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Part 1 Fundamentals3

1 Basic Concepts3

Analog and Digital5

Analog Signals6

Digital Signals7

Bauds, Bits, Bytes and Codes—Getting Down to Basics13

Overview13

Baud Rate vs. Bits per Second—Electrical Signal Rates vs. Amount of Information Sent13

Codes—Adding Meaning to Bits14

A Byte=A Character15

Bandwidth—Measuring Capacity15

Narrowband vs. Wideband—Slow and Fast16

Compression and Multiplexing17

Compression—Manipulating Data for More Capacity18

Streaming Media20

Multiplexing—Let s Share23

Protocols and Architectures25

Architectures—A Framework for Multiple Networks to Communicate26

LANs, MANs and WANs28

LANs—Local Area Networks30

LAN and WAN Devices31

Home LANs—Sharing Printers and High-Speed Internet Access—A Lack of Technical Support36

MANs—Metropolitan Area Networks38

WANs—Wide Area Networks38

Higher Speed Services for LAN Traffic38

New Devices for Carrier and Internet Service Provider Networks39

2 Telephone Systems, Peripherals and Cabling45

Telephone Systems—PBXs, Centrex and Key Systems47

What Is a PBX?47

PBX Trunks48

Demarcation—The Location Where Telcos Wire Trunks48

PBX Telephones49

Centrex—Telephone Company Supplied Service50

Key Systems53

Wireless PBX and Key System Telephones—On-Site Mobility53

Direct-Inward Dialing—Bypassing the Operator for Incoming Calls57

Convergence and Telephone Systems58

Add-on Peripherals for Key Systems, PBXs and Centrex Systems63

Call Accounting—Tracking Calls and Usage64

ACDs—Specialized Equipment to Handle Large Volumes of Calls72

Network-Based ACD Functions73

LAN/PBX/ACD Connectivity to Enhance Productivity74

Customer Relationship Management(CRM) for Call Centers74

Integrated Voice Response Units—Using the Telephone as a Computer Terminal76

Computer Telephony Integration(CTI)—Routing Callers More Intelligently79

Media: Wireless, Fiber and Unshielded Twisted Pair Copper80

Wireless LANs81

Electrical Properties of Copper Cabling83

Fiber Optic Cabling—High Capacity and High Costs84

Part 2 Industry Overview93

3 The Bell System and Regulatory Affairs93

The Bell System Prior to and after 198495

Divestiture of the Bell System from AT&T in 198495

Regional Bell Operating Companies(RBOCs) after 199698

Transporting Calls Between Carriers101

Local Competition Prior to the Telecommunications Act of 1996103

Uneven Competition for Local Telephone Service Throughout the U.S.103

Competitive Access Providers(CAPs) to Competitive Local Exchange Carriers(CLECs)103

The Evolving View of the Feasibility of Local Competition107

Factors Leading to Passage of the Telecommunications Act of 1996108

Regional Bell Companies Desire to Expand Their Offerings108

Interexchange Carriers ,Utility and Cable TV Companies Desires to Enter New Markets108

Demand for High-Speed Telecommunications Services109

Technological Capabilities to Provide High-Speed Services at Low Costs109

The Viability of Wireless Services for Local Exchange Service109

The Desire for a Uniform National Policy on Local Competition110

The Telecommunications Act of 1996110

Major Features of the Act111

Post Telecommunications Act of 1996 Developments117

FCC Rulings, Legal Challenges and Progress Toward Deregulation117

Permission for RBOCs to Sell In-Region Long Distance118

Unbundled Network Elements(UNEs)—Competitors Leasing Parts of RBOCs Networks120

Fines Levied on Incumbents for Failure to Provide Timely Access to Competitors121

Reciprocal Payments121

Local Access Fees—A Shift in Balance Between Local and Long Distance Costs122

Local Number Portability123

Creating an Equal Playing Field and Conserving Numbers123

Four Types of Telephone Number Portability123

Impact of the Telecommunications Act of 1996127

Appendix129

4 Network Service Providers and Local Competition135

Local Competition137

Strategies for Entering the Local Calling Market—Resale, Wireless,Cable TV and Construction of Facilities148

Carriers155

Interexchange Carriers—IEXs156

Bandwidth Trading:The Commoditization of Bandwidth158

Merchants—Managing Risk for Carriers159

Exchanges—A Place to Make Trades160

Master Trading Agreements—Shortening the Transaction Cycle161

Local Service Providers161

AT&T161

Competitive Local Exchange Carriers(Integrated Communications Providers)163

Resellers and Switchless Resellers167

Building Local Exchange Carriers(BLECs)169

Agents170

Summary173

5 The Public Network175

Switched Services—Local and Long Distance Calling177

Attributes of Real-Time Switching Services178

DTMF: Access to Voice Mail and Computers183

Store-and-Forward Switching—Nonsimultaneous Sending and Receiving184

Dedicated Services184

Overview of Dedicated Services185

Network Topologies—The View from the Top188

Declining Sales of Private Lines192

Virtual Private Networks—Connectivity for Remote Access,Intranets and Extranets193

VPNs(Virtual Private Networks) for Electronic Commerce194

VPNs for Intranet Service194

Virtual Private Networks(VPNs) for Remote Access195

Security on Virtual Private Networks196

The Last Mile or Access Networks197

End and Tandem Central Offices199

Digital Loop Carrier Systems—Fiber Optics and Copper Cabling in the Last Mile201

Carrier Hotels—Interconnecting Carriers and Providing Secure Space for Equipment202

Optical Networking203

Passive Optical Networks204

Optical Add and Drop Multiplexers(OADM)207

Optical Cross Connects(OXC)—Optical Switches208

Network Intelligence and Signaling212

Overview of Signaling213

Background215

Common Channel Signaling, Efficiency and Redundancy218

Signaling System 7—The Glue for Links Between Carriers218

SS7 Components220

Convergence—Technical Advances Leading to Improvements in IP Networks221

Improvements in Routers222

Digital Signal Processors(DSPs)223

Voice Compression224

Higher Capacity Networks—Optical Technologies224

Softswitches—Programmable Switches225

The Quality of Service Issue for Voice over IP227

SS7 in Packet Networks228

Examples of Converged Networks229

Free Calls or Low Priced Calls over the Internet231

H.323—A Way to Make Telephone Calls over IP232

Prepaid Calls over the Internet232

Document Sharing and Click to Talk233

Document Sharing233

Summary235

Part 3 Advanced Technologies,The Internet and Wireless239

6 Specialized Network Services239

T-1—24 Voice or Data Paths over One Telephone Circuit243

Channel Banks—Connecting T-1 to Analog PBXs and Central Offices244

DS-O and DS-1—64,000 or 56,000 vs. 1,544,000 bps244

Media Used for T-1 Signals245

European vs. American and Japanese T-1—24 vs. 30 Channels246

A Sampling of T-1 Configurations Using T-1 for Combining Voice, Fax,Video and Data247

Fractional T-1—When 24 Paths Are Not Required248

T-3—The Capacity of 28 T-1 Lines, 672 Channels249

An Explanation of Time Division Multiplexing and Its Limitations249

ISDN—Integrated Services Digital Network250

Basic Rate Interface ISDN—Two Channels at 64,000 Bit per Second253

Primary Rate Interface ISDN—24 Channels254

Digital Subscriber Line Technology257

Competitive Iocal exchange carriers(CLECs) and DSL261

Incumbent Telephone Company DSL Offerings262

DSLAMs—Digital Subscriber Line Access Multiplexers262

Obstacles to Digital Subscriber Line Availability—Cost, Ease of Implementation and Availability263

DSL Lite—Lower Cost Service266

DSL—A Technical Explanation266

Frame Relay—A Shared Wide Area Network Service267

Connections to Frame Relay—Frame Relay Access Devices and Access Line Speeds269

Frame Relay for Transmitting Voice270

Frame Relay Pricing—Ports, Circuits and Committed Information Rate270

Potential Congestion on Frame Relay271

Interfacing Between Carriers Frame Relay Networks271

Gigabit Ethernet—Ethernet over Fiber in Metropolitan Areas271

Gigabit Ethernet Providers—OLECs272

Gigabit Ethernet Through Partners273

Gigabit Ethernet Availability273

The Advantages of Using Ethernet273

Speed Options—Bandwidth on Demand274

Gigabit Ethernet Features at Lower Prices275

A Sample Metropolitan Area Gigabit Ethernet Configuration275

ATM—Asynchronous Transfer Mode276

Fixed-Sized Cells—Less Processing278

Switching in Hardware—Less Address Lookup278

Asynchronous Switching—Improving Network Utilization278

Bursting—Selling More Than the Total Capacity279

Scalability—The Ability to Use ATM for High-and Low-Speed Applications and IP Traffic279

Elements of an ATM Network280

SONET—Synchronous Optical Network283

Synchronous Digital Hierarchy(SDH) and SONET284

SONET Functions—The Four Layers285

SONET Rings—For Greater Reliability286

Telephone Company SONET Offerings287

SONET Connections to Wave Division Multiplexers288

Meshed Optical Technology—Lower Costs, More Suitable for Data than SONET289

7 Analog, Cable TV and Digital Modems and Set-Top Boxes291

Transferring Data from Computers to Telephone Lines292

DCE—Connections to Telephone Lines294

Modems—Analog Telephone Lines for Transmitting Data from Digital Devices295

Fax Modems296

56-Kbps Modems to Achieve Higher Speeds296

PCMCIA Modems—Smaller Is Better299

NTIS—CONNECTING DEVICES TO AN ISDN LINE299

CSU/DSUs—Connecting Devices to a Digital Line300

Cable Modems—Using Cable TV Facilities for Data Communications301

Reverse Channels for Two-Way Data Communications302

Cable Modems302

Cable Modems for Business and for Remote Access305

Set-Top Boxes307

Interoperable Set-Top Boxes308

Digital Cable TV310

Appendix: Modem Standards311

8 The Internet315

The History of the Internet317

Bulletin Board Systems(BBSs)319

Who Runs the Internet?319

Who Owns the Internet?320

Peering—A Way to Exchange Data Between Networks320

Content Delivery Networks(CDNs) and Caching—Solving the Problem of Bogged-Down Web Sites321

Internet Services322

The World Wide Web—Linking and Graphics323

Hypertext Markup Language(HTML)—Formatting Web Pages324

Home Pages325

Hosting—Computers Connected to the Internet With Home Pages327

Browsers—Moving from Web Site to Web Site328

Email—Computers that Send, Store and Receive Messages330

Email Attachments—To Aid Collaborative Projects331

HTML Email as a Marketing Tool332

Instant Messaging—Real-Time Text Chats333

Internet Service Providers, Application Service Providers and Portals335

Dialup and Dedicated Internet Access336

Application Service Providers(ASPs)338

Portals—Content as Well as Internet Access338

Search Engines342

Internet Addresses346

Registries—Management of Entire Top-Level Domains346

Registrars347

Numeric IP Addresses347

The Structure of Internet Addresses and Adding Capacity for More Addresses347

New Generic Top-Level Domains(gTLDs)348

Country Code Top-Level Domain Names(ccTLDs)349

Electronic Commerce and Advertising on the Web349

Advertising on the Web—A Source of Revenue350

Online Commerce—What Is Profitable and Sells?351

Privacy on the World Wide Web354

Opt-out vs. Opt-in—Different Approaches to Protecting Privacy356

Legal Issues357

Post-Napster Music Industry Online Efforts358

The Digital Millennium Copyright Act(DMCA)—Royalties for Radio over the Internet359

Anti-pornography Laws and Freedom of Speech359

Filtering Software—Policing Corporate Browsing and Email361

Open Cable—Cable Companies as Both ISPs and Network Service Providers361

ISP Service for Cable TV361

Open Cable Service—Trialing Connections to Other IPS362

Intranets and Extranets365

Intranets—lmpact of Web Technology on Internal Operations365

Extranets—Using Internet Technology With Customers, Partners and Vendors366

Security on the World Wide Web—Establishing Trust367

Public and Private Keys and Digital Certificates368

Firewalls and Tunneling368

Making the Internet a Trusted Place to Do Business369

Conclusion370

9 Wireless Services371

Historical Background of Mobile and Cellular Services376

Spectrum Allocation377

Spectrum for Higher Speed 3G Services378

Cellular Telephone Service—Technologies379

Advanced Mobile Phone Services(AMPS)379

Digital-Advanced Mobile Phone Service—D-AMPS380

PCS—Personal Communications Services381

GSM Service382

Specialized Mobile Frequencies for Voice—Nextel383

Cellular Vendors384

Verizon Wireless384

Cingular Wireless384

AT&T Wireless385

GSM Providers385

Sprint PCS386

The Structure of Cellular Networks386

The Cellular Market387

Efforts to Improve Service—Antenna Improvements389

Health Concerns390

Safety on the Road391

Privacy and Advertising Intrusions on Cellular E911394

Called Party Pays—An Impediment to Cellular Usage395

Limited Mobility Wireless for Local Telephone Service397

Wireless Number Portability—Keeping the Same Number When Changing Carriers398

Limitations of Circuit-Switched Cellular for Data Communications398

CDPD—Cellular Digital Packet Data, IP Wireless398

The Transition from Second to Third Generation Cellular Networks399

The Transition to W-CDMA-GPRS—Data Carried as Packets in 2.5G Networks401

EDGE-Enhanced Data Rates for GSM Evolution402

Upgrades to W-CDMA from GSM—Costly402

The Transition to cdma2000—1xRTT(First Generation cdma2000) and HDR (High Data Rate)403

A Comparison Between W-CDMA and cdma2000404

Handsets for 3G and 2.5G Services405

All-Packet Cellular Networks for Voice and Data406

4G—Futures406

Mobile Internet Access, Messaging Services and Bluetooth406

Mobile Commerce407

Short Messaging Service(SMS)407

Bluetooth408

The Wireless Application Protocol(WAP)408

i-mode Service Worldwide409

Specialized Mobile Radio—Originally Voice, Later Data409

Private Networks over Mobile Radio Frequencies410

Specialized Mobile Radio—Packetized Data Networks for Two-Way Email and Field Services410

Paging Services411

Paging vs. Wireless Telephone Service412

Two-Way Paging Using Narrowband PCS412

Satellites413

VSAT Service—Small Satellite Dishes414

Vendors of LEOs416

Time Division Multiple Access, GSM and Code Division Multiple Access Air Interfaces416

Code Division Multiple Access418

Time Division Multiple Access and GSM418

10 Globalization419

The Impetus to Deregulate421

Steps in Deregulation421

Challenges422

Trends in Global Markets422

Latin America424

Brazil424

Mexico429

Argentina430

Impact of Poverty433

Asia437

China437

Japan442

The Internet449

Cellular Service450

Europe453

The European Union453

Cellular Service455

Germany457

The United Kingdom460

France462

Africa and the Middle East—Emerging Markets471

Africa472

The Middle East472

Conclusion473

Glossary475

Bibliography487

Index489