Networking Essentials

Networking Essentials Companion Guide is the official supplemental textbook for the Networking Essentials course in the Cisco Networking Academy. Networking is at the heart of the digital transformation. The network is essential to many business functions today, including business-critical data and operations, cybersecurity, and so much more. A wide variety of career paths rely on the network, so it's important to understand what the network can do, how it operates, and how to protect it. This is a great course for developers, data scientists, cybersecurity specialists, and other professionals looking to broaden their networking domain knowledge. It's also an excellent launching point for students pursuing a wide range of career pathways-from cybersecurity to software development to business and more. The Companion Guide is designed as a portable desk reference to use anytime, anywhere to reinforce the material from the course and organize your time. The book's features help you focus on important concepts to 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 lists of networking vocabulary introduced and highlighted in context in each chapter. * Glossary: Consult the comprehensive Glossary with more than 250 terms. * Summary of Activities and Labs: Maximize your study time with this complete list of all associated practice exercises at the end of each chapter. * Check Your Understanding: Evaluate your readiness with the end-of-chapter questions that match the style of questions you see in the online course quizzes. The answer key explains each answer.Introduction xxvii Chapter 1 Communications in a Connected World 1 Objectives 1 Key Terms 1 Introduction (1.0) 2 Network Types (1.1) 3 Everything Is Online (1.1.1) 3 Who Owns "The Internet"? (1.1.2) 3 Local Networks (1.1.3) 3 Mobile Devices (1.1.5) 7 Connected Home Devices (1.1.6) 10 Other Connected Devices (1.1.7) 12 Data Transmission (1.2) 15 Types of Personal Data (1.2.2) 15 Common Methods of Data Transmission (1.2.4) 16 Bandwidth and Throughput (1.3) 17 Bandwidth (1.3.1) 17 Throughput (1.3.3) 18 Clients and Servers (1.4) 19 Client and Server Roles (1.4.1) 19 Peer-to-Peer Networks (1.4.2) 20 Peer-to-Peer Applications (1.4.3) 21 Multiple Roles in the Network (1.4.4) 22 Network Components (1.5) 23 Network Infrastructure (1.5.2) 23 End Devices (1.5.3) 25 Summary (1.6) 26 Practice 27 Check Your Understanding 27 Chapter 2 Online Communications 31 Objectives 31 Key Terms 31 Introduction (2.0) 32 Wireless Networks (2.1) 32 Mobile Telephones (2.1.2) 32 Cell Phone Network (2.1.3) 32 Other Wireless Networks (2.1.5) 33 Local Network Connections (2.2) 34 LAN Components (2.2.2) 34 End Device Addressing (2.2.4) 39 Manual and Automatic Address Assignment (2.2.6) 40 Network Documentation (2.3) 41 Device Names and Address Planning (2.3.1) 41 Network Topologies and Representations (2.3.2) 42 Logical Network Information (2.3.4) 43 Summary (2.4) 45 Practice 46 Check Your Understanding Questions 46 Chapter 3 Explore Networks with Packet Tracer 49 Objectives 49 Key Terms 49 Introduction (3.0) 50 Packet Tracer Network Simulator (3.1) 50 Packet Tracer Installation (3.2) 50 The Packet Tracer User Interface (3.3) 51 Locate and Deploy Devices (3.3.2) 52 Packet Tracer Network Configuration (3.4) 53 GUI and CLI Configuration in Packet Tracer (3.4.2) 54 Summary (3.5) 59 Practice 61 Check Your Understanding Questions 61 Chapter 4 Build a Simple Network 67 Objectives 67 Key Terms 67 Introduction (4.0.1) 68 Network Media Types (4.1) 68 Three Media Types (4.1.2) 68 Common Network Cables (4.1.3) 69 Ethernet Cabling (4.2) 71 Twisted-Pair Cables (4.2.1) 71 Types of Twisted-Pair Cables (4.2.2) 72 Coaxial and Fiber-Optic Cabling (4.3) 75 Cable TV and Satellite Cables (4.3.1) 75 Fiber-Optic Cables (4.3.2) 76 Twisted-Pair Operation (4.4) 78 Twisted-Pair Wiring Schemes (4.4.1) 78 Twisted-Pair Transmit and Receive Pairs (4.4.2) 79 Verify Connectivity (4.5) 79 Using the ping Command (4.5.2) 80 The traceroute Command (4.5.3) 81 Summary (4.6) 83 Practice 85 Check Your Understanding Questions 85 Chapter 5 Communication Principles 89 Objectives 89 Key Terms 89 Introduction (5.0.1) 90 The Rules (5.1) 90 The Three Elements (5.1.1) 90 Communication Protocols (5.1.2) 91 Why Protocols Matter (5.1.3) 93 Communication Standards (5.2) 95 The Internet and Standards (5.2.2) 95 Network Standards Organizations (5.2.3) 95 Network Communication Models (5.3) 96 The Protocol Stack (5.3.3) 97 The TCP/IP Model (5.3.4) 98 The OSI Reference Model (5.3.5) 99 Upper and Lower Layers of the OSI Model (5.3.6) 100 OSI Model and TCP/IP Model Comparison (5.3.7) 101 Ethernet (5.4) 103 The Rise of Ethernet (5.4.1) 103 Ethernet Evolution (5.4.2) 104 The Ethernet MAC Address (5.4.4) 105 Summary (5.5) 107 Practice 108 Check Your Understanding Questions 108 Chapter 6 Network Design and the Access Layer 111 Objectives 111 Key Terms 111 Introduction (6.0.1) 112 Encapsulation and the Ethernet Frame (6.1) 112 Encapsulation (6.1.2) 112 Ethernet Frame (6.1.3) 114 Hierarchical Network Design (6.2) 115 Physical and Logical Addresses (6.2.2) 115 Hierarchical Analogy (6.2.5) 117 Benefits of a Hierarchical Design (6.2.7) 117 Access, Distribution, and Core (6.2.8) 119 The Access Layer (6.3) 120 Access Layer Devices (6.3.1) 121 Ethernet Hubs (6.3.2) 121 Ethernet Switches (6.3.4) 123 The MAC Address Table (6.3.6) 124 Broadcast Containment (6.4) 126 Ethernet Broadcasts in the Local Network (6.4.2) 126 Broadcast Domains (6.4.3) 127 Access Layer Communication (6.4.4) 128 ARP (6.4.6) 129 Summary (6.5) 131 Practice 133 Check Your Understanding Questions 133 Chapter 7 Routing Between Networks 137 Objectives 137 Key Terms 137 Introduction (7.0.1) 138 The Need for Routing (7.1) 138 Criteria for Dividing the Local Network (7.1.2) 138 When Routing Is Needed (7.1.3) 141 The Routing Table (7.2) 142 Path Selection (7.2.2) 142 Packet Forwarding (7.2.5) 143 Routing Table Entries (7.2.7) 145 The Default Gateway (7.2.8) 146 Create a LAN (7.3) 147 Local-Area Networks (7.3.1) 147 Local and Remote Network Segments (7.3.2) 148 Summary (7.4) 152 Practice 153 Check Your Understanding Questions 153 Chapter 8 The Internet Protocol 157 Objectives 157 Key Terms 157 Introduction (8.0.1) 158 Purpose of the IPv4 Address (8.1) 158 The IPv4 Address (8.1.1) 158 Binary Conversion of an IPv4 Address (8.2) 159 IPv4 Addressing (8.2.1) 159 Binary to Decimal (8.2.3) 160 The IPv4 Address Structure (8.3) 162 Networks and Hosts (8.3.2) 162 Logical AND (8.3.5) 163 Calculate Whether the Destination Is Local or Remote (8.3.6) 164 Calculate the Number of Hosts (8.3.7) 165 Classful IPv4 Addressing (8.4) 166 Classful and Classless Addressing (8.4.1) 166 Public and Private IPv4 Addresses (8.5) 168 Private IPv4 Addressing (8.5.1) 168 Assignment of IPv4 Addresses (8.5.2) 169 Unicast, Broadcast, and Multicast Addresses (8.6) 171 Unicast Transmission (8.6.2) 171 Broadcast Transmission (8.6.4) 172 Multicast Transmission (8.6.6) 173 Summary (8.7) 175 Practice 177 Check Your Understanding Questions 177 Chapter 9 Dynamic Addressing with DHCP 181 Objectives 181 Key Terms 181 Introduction (9.0.1) 182 Static and Dynamic Addressing (9.1) 182 Static IPv4 Address Assignment (9.1.1) 182 Dynamic IPv4 Address Assignment (9.1.2) 183 DHCP Servers (9.1.3) 184 DHCPv4 Configuration (9.2) 185 DHCPv4 Operation (9.2.2) 185 DHCP Service Configuration (9.2.4) 186 Summary (9.3) 188 Practice 189 Check Your Understanding Questions 189 Chapter 10 IPv4 and IPv6 Address Management 193 Objectives 193 Key Terms 193 Introduction (10.0.1) 194 Network Boundaries (10.1) 194 Routers as Gateways (10.1.2) 194 Routers as Boundaries Between Networks (10.1.3) 195 Network Address Translation (10.2) 196 NAT Operation (10.2.2) 196 IPv4 Issues (10.3) 198 Need for IPv6 (10.3.1) 198 IPv6 Address Size (10.3.2) 200 IPv4 and IPv6 Coexistence (10.3.4) 201 IPv6 Features (10.4) 203 IPv6 Autoconfiguration and Link-Local Addresses (10.4.3) 203 IPv6 Address Representation (10.4.5) 204 Summary (10.5) 206 Practice 207 Check Your Understanding Questions 208 Chapter 11 Transport Layer Services 211 Objectives 211 Key Terms 211 Introduction (11.0.1) 212 The Client/Server Relationship (11.1) 212 Client and Server Interaction (11.1.1) 212 Client Requests a Web Page (11.1.3) 213 URI, URN, and URL (11.1.4) 214 TCP and UDP (11.2) 215 Protocol Operations (11.2.1) 215 TCP and UDP (11.2.3) 216 TCP Reliability (11.2.4) 216 UDP Best Effort Delivery (11.2.5) 217 Port Numbers (11.3) 218 TCP and UDP Port Numbers (11.3.2) 218 Destination and Source Port Numbers (11.3.3) 220 Socket Pairs (11.3.4) 221 The netstat Command (11.3.5) 223 Summary (11.4) 224 Practice 225 Check Your Understanding Questions 225 Chapter 12 Application Layer Services 229 Objectives 229 Key Terms 229 Introduction (12.0.1) 230 Network Application Services (12.1) 230 Common Network Application Services (12.1.1) 230 Domain Name System (12.2) 231 Domain Name Translation (12.2.1) 231 DNS Servers (12.2.3) 232 Web Clients and Servers (12.3) 233 HTTP and HTML (12.3.2) 233 FTP Clients and Servers (12.4) 234 File Transfer Protocol (12.4.1) 235 FTP Client Software (12.4.3) 236 Virtual Terminals (12.5) 237 Telnet (12.5.2) 237 Security Issues with Telnet (12.5.3) 238 Email and Messaging (12.6) 239 Email Clients and Servers (12.6.1) 239 Email Protocols (12.6.2) 240 Text Messaging (12.6.3) 242 Internet Phone Calls (12.6.4) 243 Summary (12.7) 244 Practice 246 Check Your Understanding Questions 246 Chapter 13 Build a Home Network 249 Objectives 249 Key Terms 249 Introduction (13.0.1) 250 Home Network Basics (13.1) 250 Connecting Home Devices (13.1.1) 250 Components of a Home Network (13.1.2) 251 Typical Home Network Routers (13.1.3) 252 Network Technologies in the Home (13.2) 253 The Electromagnetic Spectrum (13.2.1) 253 LAN Wireless Frequencies (13.2.2) 254 Wired Network Technologies (13.2.3) 255 Wireless Standards (13.3) 257 Wi-Fi Networks (13.3.1) 257 Wireless Settings (13.3.2) 257 Wireless Traffic Controls (13.4) 259 Wireless Channels (13.4.1) 259 Wireless as a Shared Media (13.4.2) 260 Set Up a Home Router (13.5) 261 First Time Setup (13.5.1) 261 Design Considerations (13.5.2) 261 MAC Address Filtering (13.5.3) 263 Summary (13.6) 265 Practice 267 Check Your Understanding Questions 267 Chapter 14 Connect to the Internet 271 Objectives 271 Key Terms 271 Introduction (14.0.1) 272 ISP Connectivity Options (14.1) 272 ISP Services (14.1.1) 272 ISP Connections (14.1.2) 273 Cable and DSL Connections (14.1.3) 274 Additional Connectivity Options (14.1.4) 275 Network Virtualization (14.2) 276 Cloud Computing (14.2.2) 276 Types of Clouds (14.2.3) 276 Cloud Services (14.2.4) 277 Cloud Computing and Virtualization (14.2.5) 277 Advantages of Virtualization (14.2.6) 279 Hypervisors (14.2.7) 279 Network Virtualization (14.2.9) 281 Control Plane and Data Plane (14.2.10) 282 Network Virtualization and SDN (14.2.11) 283 SDN Architecture (14.2.12) 283 Mobile Device Connectivity (14.3) 284 Mobile Devices and Wi-Fi (14.3.1) 284 Wi-Fi Settings (14.3.2) 285 Configure Mobile Wi-Fi Connectivity (14.3.3) 286 Configure Cellular Data Settings (14.3.4) 288 Simple Connectivity with Bluetooth (14.3.6) 290 Bluetooth Pairing (14.3.7) 290 Summary (14.4) 293 Practice 295 Check Your Understanding Questions 295 Chapter 15 Security Considerations 299 Objectives 299 Key Terms 299 Introduction (15.0.1) 300 Security Threats (15.1) 300 Types of Threats (15.1.1) 300 Internal and External Threats (15.1.2) 301 Social Engineering Attacks (15.2) 302 Overview of Social Engineering (15.2.1) 302 Types of Social Engineering Attacks (15.2.2) 303 Malware (15.3) 304 Malicious Software (15.3.1) 305 Types of Malware (15.3.2) 305 Spyware (15.3.3) 306 Adware and Popups (15.3.4) 306 Botnets and Zombies (15.3.5) 307 Denial-of-Service Attacks (15.4) 308 Denial of Service (15.4.1) 308 Distributed Denial of Service (15.4.2) 309 Brute Force (15.4.3) 310 Security Tools (15.5) 310 Security Practices and Procedures (15.5.1) 310 Security Tools and Applications (15.5.2) 312 Patches and Updates (15.5.3) 313 Antimalware Software (15.6) 314 Signs of Infections (15.6.1) 314 Antivirus Software (15.6.2) 315 Antispam Software (15.6.3) 316 Antispyware Software (15.6.4) 316 Additional Safeguards (15.6.5) 317 Summary (15.7) 318 Practice 321 Check Your Understanding Questions 321 Chapter 16 Configure Network and Device Security 325 Objectives 325 Key Terms 325 Introduction (16.0.1) 326 Wireless Security Measures (16.1) 326 Wireless Vulnerabilities (16.1.1) 326 A Comprehensive Security Plan (16.1.2) 327 SSID Broadcasts (16.1.4) 333 Changing Default Settings (16.1.5) 334 MAC Address Filtering (16.1.6) 335 Implement Wireless Security (16.2) 336 Open Authentication (16.2.1) 336 Authentication and Association (16.2.2) 336 Authentication Protocols (16.2.3) 337 Configure a Firewall (16.3) 338 Firewall Overview (16.3.1) 338 Firewall Operation (16.3.2) 338 The DMZ (16.3.3) 339 Port Forwarding (16.3.4) 340 Port Triggering (16.3.5) 341 Summary (16.4) 344 Practice 345 Check Your Understanding Questions 346 Chapter 17 Cisco Switches and Routers 349 Objectives 349 Key Terms 349 Introduction (17.0.1) 350 Cisco Switches (17.1) 350 Connect More Devices (17.1.1) 350 Cisco LAN Switches (17.1.2) 351 LAN Switch Components (17.1.5) 354 Switch Boot Process (17.2) 355 Power Up the Switch (17.2.1) 355 In-Band and Out-of-Band Management (17.2.3) 358 IOS Startup Files (17.2.4) 358 Cisco Routers (17.3) 359 Router Components (17.3.2) 360 Router Interface Ports (17.3.3) 360 Router Boot Process (17.4) 361 Power Up the Router (17.4.1) 361 Management Ports (17.4.2) 365 Summary (17.5) 367 Practice 368 Check Your Understanding Questions 368 Chapter 18 The Cisco IOS Command Line 373 Objectives 373 Key Terms 373 Introduction (18.0.1) 374 Navigate the IOS (18.1) 374 The Cisco IOS Command-Line Interface (18.1.1) 374 Primary Command Modes (18.1.2) 375 A Note About Syntax Checker Activities (18.1.5) 376 The Command Structure (18.2) 376 Basic IOS Command Structure (18.2.1) 376 IOS Command Syntax (18.2.2) 377 Hotkeys and Shortcuts (18.2.4) 378 View Device Information (18.3) 380 Show Commands (18.3.2) 381 Summary (18.4) 387 Practice 388 Check Your Understanding Questions 388 Chapter 19 Build a Small Cisco Network 391 Objectives 391 Key Terms 391 Introduction (19.0.1) 392 Basic Switch Configuration (19.1) 392 Basic Switch Configuration Steps (19.1.1) 392 Switch Virtual Interface Configuration (19.1.2) 394 Configure Initial Router Settings (19.2) 395 Basic Router Configuration Steps (19.2.1) 395 Basic Router Configuration Example (19.2.2) 396 Secure the Devices (19.3) 398 Password Recommendations (19.3.1) 398 Secure Remote Access (19.3.2) 399 Configure SSH (19.3.3) 400 Verify SSH (19.3.5) 402 Connecting the Switch to the Router (19.4) 404 Default Gateway for a Host (19.4.1) 404 Default Gateway on a Switch (19.4.2) 406 Summary (19.5) 409 Practice 411 Check Your Understanding Questions 412 Chapter 20 Troubleshoot Common Network Problems 415 Objectives 415 Key Terms 415 Introduction (20.0.1) 416 The Troubleshooting Process (20.1) 416 Network Troubleshooting Overview (20.1.1) 416 Gather Information (20.1.2) 416 Structured Troubleshooting Methods (20.1.3) 418 Guidelines for Selecting a Troubleshooting Method (20.1.4) 422 Physical Layer Problems (20.2) 423 Common Layer 1 Problems (20.2.1) 423 Wireless Router LEDs (20.2.2) 424 Cabling Problems (20.2.3) 426 Troubleshooting Commands (20.3) 426 Overview of Troubleshooting Commands (20.3.1) 426 The ipconfig Command (20.3.2) 427 The ping Command (20.3.4) 430 Ping Results (20.3.5) 431 Divide and Conquer with ping (20.3.7) 432 The tracert Command (20.3.8) 433 The netstat Command (20.3.9) 434 The nslookup Command (20.3.10) 436 Troubleshoot Wireless Issues (20.4) 438 Causes of Wireless Issues (20.4.1) 438 Authentication and Association Errors (20.4.2) 439 Common Internet Connectivity Issues (20.5) 441 DHCP Server Configuration Errors (20.5.1) 441 Check Internet Configuration (20.5.2) 442 Check Firewall Settings (20.5.3) 444 Customer Support (20.6) 444 Sources of Help (20.6.1) 445 When to Call for Help (20.6.2) 445 Support Desk Interaction (20.6.3) 446 Issue Resolution (20.6.4) 447 Support Desk Tickets and Work Orders (20.6.5) 448 Summary (20.7) 450 Practice 453 Check Your Understanding Questions 454 Appendix A Answers to the "Check Your Understanding" Questions 459 Glossary 471 9780137660483 TOC 1/25/2022Cisco Networking Academy is an innovative Cisco education initiative that delivers information and communication technology skills to improve career and economic opportunities around the world. The Academy provides online courses, interactive tools, and lab activities to prepare individuals for information technology and networking careers in virtually every industry.