning icon, make sure you read it. The computer you save may be your own.

Detailed information that is not needed for the exams or that is a step above the knowledge you absolutely need to know for the exams is indicated with a Technical Stuff icon.

Where to Go from Here

Appendix B is a guide to the ins and outs of the CCNA exams. It tells you the chapters that cover each required subject. Or you can just turn the page and begin at the beginning.

Let’s get started!

Book I

Networking Basics

Contents at a Glance

Chapter 1: Introducing Computer Networks

Purpose of Computer Networks

Operation Flow of Computer Networks

Topologies of Computer Networks

Chapter 2: The OSI Reference Model

Introduction to the OSI Reference Model

Seven Layers

Benefits of the OSI Reference Model

Chapter 3: Introducing the TCP/IP Protocol Suite

Introduction to the TCP/IP Protocol Suite

Layer 7: Application

Layer 6: Presentation

Layer 5: Session

Layer 4: Transport

Layer 3: Network

Layer 2: Data Link

Layer 1: Physical

Chapter 4: Data Encapsulation

Introducing Data Encapsulation

Chapter 5: Binary, Hexadecimal, and Decimal Numbering Systems

Decimal Numbers

Binary Numbers

Hexadecimal Numbers

Chapter 6: Local-Area Networks (LANs)

Introduction to Local-Area Networks

Ethernet Networking

Ethernet Standards

Ethernet in the OSI Model

Chapter 7: Introducing Wide-Area Networks (WANs)

Introducing Wide-Area Networks

Dedicated Leased Line Connections

Circuit-Switched Connections

Packet-Switched Connections

Cell-Switched Connections

Chapter 8: Introducing Wireless Networks

Benefits and Costs of Wireless Networks

Security Risks

Chapter 9: Network Design

Cisco Hierarchical Network Model

Core Layer

Distribution Layer

Access Layer

Benefits

Chapter 10: Introducing Cisco Hardware and Software

Introducing Cisco Products

Introducing Cisco Device Configurations

Meet the Cisco IOS User Interface

Chapter 1: Introducing Computer Networks