Network Administrator's Reference

Tere1 Parnell Christopher Null

Osborne / McGraw-Hill Berkeley New York St. Louis San Francisco

Auckland Bogota Hamburg London Madrid Mexico City Milan Montreal New Delhi Panama City

Paris Säo Paulo Singapore Sydney Tokyo Toronto

CONTENTS

Acknowledgments xxi Introduction xxv

EEffll Building a Network

T 1 Front-Office Functions 3

It's the (Seemingly) Little Things That Count 4 Scheduling and Time Management 4 Personal Information Management 5 Contact Management 6 Call Management 6 Order Entry 6 Customer Service 7 Document Preparation 7 Research 8 Document Management and Retrieval 8 Electronic Mail 8 Internal News Management 8

V

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Timekeeping 8 Preparing Expense Reports 9

On to the Back Door 9

T 2 Back-Office Functions 11

Where Is the Back End? 12 Systems That Support Operations 12 Systems That Provide Services to Users 13

The Future 15

T 3 Electronic Commerce 17

Using What You've Got 18 EDI 19 Making the Jump to the Consumer 20

Getting What You Need 20 Electronic Storefronts 21 Electronic Payment Systems 22 Security 23 Outsourcing and Doing Without 27

FTffTTI

T 4 Layer 7 and What It Means to You 31

What's an Application? 32 Taking Instruction 33 Speaking the Language 34

How Applications Work 36 Capture 37 Transmit 37 Store 37 Retrieve 37 Manipulate 37 Display 38

What Does This Have to Do with Layer 7? 38 Applications and the Internet 39

Applications Are Born Stupid 39

T 5 Where Applications Live 41

Server Farming 42 Do Servers Grow on Farms? 43 Enterprise-Wide Access to Information 43

Contents

Distribute Processing Load Across Specialized Platforms . . 46 Implementations of Distributed Computing Systems 46

Distributed Application Processing 47 Distributed Databases 47 Data Warehousing 47

Building Blocks of Distributed Computing Systems 48 Relational Databases 48 Structured Query Language 49 Middleware 49 Data Propagation 52

Network Requirements of a Server Farm 53 Indications of Bandwidth Drought on the Farm 54 Other Causes and Cures for Slow Performance on

the Server Farm 55 Location of Data and Applications 55 Inadequate Hardware 55 Buying the Farm 56

T 6 Application Neighborhoods 57

The Apps in the 'Hood: Distributed Applications 58 Distributed Databases 58 The Nuts and Bolts of Client/Server Computing 60 Multitiered Architectures 65

Planned Neighborhoods 66 Finding Your Way Through the 'Hood 72

T 7 What Every Application Should Know 73

Problems with Distributed Data 74 Transaction Tracking Essentials 74 Transaction Processing on the Web 76

MiddleSpeak 76 One Size Does Not Fit All 77 Web Middleware 78 Common Object Request Broker Architecture (CORBA) . . . 79

T 8 Applications Going the Distance 83

Directory Assistance, Please 84 Getting on the List 85 Containing the List 86

Safeguarding the Directory: Replication and Partitioning 87

Locking It Down 88 A Directory of Directory Services 88

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X.500 88 Banyan StreetTalk 90 Novell Directory Services (NDS) 91 Windows NT Server Directory Services 92 DCE Directory Services, the Open Group 94 Netscape Directory Server 94

Moving on Down the Chain 94

T 9 Layer 6 and What It Means to You 95

Happenings at Layer 6 96 Data Encryption and Data Compression 98 Minding Your (Data) Grammar 98 Presentation Layer Functional Units 98

But What Does It Mean? 101

M71TIT1

The Infrastructure

T 10 Operating Environments 105

Layer 5 and What It Means to You 106 NetWare Core Protocol (NCP) 108 Burst Mode Protocol (BMP) 109 Remote Procedure Call (RPC) 110 Banyan VINES Remote Procedure Call (NetRPC) I l l Network Basic Input /Output System (NetBIOS) 112 Server Message Block Protocol (SMB) 113

NetBIOS Names 114 SMB Protocol Variants 114 Security 115 Browsing the Network 115 CIFS: The Latest Incarnation? 115 An Example SMB Exchange 115

Named Pipes 116 TCP 117 FTP, SMTP, SNMP, and Telnet 118

File Transfer Protocol (FTP) 118 Simple Mail Transfer Protocol (SMTP) 118 Simple Network Management Protocol (SNMP) 119 Telnet 119

What Layer 5 Tells You About Your Network 119 ISO Technical Documents 120 RFCs 121 WebSites 121

• 11 Managing and Monitoring Software 123

Traffic Management 124 Packet Generators 124 Network Analyzers 125 Application Testers 125

Application Management 125 Device Management 126

Simple Network Management Protocol (SNMP) 126 Web-Based Network Management 131 Java Management API 132

Management Platforms 133 IETF Network Management Developments 134

T 12 Security 135

Software vs. Hardware Security 136 How Secure Is Your Operating System? 136

Microsoft 137 Novell 138 UNIX 139

Firewalls 140 Types of Internet Attacks 140 How Firewalls Work 142 The Pack 146

Cryptography 147 Authentication and Encryption 147 Virtual Private Networks 148

Secure Messaging 149 PGP 149 S/MIME 151 Enterprise Solutions 153

Web Security 154 Browsers 154 Microsoft Internet Explorer 155 Cookies 155 Java, JavaScript, and ActiveX 155 Web Security Tools 156

Viruses 157 Antivirus Software 157

Intrusion Detection 158 Security Auditing Tools and Scanners 158 Packet Sniffers 159

Physical Security 160 Location, Location, Location 160 Social Engineering 160

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The Future 161 Security Consolidation 161 The New IP 162

T 13 The Desktop 163

Finding Your Desktop 164 The Distributed Computing Environment (DCE) 164 Desktop Impact of Distributed Computing Environment . . 166

Functions of the Desktop 167 Types of Desktops 167

Inventory 168 Standards 168 Service-Level Agreements 169 Training 169 Cost of Ownership 170

Heart of Hardware: Microprocessors 170 Microchips and Salsa: A Primer 171 Microprocessors in Practice: What You'll Find

on Desktops 180 The Softer Side of the Desktop:

Software Clients 188 UNIX 189 Windows 192 WinFrame 193

Managing the Desktop 194 Zero Administration for Windows Initiative 194 Wired for Management (WfM) Initiative 194 Desktop Management Interface (DMI) 195 Where It Begins and Ends 196

T 14 The Server 199

Server Functions 200 File Servers 201 Application Servers 201 Database Servers 202 Web Servers 202 Mail Servers 202 Print Servers 203 Fax Servers 203 Remote Access Servers 203 Backup Servers 203

Server Marketing Categories 204 Workgroup /Department Servers 204 Midrange Servers 204

Enterprise Servers 205 Server Architecture 205

Server Design: The Big Picture 206 Server Motherboard Design 208

Microprocessors 208 Intel 208 AMD 216 Cyrix 217 Sun Microsystems 217 Digital Equipment Corp. (R.I.P.) 218 Silicon Graphics 219 Motorola 219 Hewlett-Packard 219 IBM 220 One Chip or More? 220

Memory 221 The Two Basic Memory Types 221 Memory Cards 223 RAM Technologies 225 Video and Graphics RAM 228 Further Reading 229

Input/Output 229 Hard Disk Drives 229 RAID 235 Controller Cards 241 External Storage Systems 242 Choosing an I / O Strategy 242 Additional Resources 242

Slots Galore 243 ISA 243 EISA 243 MicroChannel 244 VESA 244 PCI 244 AGP 245 PC Cards 245 USB 245 1394 246

Server Management 246 Intel LANDesk 246 Hewlett-Packard Open View 246 Server Management Hardware 247

Backup 247 Disaster Planning 247

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Tape and Tape Drives 248 Other Backup Devices 250

Other Server Considerations 250 Server NICs 251 Power Supplies 251 UPSs 252 CD-ROM Drives 252 CYA: Technical Support and Warranties 252

Name Brand or Clone? 253 How Much Will It Cost? 253 Upgrading 254 Working with Servers 254

ESD 254 Tools 255 Storage 255

Further Reading 256

T 1 5 The Glue 257

Connectivity 101 258 Types of Backbones 260 Why Build a Backbone? 262 How Do You Build a Backbone? 264 The Effects of Excessive Internetwork Traffic 266 Causes and Cures for a Clogged Backbone 266 The Final Analysis 268 What You Gain 268 Selecting a High-Speed Backbone Protocol 268

Local Area Protocols 269 Fiber Distributed Data Interface (FDDI) 269 The Topology 275

lOOVG-AnyLAN 280 So Close, but So Far from 10Base-T 280

100Base-T 288 A Smorgasbord of Specs 289 Understanding the Differences Between

100Base-T and 10Base-T 292 Interoperability and Obstacles 293

Gigabit Ethernet 296 The 802.3 Standard 298 How Gigabit Ethernet Differs from 100Base-T 299 Scalability Considerations 301 Cabling Considerations 301 Management 302 Cost 302

Contents

Performance 302 Support for Voice and Video 303

Fibre Channel 309 Going Through Channels 309 The Standard and Its Supporting Groups 310 How Do They Do That? 311 Cabling Considerations 317 Installation and Configuration 319 Advantages: Fibre Channel vs. ATM 320 Disadvantages 321

Asynchronous Transfer Mode 321 How It Started 322 Who Started It 322 ATM: The Short Answer 322 If ATM Is the Answer, What Were the Questions? 323 How It All Works Together 327 The ATM and the OSI Model 332 ATM Migration Issues 333 Expect to Phase It In 342 The Promised LAN 348

Moving on Down the Line 349

T 16 The Cabling 351

All That Glistens Isn't Copper 352 Cabling Primer 352 The TIA and EIA Cabling Standards 353

Work Area Wiring 353 Horizontal Wiring 353 Telecommunications Closets 353 Equipment Rooms and Cross-Connects 354 Backbone Wiring 354 Entrance Facilities 354

Reaching Up from Layer 1 354 A Segment Defined 354 Creating Internetworks 355 The Bridging Primer 357 Bridge Performance Issues 365 The Router Primer 366 The Router Shopping Guide 368 Planning Segmented Networks 369 Microsegmentation 370

Switching 370 Making the Switch 370 Which Switch? 374

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Analysis Is Key 380 10/100/1000 Switching 382

Full-Duplex Protocols 383 A Time for Everything 384

Bridging 384 Routing 384 Switching 384 Virtual LANs 384

The 'Nets

T 17 Intranetsand Extranets 387

Intranets Demystified 388 Making New Rules 388

Intranets: Enabling Technologies 389 Hypertext Markup Language (HTML) 389 Hypertext Transfer Protocol (HTTP) 393 Component Technology 395 Push 397

Extranets 399 Standard Data Exchange Formats 399 Security 400

The Local'Nets 400

T 18 The Internet 401

A Network Is a Network 402 How It All Began 402 Internet Protocol (IP) 402 Growth Factors 403 The Business Side of the Internet 406

Internet Service Providers 407 PPP and SLIP Connections 407 Selecting an Internet Service Provider 407

Internet Domain Names 410 Connecting to the Internet 412

Internet Client Software 413 E-Mail 413 NetNews 414 FTP 416 World Wide Web 416

Conclusion 417

T 19 Wide Area Connections 419 So You Think You're Ready for the Long Haul 420

The Wide Area Defined 421 Carrier Services 427 Performance Over the Wide Area 429 Tests to Confirm Insufficient WAN Bandwidth 431 Requirements for Wide Area Protocols 432 Ready to Roll? 433

Codes and Signaling 433 Codes: Computer Words 434 Analog Signaling 434 Digital Signaling 438 The Importance of Being Well-Modulated 438 It's Not Only How You Say It, but Also What You Say . . . 440 And What Does This Have to Do with My LAN? 444

Basic Trunking 445 Two Tin Cans and a String = a Loop 446 Are You Dedicated, or Are You Going to Switch? 446 Pack Your Trunk 448 Putting It Together 456 Now That Your Trunk Is Packed, We Can Move On 457 Circuit Switching and Packet Switching 457

Basic Transmission 458 Transmission Facilities: An Overview 459 How It Works in Practice 466

The Regulatory Environment: Past, Present, and Future 468 First Is the Deed 468 The 1956 Consent Decree 469 The Carterphone Decision (1968) 469 The U.S. District Court's Modification of Final Judgment . . 470 The Telecommunications Act of 1996 (February 8,1996) . . . 474 Make Your Mark 476 What Does All This Mean to You? 478

The Players 479 The Roster 479 The Lineup 480 Management 486 Now We're Ready to Play 486

Determining the Requirements for Wide Area Connections . . . . 487 The Bandwidth Question: How Much Speed? 487 Flexibility 494 Recommendations 494 WAN Usage Survey 495

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T 20 Wide Area Protocols and Devices 497

Tl Services 498 Tl Defined 498 Tl Transmission Facilities 503 Carrier Systems 504 Tl Equipment 508 Flexibility 512 Availability 513 Cost 513 Tl: A Telecommunications Basic 513

Switched Multimegabit Data Service 513 What Is . . . ? 515 Where . . . ? 518 H o w . . . ? 519 W h y . . . ? 519 Support Group 522 Disadvantages 522 The Future 523

X.25 523 An Early Packet-Switching Protocol 523 X.25 and the ISO/OSI 524 Packet Connections 531 Making Connections in a Connectionless World 533 Other Concerns in a Packet-Switched Network 536 Ordering X.25 539 X.25 and Frame Relay 540

Frame Relay 541 Son of ISDN 541 What It Is 541 How It Works 542 Can Your Vendor Do This? 553 The Good News 555 The Bad News 556 Voice and Frame Relay 557 Frame Relay Forum 557

Integrated Services Digital Network 557 The Primordial Mire 557 Anatomy of the ISDN Species 558 It's All in the Packaging 560 ISDN's Function in the Wide Area Food Chain 560 The Goal of Evolution: What These Services Can Provide . . 563 Making ISDN Happen 566 Media 567 The Future: Broadband ISDN 575

Contents

Asynchronous Transfer Mode 576 Digital Subscriber Line Services and Cable Modems 576

Digital Subscriber Line (DSL) 576 Cable Modems 582 DSL vs. Cable Modems 582 Are You Ready to Order? 583

T 21 Purchasing and Managing Wide Area Services 585

Tariffed Services 586 What Is a Tariff? 586 Which Services Are Tariffed? 586 How Do Price Lists Become Tariffs? 587 Who Has Jurisdiction? 587 Why File Tariffs? 588 Bedtime Stories: How to Read a Tariff 589 What Types of WAN Services Are Tariffed? 593

Contract Services 595 Think of It As Buying a Car 595 Size Matters 596 Negotiation Strategies 596 Negotiation Tactics 596

Value-Added Carriers 599 Private Wide Area Networks 599 Public Wide Area Networks 600 Give Us Names! 602

Preparing a Request for Proposals for WAN Service 603 Talking Turkey 603 Step One: Define Your Wide Area Network

Requirements 604 Step Two: Preparing the Outline 604 Step Three: Write Draft Request for Proposals 607 Step Four: Submit Draft RFP for Review and Comment . . . 608 Step Five: Prepare Final Draft of RFP 608 Step Six: Send RFP to Vendors 608 Step Seven: Evaluate Vendor Responses 608 Step Eight: Prepare and Submit Questions to Vendors . . . . 608 Step Nine: Select Vendor 608

Questions for the Finalists 609 Vendor Background Questions 609 Installation Questions 610 Equipment Support Questions 610 Software Support Questions 611 Training Questions 612

Getting What You Pay for: Reviewing the Bills 613 The Importance of Itemization 613

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Bill Reconciliation 613 Managing Wide Area Services 615

Things That Go Wrong 615 Now That We Know What's Broken, Who's Going

to Fix It? 621

T 22 Encryption 623

The Origins of Encryption 624 Encryption Today 624 Encryption in Practice 625

Building the Encrypted Message 625 The Encryption Process * 626 Encryption Algorithms 628

Other Functions of Encryption 633 Personal Encryption Tools 633 Encrypted Web Browsing 635

Speed Considerations 637 Cryptographic Accelerators 637

Problems in Public Key Cryptography 637 Cryptanalysis 638 Poor Password Selection 639 Attacks on Certificate Authorities 639 Key Revocation 640 Cross-Certification 641 Multinational Issues 641 Limitations of Public Key Cryptography 643 User Training 643

Additional Resources 644

T 23 Authentication 645

The Evolution of Computer Authentication 646 Passwords 647 IP Address Authentication 648 Secret Key Cryptography , 648 Public Key Cryptography 650

Public Key Cryptography and Authentication 651 Digital Certificates 652

Certificate Authorities 653 The Roles of the CA . . . , 654 Digital Certificate Issuance 654 Key Management 655 Internal vs. External CAs 656

Public and Private Keys 659 Obtaining a Key Pair 659

Contents

Public Key Derivation 659 Key Length 660 Personal Key Management 660 Public Key Authentication in Practice 661 Key Expiration 663

Advanced Authentication Tools 664 Cryptographic Tokens 664 Smartcards 665 Biometrics 665

• 24 Virtual Private Networking 667

Do You Need a VPN? 668 VPN Paradigms 670 Proper VPN Deployment 672 Introducing Tunneling 673 VPNs and Tunneling Protocols in Practice 673 Authentication with VPNs 677 Encryption with VPNs 679 Another Option: Outsourcing Your VPN 680 Service Level Agreements 682 The Future of Remote Access 682 Other VPN Resources 682

T 25 Unified Messaging 685

Why Has Unified Messaging Taken So Long? 686 Unified Messaging Architectures 687 Telephony Standards and Protocols 692 Implementation Tips 694 What's Next? 695

T Appendix: Keeping It Running 697

Upgrade and Enhancement Projects 698 Hardware Worksheet 698 Service Cost Worksheet 700 Staffing and Staff Development Worksheet 700 Time Estimate Worksheet 701 Applications Worksheet 701 Live Fast, Die Young 701

More Project Pointers 701 First: Try Before You Buy 701 Second: Identify the Next Bottleneck 702 Third: Make a Schedule 702 Fourth: Get Your Budget Approved 703 Fifth: Set Expectations 708

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Surviving 710 Hardware Worksheet 711 Service Cost Worksheet 713 Staff Development Worksheet 714 Staffing Worksheet 715 Time Estimate Worksheet 716 Application Worksheet 718

T Index 719