CompTIA Network+ Cert Guide with myITcertificationlabs Bundle (N10-004)

Book:

 

Introduction 3

How This Book Helps You 4

  Exam Objectives and Chapter Organization 4

Instructional Features 18

Network Hardware and Software Requirements 19

Advice on Taking the Exam 20

Chapter 1 Introduction to Computer Networking 23

What Is a Network? 24

LANs and WANs 25

Peer-to-Peer Versus Client/Server Networks 28

  The Peer-to-Peer Networking Model 28

  Advantages of Peer-to-Peer Networks 29

  Disadvantages of Peer-to-Peer Networks 30

  The Client/Server Networking Model 30

  Servers 31

  Client Computers 32

  Advantages of Client/Server Networking 32

  Disadvantages of Client/Server Networking 32

  Distributed and Centralized Computing 33

Virtual Private Networks (VPN) 34

  Components of the VPN Connection 35

  VPN Pros and Cons 35

Virtual Local Area Network (VLAN) 36

  VLAN Membership 37

  Protocol-Based VLANs 37

  Port-Based VLANs 38

  MAC Address-Based VLANs 38

  VLAN Segmentation 39

LAN Topologies 40

  Physical and Logical Topologies 41

  Bus Topology 41

  Star Topology 42

  Ring Topology 44

  Wired Mesh Topology 45

Wireless Network Topologies 47

  Infrastructure Wireless Topology 47

  Ad Hoc Wireless Networking 48

  Point-to-Point, Point-to–Multipoint, and Mesh-Wireless Topology 48

  Point-to-Point Networks 48

  Point-to-Multipoint 50

  Mesh Networks 50

  Hybrid Topologies 51

Summary 52

Chapter 2 Media and Connectors 61

Networking Media 62

  Media Interference 62

  Data Transmission Rates 63

  Media Length 63

Secure Transmission and Physical Media 64

  Installation and Repair 65

  Simplex, Half-Duplex, and Full-Duplex 65

  Cable Media 66

  Twisted-Pair Cable 67

  Coaxial Cable 69

  Fiber-Optic Cable 70

Media Connectors 72

  RJ Connectors 72

  F-Type Connectors and RG-59/RG-6 Cables 73

  RS-232 Standard 74

  Fiber Connectors 74

  IEEE 1394 (FireWire) 75

  Universal Serial Bus Connectors (USB) 76

  Cable Summary 76

Wiring Standards and Specialized Cable 77

  568A and 568B Wiring Standards 77

  Straight Versus Crossover Cable 78

  Rollover and Loopback Cables 80

Components of Wiring Distribution 80

  Network Cross Connects 81

  Horizontal Cabling 81

  Vertical Cable 82

  Patch Panels 83

  Type 66 and Type 110 Punchdown Blocks 84

  MDF and IDF 85

  Demarcation Point 86

  Verify Wiring Installation and Termination 87

Summary 89

Chapter 3 Networking Components and Devices 99

Common Network Devices 100

  Hubs 100

  Network Switches 102

  Switching Methods 105

  Advanced Switch Features 105

  Power over Ethernet (PoE) 106

  Trunking 106

  Port Authentication 107

  Working with Hubs and Switches 107

  Hub and Switch Ports 107

  Hub and Switch Indicator Lights 109

  Rack-Mount, Stackable, and Freestanding Devices 109

  Managed Hubs and Switches 109

  Repeaters 110

  Bridges 110

  Bridge Implementation Considerations 111

  Types of Bridges 114

  Routers 114

  Gateways 117

  Modems 118

  Modem Connection Speeds 119

  Network Interface Cards (NIC) 120

  Types of Network Interfaces 121

  Installing Network Cards 123

  Media Converters 124

  Firewalls 125

  DHCP Server 126

Specialized Network Devices 127

  Multilayer and Content Switches 127

  Intrusion Detection and Prevention Systems 128

  Load Balancer 129

  Multifunction Network Devices 129

  DNS Server 129

  Bandwidth Shaper 130

  Proxy Server 131

  CSUs/DSUs 133

  Network Devices Summary 134

Summary 136

Chapter 4 Understanding the TCP/IP Protocol Suite 145

A Brief Introduction to Protocols 146

  Protocols from the Sending Device 147

 Protocols on the Receiving Device 147

Transmission Control Protocol/Internet Protocol (TCP/IP) Protocol Suite 148

  Internet Protocol (IP) 149

  Transmission Control Protocol (TCP) 149

  User Datagram Protocol (UDP) 150

  File Transfer Protocol (FTP) 151

  Secure Shell (SSH) 152

  Secure File Transfer Protocol (SFTP) 152

  Trivial File Transfer Protocol (TFTP) 153

  Simple Mail Transfer Protocol (SMTP) 153

  Hypertext Transfer Protocol (HTTP) 154

  Hypertext Transfer Protocol Secure (HTTPS) 154

  Post Office Protocol Version 3/Internet Message Access Protocol Version 4 (POP3/IMAP4) 155

  Telnet 155

  Internet Control Message Protocol (ICMP) 156

  Address Resolution Protocol (ARP) and Reverse Address Resolution Protocol

  (RARP) 156

  Network Time Protocol (NTP) 157

  Network News Transfer Protocol (NNTP) 157

  Secure Copy Protocol (SCP) 158

  Lightweight Directory Access Protocol (LDAP) 158

  Internet Group Management Protocol (IGMP) 158

  Domain Name System (DNS) 159

  The DNS Namespace 160

  Types of DNS Entries 162

  DNS in a Practical Implementation 163

  Simple Network Management Protocol (SNMP) 163

     Components of SNMP 164

  SNMP Management Systems 164

  SNMP Agents 165

  Management Information Bases (MIB) 165

  SNMP Communities 166

  Dynamic Host Configuration Protocol (DHCP) 167

  Transport Layer Security 170

  Session Initiation Protocol 170

  Real-time Transport Protocol (RTP) 171

  TCP/IP Protocol Suite Summary 171

Identifying Common TCP/IP Port Numbers 173

Summary 175

Chapter 5 TCP/IP Addressing and Routing 185

Identifying MAC Addresses 186

Understanding IPv4 Addressing Fundamentals 187

  General IP Addressing Principles 188

  IPv4 Addressing 188

  IPv4 Address Types 190

  Distributing IPv4 Addresses to the Network 191

  Static Addressing 191

  Dynamic Addressing 191

  Bootstrap Protocol (BOOTP) 191

  APIPA and IPv4 192

  Broadcast Addresses and “This Network” 193

  Classless Interdomain Routing (CIDR) 193

  Default Gateways 194

Understanding Subnetting 195

Public and Private IP Address Schemes 198

  Private Address Ranges 199

  Practical Uses of Public and Private IP Addressing 200

IPv6 Addressing 201

  Identifying IPv6 Addresses 201

  IPv6 Address Types 202

Differentiating Between Routable and Routing Protocols 204

  Routable Protocols 204

  Routing Protocols 205

  Distance-Vector Routing Protocols 206

  Link-State Routing Protocols 208

NAT, PAT, and SNAT 209

Summary 211

Chapter 6 Ethernet Networking Standards 221

Characteristics Specified in the IEEE 802 Standards 223

  Speed 223

  Access Methods 223

  Carrier Sense Multiple Access/Collision Detection 224

  CSMA/CA 225

  Token Passing 226

  Bonding 226

  Topology 226

  Media 227

Differentiating Between Baseband and Broadband Signaling 227

  Baseband 227

  Broadband 227

Ethernet Standards 228

  10Base2 228

  10BaseT 229

  10BaseFL 230

  Fast Ethernet 230

  100BaseTX 231

  100BaseT4 231

  100BaseFX 231

  Fast Ethernet Comparison 231

  Gigabit Ethernet 232

  1000BaseX 232

  1000BaseT 233

  10Gigabit Ethernet 234

  10GBaseSR/SW 234

  10GBaseLR/LW 235

  10GBaseER/EW 235

  10GBaseT 236

Summary 236

Chapter 7 Wireless Networking 245

Understanding Wireless Devices 246

  Wireless Access Point 246

  Wireless Antennas 248

  Antenna Ratings 249

  Types of Wireless Antennas 249

802.11 Wireless Standards 251

  The Magic Behind 802.11n 254

  Wireless Radio Channels 254

Spread Spectrum Technology 257

  Frequency-Hopping Spread Spectrum (FHSS) Technology 257

  Direct-Sequence Spread Spectrum (DSSS) Technology 258

  Orthogonal Frequency Division Multiplexing 258

  FHSS, DSSS, OFDM, and 802.11 Standards 258

Beacon Management Frame 259

Configuring and Troubleshooting the Wireless Connection 260

  Configuring Communications Between Wireless Devices 262

  Troubleshooting Wireless Signals 264

  Site Surveys 265

  Troubleshooting AP Coverage 266

  Wireless Troubleshooting Checklist 267

Securing Wireless Networks 268

  Defining Access Control, Authentication, Authorization, and Encryption 268

  Wireless Authentication and Encryption Methods 269

  Wired Equivalent Privacy (WEP) 270

  Wi-Fi Protected Access (WPA) 270

  Temporal Key Integrity Protocol (TKIP) 271

     802.1X 272

  Securing the Access Point 273

Summary 273

Chapter 8 Wide Area Networking 283

Public and Private Networks 284

  Public Networks 284

  Public Switched Telephone Network (PSTN) 284

  The Internet 285

  Advantages and Disadvantages of Public Networks 286

  Private Networks 286

Switching Methods 287

  Packet Switching 288

  Virtual-Circuit Packet Switching 289

  Datagram Packet Switching 289

  Circuit Switching 290

  Message Switching 290

  Comparing Switching Methods 291

WAN Technologies 292

  X.25 293

  Frame Relay 293

  T-Carrier Lines 295

  T1/E1/J1 Lines 295

  T3 Lines 297

  SONET/OCx Levels 297

  Asynchronous Transfer Mode (ATM) 298

  Integrated Services Digital Network (ISDN) 299

  Basic Rate Interface (BRI) 301

  Primary Rate Interface (PRI) 301

  Comparing BRI and PRI ISDN 301

  WAN Technology Summary 301

Internet Access Technologies 302

  POTS Internet Access 303

  POTS Troubleshooting Procedures 303

  Troubleshooting Poor Connection Speeds 305

  Modem-Specific Troubleshooting 306

  xDSL 307

  Cable Internet Access 310

  Satellite Internet Access 313

Wireless Wide Area Networking 315

Summary 316

Chapter 9 OSI Model 325

OSI Reference Model 101 326

  Layer 1: The Physical Layer 328

  Layer 2: The Data Link Layer 329

  Layer 3: The Network Layer 329

  Switching Methods 330

  Network Layer Addressing 331

  Layer 4: The Transport Layer 331

  Connection-Oriented Protocols 332

  Connectionless Protocols 332

  Flow Control 333

  Layer 5: The Session Layer 333

  Layer 6: The Presentation Layer 333

  Layer 7: The Application Layer 334

  OSI Model Summary 334

The Layers at Which Devices Operate 335

  Hubs 336

  Switches 336

  Bridges 336

  Routers 336

  NICs 336

  Wireless Access Points (APs) 337

  Summary of the Layers at Which Devices Operate 337

TCP/IP Protocol Suite Summary 337

Summary 340

Chapter 10 Network Performance and Optimization 349

Understanding Uptime 350

Understanding the Risks 352

  RAID 353

  RAID 0 354

  Advantages of RAID 0 354

  Disadvantages of RAID 0 355

  Recovering from a Failed RAID 0 Array 355

  RAID 1 355

  Advantages of RAID 1 357

  Disadvantages of RAID 1 357

  Recovering from a Failed RAID 1 Array 358

  RAID 5 358

  Advantages of RAID 5 358

  Disadvantages of RAID 5 359

  Recovering from a RAID 5 Array Failure 359

  RAID 10 360

  Choosing a RAID Level 361

  Hardware and Software RAID 362

  Other Fault-Tolerance Measures 363

  Link Redundancy 363

  Using Uninterruptible Power Supplies 364

  Why Use a UPS? 365

  Power Threats 365

  Using Redundant Power Supplies 366

  Server and Services Fault Tolerance 366

  Using Standby Servers 366

  Server Clustering 367

  Preparing for Memory Failures 368

  Managing Processor Failures 368

Disaster Recovery 368

  Backup Methods 368

  Full Backups 369

  Incremental Backups 370

  Differential Backups 370

  A Comparison of Backup Methods 371

  Backup Rotation Schedules 371

  Offsite Storage 372

  Backup Best Practices 373

Hot and Cold Spares 374

  Hot Spare and Hot Swapping 374

  Cold Spare and Cold Swapping 375

  Recovery Sites 375

  Cold Site 375

  Hot Site 376

  Warm Site 376

Network Optimization Strategies 377

  QoS 377

  Latency-Sensitive High-Bandwidth Applications 378

  Voice over Internet Protocol (VoIP) 378

  Video Applications 379

  Traffic Shaping 379

  Load Balancing 381

  Caching Engines 381

Summary 382

Chapter 11 Troubleshooting Procedures and Best Practices 393

The Art of Troubleshooting 394

  Troubleshooting Servers and Workstations 394

  General Troubleshooting Considerations 395

  Troubleshooting Methods and Procedures 396

  Step 1: Information Gathering—Identify Symptoms and Problems 397

  Information from the Computer 397

  Information from the User 398

  Observation Techniques 399

  Effective Questioning Techniques 399

  Step 2: Identify the Affected Areas of the Network 399

  Step 3: Determine if Anything Has Changed 400

  Changes to the Network 400

  Changes to the Server 401

  Changes to the Workstation 402

  Step 4: Establish the Most Probable Cause 402

  Step 5: Determine if Escalation Is Necessary 403

  Step 6: Create an Action Plan and Solution Identifying Potential Effects 403

  Step 7: Implement and Test the Solution 404

  Step 8: Identify the Results and Effects of the Solution 405

  Step 9: Document the Solution and the Entire Process 406

Troubleshooting the Network 407

  Troubleshooting Wiring 407

  Where the Cable Is Used 408

  Wiring Issues 409

  Crosstalk 409

  Near-End Crosstalk (NEXT) 409

  Far-End Crosstalk (FEXT) 409

  Electromagnetic interference (EMI) 409

  Attenuation 410

  Open Impedance Mismatch (Echo) 410

  Shorts 410

  Managing Collisions 410

  Troubleshooting Infrastructure Hardware 411

  Configuring and Troubleshooting Client Connectivity 413

  Verifying Client TCP/IP Configurations 413

  Setting Port Speeds and Duplex 415

  Troubleshooting Incorrect VLANs 416

Identifying Issues That Might Need Escalation 417

Troubleshooting Wireless Issues 418

  Troubleshooting Wireless Signals 418

  Troubleshooting Wireless Configurations 420

Summary 421

Chapter 12 Command-Line Networking Tools 431

Common Networking Utilities 432

  The ping Utility 432

  Switches for ping 434

  Troubleshooting Steps with ping 435

 Ping Error Messages 436

  The Destination Host Unreachable Message 437

  The Unknown Host Message 438

  The traceroute Utility 439

  Reviewing tracert Command Printouts 441

  The traceroute Command 444

  The mtr Utility 445

  The arp Utility 445

  The ARP Cache 445

  Switches for arp 446

  The arp Command Printout 447

  The arp ping Utility 447

  The netstat Utility 448

  The netstat Command Printouts 450

  netstat -e 450

  netstat -a 451

  netstat -r 452

  netstat -s 453

  The nbtstat Utility 454

  The ipconfig and ifconfig Utilities 456

  The ipconfig Utility 457

  The ipconfig Command Printouts 458

  The ifconfig Command Printout 460

  The nslookup and dig Utilities 461

  The nslookup Utility 461

  The nslookup Command Printout 463

  The dig Utility 464

  The dig Command Printout 465

  The host Command 466

  The route Utility 466

Summary 468

Chapter 13 Network Management Tools and Documentation Procedures 479

Documentation Management 480

  Wiring Schematics 481

  Physical and Logical Network Diagrams 484

  Physical Network Documentation 484

  Logical Network Documentation 485

  Baselines 487

  Policies, Procedures, Configurations, and Regulations 488

  Policy Documentation 488

  Network Procedure Documentation 489

  Configuration Documentation 490

  Regulations 491

Monitoring the Network to Identify Performance 492

  Throughput Testing 493

  Port Scanners 495

  Network Testing 498

  Performance Testing 498

  Load Testing 498

  Stress Testing 499

  Logging 499

  Security Logs 500

  Application Logs 501

  System Logs 502

  History Logs 502

  Log Management 503

Networking Tools 503

  Wire Crimpers 504

  Strippers and Snips 504

  Punchdown Tools 505

  Cable Certifiers 505

  Voltage Event Recorders 506

  Temperature Monitors 506

  Toner Probes 508

  Protocol Analyzer 509

  Media/Cable Testers 509

  Media Testers 510

  TDR 510

  OTDR 510

  Multimeter 511

  Network Qualification Tester 512

  Butt Set 512

  Wireless Detector 512

Summary 513

Chapter 14 Network Access Security 525

Understanding Network Security Threats 526

Security Responsibilities of a Network Administrator 527

Physical and Logical Security 528

  Physical Security 528

  Network Hardware and Server Room Access 529

  Lock and Key 529

  Swipe Card and PIN Access 529

  Biometrics 530

  Hardware Room Best Practices 531

  Logical Security 532

Firewalls 532

  The Purpose and Function of a Firewall 534

  Stateful and Stateless Firewalls 536

  Firewall Methods 536

  Network Layer Firewalls 536

  Circuit-Level Firewalls 537

  Application-Layer Firewalls 537

  Demilitarized Zones 538

Intrusion Detection and Intrusion Prevention Systems 539

Network Access Security 539

  Access Control Lists 540

  Access Control and MAC Filtering 540

  TCP/IP Filtering 540

  Port Blocking/Filtering 541

Remote Access Protocols and Services 542

  Routing and Remote Access Service (RRAS) 542

  SLIP 543

  PPP 543

  PPPoE 544

Tunneling and Encryption 545

  SSL VPNs 546

  VPN Concentrators 546

  Point-to-Point Tunneling Protocol (PPTP) 547

  Layer Two Tunneling Protocol (L2TP) 548

  Advantages of L2TP and PPTP 548

Inside IPsec 548

  Authentication Headers 549

  Encapsulating Security Payloads 549

  IPsec Transmission Modes 550

Remote Control Protocols 550

Summary 551

Chapter 15 Security Technologies and Malicious Software 561

Authentication, Authorization, and Accounting (AAA) 562

  Authentication 562

  Password Policies 562

  Password Strength 563

  Multifactor Authentication 565

  Authentication Tokens 565

  Biometrics 565

  Multifactor Authentication/Two-Factor Authentication 566

  Authorization 566

  Accountability 567

RADIUS and TACACS+ 568

     RADIUS 568

  TACACS+ 570

  Understanding Cryptography Keys 570

  Kerberos Authentication 572

Public Key Infrastructure 573

  Components of a PKI 574

  Certificates 575

  Certificate Stores 576

  Trusts 576

  Certificate Authorities (CAs) 577

  Public CAs 577

  Private CAs 577

Network Access Control 578

  Mandatory Access Control (MAC) 578

  Discretionary Access Control (DAC) 579

  Rule-Based Access Control (RBAC) 579

     Role-Based Access Control (RBAC) 579

Remote Authentication Protocols 580

Using Secure Protocols 581

Malicious Software 582

  Malware Distribution 583

  Malware Payloads 584

  More About Viruses 585

  More About Trojan Horses and Worms 586

  Comparing Malware Types 586

  Types of Attacks 587

  Denial of Service and Distributed Denial of Service Attacks 587

  Other Common Attacks 589

  An Ounce of Prevention 590

Maintaining Operating System Software 592

  Reasons to Use a Service Pack 593

  When to Use a Service Pack 593

  How to Apply a Service Pack 594

  Server Patches 595

Summary 596

Appendix A Answers to the Review Questions 605

Index 639

Elements on the CD-ROM:

Appendix B Memory Tables

Appendix C Memory Tables Answer Key

Glossary