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Network Fundamentals, CCNA Exploration Companion Guide

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  • Description
  • Sample Content
  • Updates
  • Copyright 2011
  • Dimensions: 8" x 9-1/4"
  • Edition: 1st
  • eBook (Watermarked)
  • ISBN-10: 0-13-287742-2
  • ISBN-13: 978-0-13-287742-8

Network Fundamentals, CCNA Exploration Companion Guide is the official supplemental textbook for the Network Fundamentals course in the Cisco® Networking Academy® CCNA® Exploration curriculum version 4. The course, the first of four in the new curriculum, is based on a top-down approach to networking. The Companion Guide, written and edited by Networking Academy instructors, is designed as a portable desk reference to use anytime, anywhere. The book’s features reinforce the material in the course to help you focus on important concepts and organize your study time for exams.

New and improved features help you study and succeed in this course:

  • Chapter objectives–Review core concepts by answering the focus questions listed at the beginning of each chapter.
  • Key terms–Refer to the updated lists of networking vocabulary introduced and highlighted in context in each chapter.
  • Glossary–Consult the comprehensive glossary with more than 250 terms.
  • Check Your Understanding questions and answer key–Evaluate your readiness with the updated end-of-chapter questions that match the style of questions you see on the online course quizzes. The answer key explains each answer.
  • Challenge questions and activities–Strive to ace more challenging review questions and activities designed to prepare you for the complex styles of questions you might see on the CCNA exam. The answer key explains each answer.  

How To–Look for this icon to study the steps you need to learn to perform certain tasks.

Packet Tracer Activities– Explore networking concepts in activities interspersed throughout some chapters using

Packet Tracer v4.1 developed by Cisco. The files for these activities are on the accompanying CD-ROM.

Also available for the Network Fundamentals Course

Network Fundamentals, CCNA Exploration Labs and Study Guide

ISBN-10: 1-58713-203-6

ISBN-13: 978-1-58713-203-2

Companion CD-ROM

**See instructions within the ebook on how to get access to the files from the CD-ROM that accompanies this print book.**

The CD-ROM provides many useful tools and information to support your education:

  • Packet Tracer Activity exercise files v4.1
  • VLSM Subnetting Chart
  • Structured Cabling Exploration Supplement
  • Taking Notes: a .txt file of the chapter objectives
  • A Guide to Using a Networker’s Journal booklet
  • IT Career Information
  • Tips on Lifelong Learning in Networking

This book is part of the Cisco Networking Academy Series from Cisco Press®. The products in this series support and complement the Cisco Networking Academy online curriculum.

Table of Contents


Chapter 1 Living in a Network-Centric World


Key Terms

Communicating in a Network-Centric World

    Networks Supporting the Way We Live

    Examples of Today’s Popular Communication Tools

    Networks Supporting the Way We Learn

    Networks Supporting the Way We Work

    Networks Supporting the Way We Play

Communication: An Essential Part of Our Lives

    What Is Communication?

    Quality of Communication

The Network as a Platform

    Communicating over Networks

    Elements of a Network

    Converged Networks

The Architecture of the Internet

    The Network Architecture

    Fault-Tolerant Network Architecture

    Scalable Network Architecture

    Providing Quality of Service

    Providing Network Security

Trends in Networking

    Where Is It All Going?

    Networking Career Opportunities


Activities and Labs

Check Your Understanding

Challenge Questions and Activities

To Learn More

Chapter 2 Communicating over the Network


Key Terms

The Platform for Communications

    The Elements of Communication

    Communicating the Messages

    Components of the Network

    End Devices and Their Role on the Network

    Intermediary Devices and Their Role on the Network

    Network Media

LANs, WANs, and Internetworks

    Local-Area Networks

    Wide-Area Networks

    The Internet: A Network of Networks

    Network Representations


    Rules That Govern Communications

    Network Protocols

    Protocol Suites and Industry Standards

    Interaction of Protocols

    Technology-Independent Protocols

Using Layered Models

    The Benefits of a Layered Model

    Protocol and Reference Models

    TCP/IP Model

    Communication Process

    Protocol Data Units and Encapsulation

    Sending and Receiving Process

    OSI Model

    Comparing the OSI Model to the TCP/IP Model

Network Addressing

    Addressing in the Network

    Getting Data to the End Device

    Getting Data Through the Internetwork

    Getting Data to the Right Application


Activities and Labs

Check Your Understanding

Challenge Questions and Activities

To Learn More

Chapter 3 Application Layer Functionality and Protocols


Key Terms

Applications: The Interface Between the Networks

    OSI and TCP/IP Model

    Application Layer Software

    User Applications, Services, and Application Layer Protocols

    Application Layer Protocol Functions

Making Provisions for Applications and Services

    Client/Server Model


    Application Layer Services and Protocols

    Peer-to-Peer (P2P) Networking and Applications

Application Layer Protocols and Services Examples

    DNS Services and Protocol

    WWW Service and HTTP

    E-Mail Services and SMTP/POP Protocols

    E-Mail Server Processes: MTA and MDA



    File-Sharing Services and SMB Protocol

    P2P Services and Gnutella Protocol

    Telnet Services and Protocol


Activities and Labs

Check Your Understanding

Challenge Questions and Activities

To Learn More

Chapter 4 OSI Transport Layer


Key Terms

Roles of the Transport Layer

    Purpose of the Transport Layer

    Supporting Reliable Communication

    TCP and UDP

    Port Addressing

    Segmentation and Reassembly: Divide and Conquer

TCP: Communicating with Reliability

    Making Conversations Reliable

    TCP Server Processes

    TCP Connection Establishment and Termination

    TCP Three-Way Handshake

    TCP Session Termination

    TCP Acknowledgment with Windowing

    TCP Retransmission

    TCP Congestion Control: Minimizing Segment Loss

UDP: Communicating with Low Overhead

    UDP: Low Overhead Versus Reliability

    UDP Datagram Reassembly

    UDP Server Processes and Requests

    UDP Client Processes



Check Your Understanding

Challenge Questions and Activities

To Learn More

Chapter 5 OSI Network Layer


Key Terms


    Network Layer: Communication from Host to Host

    IPv4: Example Network Layer Protocol

    IPv4 Packet: Packaging the Transport Layer PDU

    IPv4 Packet Header

Networks: Dividing Hosts into Groups

    Creating Common Groups

    Why Separate Hosts into Networks?

    Dividing Networks from Networks

Routing: How Data Packets Are Handled

    Device Parameters: Supporting Communication Outside the Network

    IP Packets: Carrying Data End to End

    Gateway: The Way Out of the Network

    Route: A Path to a Network

    Destination Network

    Next Hop: Where the Packet Goes Next

    Packet Forwarding: Moving the Packet Toward Its Destination

Routing Processes: How Routes Are Learned

    Static Routing

    Dynamic Routing

    Routing Protocols



Check Your Understanding

Challenge Questions and Activities

To Learn More

Chapter 6 Addressing the Network: IPv4


Key Terms

IPv4 Addresses

    Anatomy of an IPv4 Address

    Binary-to-Decimal Conversion

    Decimal-to-Binary Conversions

    Addressing Types of Communication: Unicast, Broadcast, Multicast

IPv4 Addresses for Different Purposes

    Types of Addresses in an IPv4 Network Range

    Subnet Mask: Defining the Network and Host Portions of the Address

    Public and Private Addresses

    Special Unicast IPv4 Addresses

    Legacy IPv4 Addressing

Assigning Addresses

    Planning to Address the Network

    Static or Dynamic Addressing for End-User Devices

    Selecting Device Addresses

    Internet Assigned Numbers Authority (IANA)


Calculating Addresses

    Is the Host on My Network?

    Calculating Network, Hosts, and Broadcast Addresses

    Basic Subnetting

    Subnetting: Dividing Networks into Right Sizes

    Subnetting a Subnet

Testing the Network Layer

    Ping Testing the Local Stack

    Ping Gateway: Testing Connectivity to the Local LAN

    Ping Remote Host: Testing Connectivity to Remote LAN

    Traceroute (tracert): Testing the Path

    ICMPv4: The Protocol Supporting Testing and Messaging

Overview of IPv6



Check Your Understanding

Challenge Questions and Activities

To Learn More

Chapter 7 OSI Data Link Layer


Key Terms

Data Link Layer: Accessing the Media

    Supporting and Connecting to Upper-Layer Services

    Controlling Transfer Across Local Media

    Creating a Frame

    Connecting Upper-Layer Services to the Media


MAC Techniques: Placing Data on the Media

    MAC for Shared Media

    MAC for Nonshared Media

    Logical Topology Versus Physical Topology

MAC: Addressing and Framing Data

    Data Link Layer Protocols: The Frame

    Framing: Role of the Header

    Addressing: Where the Frame Goes

    Framing: Role of the Trailer

    Sample Data Link Layer Frames

Putting It All Together: Following Data Through an Internetwork



Check Your Understanding

Challenge Questions and Activities

To Learn More

Chapter 8 OSI Physical Layer


Key Terms

Physical Layer: Communication Signals

    Purpose of the Physical Layer

    Physical Layer Operation

    Physical Layer Standards

    Physical Layer Fundamental Principles

Physical Signaling and Encoding: Representing Bits

    Signaling Bits for the Media

    Encoding: Grouping Bits

    Data-Carrying Capacity

Physical Media: Connecting Communication

    Types of Physical Media

    Copper Media

    Media Connectors



Check Your Understanding

Challenge Questions and Activities

To Learn More

Chapter 9 Ethernet


Key Terms

Overview of Ethernet

    Ethernet: Standards and Implementation

    Ethernet: Layer 1 and Layer 2

    Logical Link Control: Connecting to the Upper Layers

    MAC: Getting Data to the Media

    Physical Implementations of Ethernet

Ethernet: Communication Through the LAN

    Historic Ethernet

    Legacy Ethernet

    Current Ethernet

    Moving to 1 Gbps and Beyond

Ethernet Frame

    Frame: Encapsulating the Packet

    Ethernet MAC Address

    Hexadecimal Numbering and Addressing

    Another Layer of Addressing

    Ethernet Unicast, Multicast, and Broadcast

Ethernet MAC

    MAC in Ethernet

    CSMA/CD: The Process

    Ethernet Timing

    Interframe Spacing and Backoff

Ethernet Physical Layer

    10- and 100-Mbps Ethernet

    1000-Mbps Ethernet

    Ethernet: Future Options

Hubs and Switches

    Legacy Ethernet: Using Hubs

    Ethernet: Using Switches

    Switches: Selective Forwarding

Address Resolution Protocol (ARP)

    Resolving IPv4 Addresses to MAC Addresses

    Maintaining a Cache of Mappings

    ARP Broadcast Issues



Check Your Understanding

Challenge Questions and Activities

To Learn More

Chapter 10 Planning and Cabling Networks


Key Terms

LANs: Making the Physical Connection

    Choosing the Appropriate LAN Device

    Device Selection Factors

Device Interconnections

    LAN and WAN: Getting Connected

    Making LAN Connections

    Making WAN Connections

Developing an Addressing Scheme

    How Many Hosts in the Network?

    How Many Networks?

    Designing the Address Standard for Your Internetwork

Calculating the Subnets

    Calculating Addresses: Case 1

    Calculating Addresses: Case 2

Device Interconnections

    Device Interfaces

    Making the Device Management Connection



Check Your Understanding

Challenge Questions and Activities

To Learn More

Chapter 11 Configuring and Testing Your Network


Key Terms

Configuring Cisco Devices: IOS Basics

    Cisco IOS

    Access Methods

    Configuration Files

    Introducing Cisco IOS Modes

    Basic IOS Command Structure

    Using CLI Help

    IOS Examination Commands

    IOS Configuration Modes

Applying a Basic Configuration Using Cisco IOS

    Naming Devices

    Limiting Device Access: Configuring Passwords and Banners

    Managing Configuration Files

    Configuring Interfaces

Verifying Connectivity

    Test the Stack

    Testing the Interface

    Testing the Local Network

    Testing Gateway and Remote Connectivity

    Tracing and Interpreting Trace Results

Monitoring and Documenting Networks

    Basic Network Baselines

    Capturing and Interpreting Trace Information

    Learning About the Nodes on the Network



Check Your Understanding

Challenge Questions and Activities

To Learn More

Appendix Check Your Understanding and Challenge Questions Answer Key


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