Sams teach yourself networking in 24 hours

433 Pages·2009·4.338 MB·English

by  Black, Uyless D., Habraken, Joseph W

Uyless Black
SamsTeachYourself
Networking
24
in
Hours
800 East 96th Street,Indianapolis,Indiana,46240 USA
Sams Teach Yourself Networking in 24 Hours Editor-in-Chief
Copyright © 2009 by Pearson Education,Inc. Mark Taub
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ISBN-13: 978-0-768-68576-3
ISBN-10: 0-768-68576-1 Managing Editor
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Black,Uyless D. Jovana San Nicolas-
Sams teach yourself networking in 24 hours / Uyless Black. — 4th ed. Shirley
p. cm. — (Sams teach yourself in 24 hours)
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Previous ed.: Sams teach yourself networking in 24 hours / by Joe Habraken. 3rd ed. 2004.
Karen A.Gill
Includes index.
ISBN 978-0-7686-8576-3 (pbk.) Indexer
1. Computer networks. I. Habraken,Joseph W.,1954- Sams teach yourself networking in 24 Erika Millen
hours. II. Title.
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Table of Contents
Introduction 1
HOUR 1: An Overview of Networking 3
What Is a Network? What Is Networking? ..........................................................4
Why Build a Network?..........................................................................................6
How Networks Are Put Together............................................................................8
The Network Architecture: Combining the Physical and Logical Components....8
Two Varieties of Networks: Local and Wide Area ..............................................11
How the Internet Relates to Your Network..........................................................13
Connecting to the Internet..................................................................................14
Why the Internet Matters....................................................................................15
Intranets, Extranets, and internets......................................................................16
Summary..............................................................................................................16
Q&A ....................................................................................................................16
HOUR 2: The Benefits of Networking 19
Computing Before Computer Networks..............................................................19
Networking’s Breakthrough: Packet-Switched Data ..........................................21
Benefits of Networking........................................................................................25
Summary..............................................................................................................27
Q&A ....................................................................................................................28
HOUR 3: Getting Data from Here to There: How Networking Works 29
Network Protocols................................................................................................29
The OSI Model (and Why You Should Be Familiar with It) ..............................30
The Internet Model..............................................................................................36
Addresses: Network or Layer 3 Addresses ..........................................................37
MAC or Layer 2 Address: That Is to Say, Ethernet Addresses ............................40
Using Addresses to Relay Traffic..........................................................................40
Overview of the Principal Protocols....................................................................42
IPX........................................................................................................................45
And Farewell NetBIOS and NetBEUI ..................................................................46
Summary..............................................................................................................46
Q&A ....................................................................................................................46
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Teach Yourself Networking in 24 Hours
HOUR 4: Computer Concepts 49
Numbers, Magnitudes, and Fractions ................................................................49
Computer Hardware............................................................................................50
Network Cards ....................................................................................................58
Operating System (OS) and Other Software ......................................................62
Summary..............................................................................................................69
Q&A ....................................................................................................................69
HOUR 5: Network Concepts 71
Elements of a Network ........................................................................................71
The Need for Speed..............................................................................................72
Router ..................................................................................................................74
The Client/Server Model......................................................................................79
Server....................................................................................................................80
Server Operating Systems....................................................................................83
Media ..................................................................................................................88
Summary..............................................................................................................91
Q&A ....................................................................................................................92
HOUR 6: Extending LANs with Wide Area Networks (WANs) 95
What Is a WAN?..................................................................................................95
Components of a WAN........................................................................................97
User-Network Interface, Inner-Network Interface, and
Network-Network Interface..................................................................................99
Residential Broadband......................................................................................101
Layer 1 WAN Carrier Systems: T1 and SONET ................................................103
Layer 2 for WANs: ATM and MPLS ..................................................................108
Putting More Pieces Together............................................................................112
Summary............................................................................................................114
Q&A ..................................................................................................................114
HOUR 7: Mobile Wireless Networking 117
Understanding Wireless Networking ................................................................117
A Brief History of Mobile Wireless Networks....................................................119
The Cell Concept................................................................................................120
Wi-Fi ..................................................................................................................122
Bluetooth............................................................................................................123
v
Contents
Are Wi-Fi and Bluetooth in Competition?........................................................125
Frequency Interference Between Wi-Fi and Bluetooth?....................................125
Security Considerations with Wireless Networks..............................................125
Implementation Considerations ......................................................................126
Summary............................................................................................................127
Q&A ..................................................................................................................127
HOUR 8: Remote Networking 129
Early “Remote Control” ....................................................................................129
Remote Control for System Administration......................................................130
Modems and Remote Access..............................................................................131
Modern Remote Access Protocols and Procedures............................................132
The Point-to-Point Protocol (PPP)......................................................................133
Using the Internet for Remote Access: The VPN ..............................................137
Remote Access Hardware: Build or Buy?..........................................................138
Summary............................................................................................................140
Q&A ..................................................................................................................140
HOUR 9: Planning for the Network 143
Best Practices and Building Computer Networks..............................................143
Planning Best Practices: Plan, Design, Implement, and Tune ........................145
Applying the Best Practices ..............................................................................147
Interoperability by Using Standards ................................................................149
Improving Security Using Best Practices ..........................................................150
Summary............................................................................................................153
Q&A ..................................................................................................................153
HOUR 10: Designing a Network 155
Step 1: Identify the Uses of the Network ..........................................................156
Step 2: List Which Tasks Execute on Which Computers ..................................159
Step 3: Select the Type of Network: To Centralize or Not to Centralize ..........161
Step 4: “Draw” the Network..............................................................................167
Step 5: Write the Specification..........................................................................174
Step 6: Build the Network..................................................................................176
Summary............................................................................................................177
Q&A ..................................................................................................................177
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Teach Yourself Networking in 24 Hours
HOUR 11: Selecting Network Hardware and Software 179
Evaluating the Server Hardware ......................................................................180
Evaluating the “Interworking” Hardware........................................................181
Hardware Selection Considerations for Ethernet Networks..............................182
Selecting the Network Type: Client/Server or Peer to Peer................................185
Peer-to-Peer OSs ................................................................................................188
Peer-to-Peer Networking with Microsoft Windows............................................189
Evaluating NOSs................................................................................................192
The Network “Bottleneck” ................................................................................196
A Word Regarding Network Protocols ..............................................................197
Summary............................................................................................................198
Q&A ..................................................................................................................198
HOUR 12: Assembling a Network 199
Before Installation ............................................................................................199
Installing Adapter Cards ..................................................................................202
Working with Wiring ........................................................................................207
A Word About Wireless Networking..................................................................210
Summary............................................................................................................210
Q&A ..................................................................................................................210
HOUR 13: Network Applications 211
Introduction to Groupware................................................................................212
Email..................................................................................................................213
Scheduling and Calendars................................................................................219
Contact Management........................................................................................221
A Sampler of Network-Based Applications ......................................................223
Summary............................................................................................................228
Q&A ..................................................................................................................229
HOUR 14: Connecting to the Internet: Initial Operations 231
Origins of the Internet ......................................................................................231
ISPs ....................................................................................................................233
IXPs....................................................................................................................234
BGP ....................................................................................................................235
Peering ..............................................................................................................236
Considerations for Choosing an ISP..................................................................237
vii
Contents
How and Why TCP/IP Was Created..................................................................238
Ports....................................................................................................................240
Sockets................................................................................................................241
IP Features..........................................................................................................242
TCP Features......................................................................................................243
UDP Features......................................................................................................244
Summary............................................................................................................244
Q&A ..................................................................................................................245
HOUR 15: Connecting to the Internet: Key Supporting Operations 247
The DNS ............................................................................................................247
IP Addresses........................................................................................................255
Getting Your IP Addresses..................................................................................258
Configuring Network Devices with IP Addresses..............................................259
DHCP..................................................................................................................261
The Web ............................................................................................................264
Ideas for Establishing a Website........................................................................267
Summary............................................................................................................269
Q&A ..................................................................................................................270
HOUR 16: Microsoft Networking 271
Microsoft’s Logical Network Structure ..............................................................272
Installing and Configuring a Microsoft Server ................................................274
Configuring Network Protocols in Windows ....................................................280
Sharing Folders and Printers on the Network ..................................................282
Managing a Microsoft Server............................................................................285
Future of Windows Server 2003 ........................................................................286
Windows Server 2008........................................................................................287
Summary............................................................................................................287
Q&A ..................................................................................................................287
HOUR 17: UNIX and Linux Networking 289
How UNIX Got Its Start......................................................................................289
Basic UNIX Concepts ........................................................................................291
UNIX/LINUX as a Network Platform................................................................292
Network Services and Settings on a Linux Server............................................293
Options for Sharing Files ..................................................................................295
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Teach Yourself Networking in 24 Hours
Summary of Network Servers............................................................................297
Summary............................................................................................................298
Q&A ..................................................................................................................298
HOUR 18: Putting the Pieces Together 301
Review of Internet Layered Model ....................................................................301
Key Network Components’ Position in the Layers............................................302
Names, Addresses, and Sockets: The Cogs of Communications......................304
Relationships of Names, Addresses, and Sockets..............................................305
Common Locations of Components at Network Interfaces ............................306
HOUR 19: Role of the Network Administrator 309
Information Technology Jobs............................................................................310
Computer Networking Education and Certification ........................................311
Additional Thoughts on Managing the Planning
and Installation Processes ................................................................................313
A Few Thoughts on Budgets..............................................................................313
Managing Network Projects..............................................................................315
Summary............................................................................................................317
Q&A ..................................................................................................................318
HOUR 20: Security 319
Basic Terms........................................................................................................320
Security Threats..................................................................................................321
Security Defenses................................................................................................322
Securing the Internal Network..........................................................................323
Dealing with Viruses..........................................................................................328
Protecting the Internal Network from External Attacks ..................................330
Other Key Security Protocols..............................................................................332
Wireless Networks..............................................................................................335
Best Practices for Securing a Network ..............................................................336
Summary............................................................................................................337
Q&A ..................................................................................................................338
HOUR 21: Managing a Network 339
Upgrading the Network ....................................................................................339
Managing Hardware Upgrades and Growth....................................................340
Managing Software Upgrades and Growth......................................................341
ix
Contents
Dealing with NOS and Client Licensing ..........................................................343
Backing Up Network Data ................................................................................345
Network and Disaster Recovery Planning........................................................349
Archives..............................................................................................................353
Summary............................................................................................................353
Q&A ..................................................................................................................354
HOUR 22: Network Troubleshooting 355
MIBs and SNMP ................................................................................................355
Troubleshooting Routers....................................................................................356
Monitoring Server Hardware ............................................................................357
Processor Performance ......................................................................................358
Hard Drive Performance and Space..................................................................361
Memory Utilization............................................................................................363
Using Event Logs to Track Problems..................................................................364
TCP/IP Connectivity Command-Line Tools......................................................366
Summary............................................................................................................371
Q&A ..................................................................................................................372
HOUR 23: A Day in the Life of a Network Administrator 373
Your Job as an Administrator............................................................................373
Daily Tasks ........................................................................................................376
Strategies for Supporting Users..........................................................................378
Establishing Network Policies............................................................................379
Summary............................................................................................................380
Q&A ..................................................................................................................380
HOUR 24: Where Are Networks Going from Here? 383
Continued Growth of Linux..............................................................................383
Nationwide Variation of Wi-Fi: WiMax............................................................384
Computing with Clouds....................................................................................385
Computers, Bioengineering, and the Clouds....................................................386
Glossary 389
Index 397