net Offers Flexibility and Scalable Speeds 244 Carrier Ethernet over Copper in the First Mile 244 Contents T1 and T3: The First Broadband Services for Businesses A Comparison of T1 and E1 247 A Comparison of T3, J3, and E3 Worldwide Standards T1 and the Inefficiencies of Time-Division Multiplexing Channel Service Units and Digital Service Units 249 Private Lines, Network Topology, and Frame Relay The Costly Solution of Dedicated Private Lines 250 Network Topologies 252 Integrated Services Digital Network 254 Frame Relay 256 Appendix 257 6 The Internet Introduction The Growth of the Internet 264 Using Search Engines to Unleash Vast Stores of Information 265 Competition from Social Networks 265 Internet Access via Mobile Devices 266 The Impact of Video 266 The Structure of the Internet 267 Edge Routers Core, Aggregation Routers 269 Ensuring Reliability in the Core and Edge 270 Enhancing Internet Performance by Using Content Delivery Networks 270 Exchanging Data at Peering Points 271 Address Structures 272 The 13 Root Servers Worldwide 273 Tracking and Managing Top-Level Domain Names 273 Security Threats from Internal, External, and International Sources 274 Cyber Terrorism Attacks on Enterprises 275 Intentional and Inadvertent Security Breaches by Insiders 277 Privacy 278 Privacy versus the Bottom Line 279 The Stricter European Privacy Rules 280 Contents Video Streamed from the Internet to the Front Room 280 Cultural, Economic, and Technological Factors 281 Over-the-Top Competitors versus Cable Operators The Quest for Current, Quality Content 283 Technical Challenges 285 Electronic Commerce 286 The Attraction of Online Services 287 Online Community Forums 290 Town E-mail Lists Can Keep Communities Informed 291 Community Wikis 292 Network Neutrality Background Events Open Internet Regulations 296 The Digital Divide: Bandwidth, Skills, and Computers 297 Intranets and Extranets 298 Intranets 299 Extranets 300 Summary 301 Part IV Mobile Networks and Mobile Carriers Worldwide 7 Mobile and Wi-Fi Networks Introduction 306