CompTIA Network+ (N10-004) Cert Guide

Mike Harwood (MCSE, A+, Network+, Server+, Linux+) has more than 14 years experience in information technology and related fields. He has held a number of roles in the IT field including network administrator, instructor, technical writer, website designer, consultant, and online marketing strategist. Mike has been a regular on-air technology contributor for CBC radio and has coauthored numerous computer books, including the Network+ Exam Cram published by Pearson.

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

TOC, 9780789745590, 7/8/10