Introduction xxx
Assessment Test lxvi
Chapter 1 Introduction to Networks 1
First Things First: What's a Network? 2
The Local Area Network 3
Common Network Components 5
Wide Area Network 7
Network Architecture: Peer-to-Peer or Client-Server? 9
Physical Network Topologies 11
Bus Topology 12
Star Topology 13
Ring Topology 14
Mesh Topology 15
Point-to-Point Topology 16
Point-to-Multipoint Topology 17
Hybrid Topology 18
Topology Selection, Backbones, and Segments 19
Selecting the Right Topology 19
The Network Backbone 20
Network Segments 21
CAN 21
SAN 21
Summary 21
Exam Essentials 22
Written Lab 22
Review Questions 23
Chapter 2 The Open Systems Interconnection Specifications 27
Internetworking Models 28
The Layered Approach 29
Advantages of Reference Models 29
The OSI Reference Model 30
The Application Layer 32
The Presentation Layer 33
The Session Layer 33
The Transport Layer 33
The Network Layer 40
The Data Link Layer 42
The Physical Layer 45
Introduction to Encapsulation 45
Modulation Techniques 46
Summary 47
Exam Essentials 48
Written Lab 48
Review Questions 50
Chapter 3 Networking Topologies, Connectors, and Wiring Standards 55
Physical Media 57
Coaxial Cable 58
Twisted-Pair Cable 60
Fiber-Optic Cable 64
Transceivers 69
Media Converters 69
Serial Cables 71
Cable Properties 73
Transmission Speeds 73
Distance 74
Duplex 74
Noise Immunity (Security, EMI) 74
Frequency 75
Wiring Standards 75
T568A vs. T568B 75
Straight-Through Cable 77
Crossover Cable 78
Rolled/Rollover Cable 80
T1 Crossover Cable 80
Installing Wiring Distributions 82
MDF/IDF 82
Summary 84
Exam Essentials 85
Written Lab 85
Review Questions 87
Chapter 4 The Current Ethernet Specifications 91
Network Basics 92
Ethernet Basics 94
Collision Domain 94
Broadcast Domain 94
CSMA/CD 95
Broadband/Baseband 96
Bit Rates vs. Baud Rate 97
Wavelength 97
Half- and Full-Duplex Ethernet 98
Ethernet at the Data Link Layer 99
Binary to Decimal and Hexadecimal Conversion 100
Ethernet Addressing 103
Ethernet Frames 104
Ethernet at the Physical Layer 106
Ethernet over Other Standards (IEEE 1905.1-2013) 111
Ethernet over Power Line 112
Ethernet over HDMI 113
Summary 114
Exam Essentials 115
Written Lab 115
Review Questions 120
Chapter 5 Networking Devices 125
Common Network Connectivity Devices 128
Network Interface Card 129
Hub 130
Bridge 131
Switch 131
Router 132
Firewall 136
IDS/IPS 137
HIDS 137
Access Point 138
Wireless Range Extender 138
Contention Methods 139
Dynamic Host Configuration Protocol Server 141
IPAM 146
Other Specialized Devices 146
Multilayer Switch 147
Load Balancer 147
Domain Name Service Server 148
Proxy Server 154
Encryption Devices 155
Analog Modem 156
Packet Shaper 157
VPN Concentrator 157
Media Converter 158
VoIP PBX 158
VoIP Endpoint 158
NGFW/Layer 7 Firewall 159
VoIP Gateway 159
Planning and Implementing a Basic SOHO Network Using Network Segmentation 159
Determining Requirements 159
Switches and Bridges at the Data Link Layer 166
Hubs at the Physical Layer 167
Environmental Considerations 168
Summary 169
Exam Essentials 169
Written Lab 170
Review Questions 171
Chapter 6 Introduction to the Internet Protocol 175
Introducing TCP/IP 177
A Brief History of TCP/IP 177
TCP/IP and the DoD Model 178
The Process/Application Layer Protocols 180
The Host-to-Host Layer Protocols 188
The Internet Layer Protocols 192
Data Encapsulation 198
Summary 202
Exam Essentials 202
Written Lab 203
Review Questions 204
Chapter 7 IP Addressing 209
IP Terminology 210
The Hierarchical IP Addressing Scheme 211
Network Addressing 212
Private IP Addresses (RFC 1918) 216
IPv4 Address Types 218
Layer 2 Broadcasts 219
Layer 3 Broadcasts 219
Unicast Address 219
Multicast Address (Class D) 219
Internet Protocol Version 6 (IPv6) 220
Why Do We Need IPv6? 220
The Benefits of and Uses for IPv6 221
IPv6 Addressing and Expressions 222
Shortened Expression 223
Address Types 224
Special Addresses 225
Stateless Autoconfiguration (EUI-64) 226
DHCPv6 (Stateful) 227
Migrating to IPv6 227
Summary 230
Exam Essentials 230
Written Labs 231
Written Lab 7.1 231
Written Lab 7.2 232
Written Lab 7.3 232
Review Questions 233
Chapter 8 IP Subnetting, Troubleshooting IP, and Introduction to NAT 237
Subnetting Basics 238
How to Create Subnets 239
Subnet Masks 240
Classless Inter-Domain Routing (CIDR) 241
Subnetting Class C Addresses 243
Subnetting Class B Addresses 253
Troubleshooting IP Addressing 260
Determining IP Address Problems 263
Introduction to Network Address Translation (NAT) 268
Types of Network Address Translation 269
NAT Names 269
How NAT Works 270
Summary 272
Exam Essentials 272
Written Lab 273
Review Questions 274
Chapter 9 Introduction to IP Routing 279
Routing Basics 280
The IP Routing Process 283
Testing Your IP Routing Understanding 289
Static and Dynamic Routing 291
Summary 294
Exam Essentials 294
Written Lab 294
Review Questions 296
Chapter 10 Routing Protocols 301
Routing Protocol Basics 302
Administrative Distances 303
Classes of Routing Protocols 305
Distance Vector Routing Protocols 306
Routing Information Protocol (RIP) 308
RIP Version 2 (RIPv2) 308
VLSM and Discontiguous Networks 309
EIGRP 312
Border Gateway Protocol (BGP) 314
Link State Routing Protocols 315
Open Shortest Path First (OSPF) 316
Intermediate System-to-Intermediate System (IS-IS) 318
High Availability 319
Hot Standby Router Protocol (HSRP) 321
Virtual Router Redundancy Protocol 325
Advanced IPv6 Concepts 326
Router Advertisement 326
Neighbor Discovery 328
Tunneling 329
Dual Stack 332
IPv6 Routing Protocols 332
RIPng 333
EIGRPv6 333
OSPFv3 333
Summary 334
Exam Essentials 334
Written Lab 335
Review Questions 336
Chapter 11 Switching and Virtual LANs 341
Networking Before Layer 2 Switching 343
Switching Services 346
Limitations of Layer 2 Switching 347
Bridging vs. LAN Switching 348
Three Switch Functions at Layer 2 348
Distributed Switching 354
Spanning Tree Protocol 354
Spanning Tree Port States 355
STP Convergence 356
Rapid Spanning Tree Protocol 802.1w 357
Virtual LANs 358
VLAN Basics 359
Quality of Service 362
VLAN Memberships 363
Static VLANs 363
Dynamic VLANs 364
Identifying VLANs 364
VLAN Identification Methods 366
VLAN Trunking Protocol 367
VTP Modes of Operation 368
Do We Really Need to Put an IP Address on a Switch? 369
Switch Port Protection 372
Port Bonding 375
Device Hardening 376
Two Additional Advanced Features of Switches 376
Power over Ethernet (802.3af, 802.3at) 376
Port Mirroring/Spanning (SPAN/RSPAN) 379
Summary 380
Exam Essentials 381
Written Lab 381
Review Questions 383
Chapter 12 Wireless Networking 387
Introduction to Wireless Technology 390
Cellular 393
The 802.11 Standards 393
2.4 GHz (802.11b) 395
2.4 GHz (802.11g) 396
5 GHz (802.11a) 397
5 GHz (802.11h) 397
2.4 GHz/5 GHz (802.11n) 398
5 GHz (802.11ac) 399
Comparing 802.11 Standards 399
Range Comparisons 400
Wireless Network Components 401
Wireless Access Points 401
Wireless Network Interface Card 402
Wireless Antennas 403
Installing a Wireless Network 405
Ad Hoc Mode: Independent Basic Service Set 405
Infrastructure Mode: Basic Service Set 406
Wireless Controllers 407
Mobile Hot Spots 409
Signal Degradation 410
Other Network Infrastructure Implementations 410
Technologies that facilitate the Internet of Things (IoT) 412
Installing and Configuring WLAN Hardware 412
Site Survey 418
Providing Capacity 418
Multiple Floors 420
Location-Based WLAN 421
Site Survey Tools 421
Wireless Security 422
Wireless Threats 422
Open Access 426
Service Set Identifiers, Wired Equivalent Privacy, and Media Access Control Address Authentication 426
Remote Authentication Dial-In User Service (802.1X) 427
Temporal Key Integrity Protocol 428
Wi-Fi Protected Access or WPA2 Pre-Shared Key 430
Summary 433
Exam Essentials 433
Written Lab 434
Review Questions 435
Chapter 13 Authentication and Access Control 439
Security Filtering 441
Access Control Lists 442
Tunneling 443
Encryption 451
Remote Access 455
Managing User Account and Password Security 458
Managing User Accounts 459
Managing Passwords 461
Single Sign-On 465
Local Authentication 466
LDAP 466
Certificates 466
Multifactor Authentication 467
User-Authentication Methods 468
Public Key Infrastructure (PKI) 468
Kerberos 469
Authentication, Authorization, and Accounting (AAA) 470
Web Services 472
Unified Voice Services 472
Network Controllers 472
Network Access Control (NAC) 472
Challenge Handshake Authentication Protocol (CHAP) 473
MS-CHAP 474
Extensible Authentication Protocol (EAP) 474
Hashes 474
Network Access Control 475
Summary 476
Exam Essentials 477
Written Lab 477
Review Questions 479
Chapter 14 Network Threats and Mitigation 483
Recognizing Security Threats 485
Denial of Service 486
Distributed DoS (DDoS) 487
Authentication Issues 495
Viruses 496
Zero-Day Attacks 499
Insider Threat/Malicious Employee 500
Vulnerabilities 500
Exploits vs. Vulnerabilities 500
Unnecessary Running Services 500
Open Ports 500
Unpatched/Legacy Systems 501
Unencrypted Channels 501
TEMPEST/RF Emanation 501
Malicious Users 501
Buffer Overflow 503
DNS Poisoning 503
Wireless Threats 503
Attackers and Their Tools 506
Misconfiguration Issues 510
Social Engineering (Phishing) 511
Understanding Mitigation Techniques 512
Active Detection 513
Passive Detection 513
Proactive Defense 513
Basic Forensic Concepts 514
Policies and Procedures 516
Security Policies 517
Security Training 524
Patches and Upgrades 525
Firmware Updates 527
Driver Updates 527
File Hashing 528
Generating New Keys 528
Upgrading vs. Downgrading 528
Asset Disposal 530
Detection 531
Anti-malware Software 532
Host Based 533
Cloud/Server Based 533
Configuration Backups 534
Updating Antivirus Components 534
Fixing an Infected Computer 536
Summary 537
Exam Essentials 537
Written Lab 537
Review Questions 539
Chapter 15 Physical Security and Risk 543
Using Hardware and Software Security Devices 545
Defining Firewalls 547
Network-Based Firewalls 548
Host-Based Firewalls 548
Firewall Technologies 548
Access Control Lists 549
Port Security 551
Demilitarized Zone 552
Protocol Switching 553
Dynamic Packet Filtering 555
Proxy Services 556
Firewalls at the Application Layer vs. the Network Layer 558
Stateful vs. Stateless Network Layer Firewalls 559
NGFW/Layer7 Firewall 560
Scanning Services and Other Firewall Features 561
Content Filtering 562
Signature Identification 563
Context Awareness 563
Virtual Wire vs. Routed 563
Zones 564
Intrusion Detection and Prevention Systems 566
Network-Based IDS 567
Host-Based IDS 569
Vulnerability Scanners 570
VPN Concentrators 571
Understanding Problems Affecting Device Security 572
Physical Security 572
Logical Security Configurations 577
Risk-Related Concepts 579
Summary 586
Exam Essentials 587
Written Lab 588
Review Questions 589
Chapter 16 Wide Area Networks 593
What's a WAN? 596
Defining WAN Terms 596
The Public Switched Telephone Network 598
WAN Connection Types 599
Bandwidth or Speed 600
T-Series Connections 601
The T1 Connection 602
The T3 Connection 603
Transmission Media 603
Wired Connections 603
Wavelength Division Multiplexing 604
Passive Optical Network 605
Wireless Technologies 605
Broadband Services 607
DSL Technology and xDSL 608
Cable Modem 610
Wireless WAN Technologies 611
Cellular WAN 612
WAN Protocols 613
Integrated Services Digital Network 613
Frame Relay Technology 615
Point-to-Point Protocol 618
DMVPN 621
SIP Trunks 621
Asynchronous Transfer Mode 622
MPLS 623
WAN Troubleshooting 623
Loss of Internet Connectivity 624
Interface Errors/Monitoring 624
Split Horizon 627
DNS Issues 628
Router Configurations 628
Company Security Policy 629
Summary 629
Exam Essentials 630
Written Lab 631
Review Questions 632
Chapter 17 Troubleshooting Tools 635
Protocol Analyzers 637
Throughput Testers 638
Connectivity Software 639
Using traceroute 640
Using ipconfig and ifconfig 642
Using the ifconfig Utility 646
Using the iptables utility 646
Using the ping Utility 647
Using the Address Resolution Protocol 650
The Windows ARP Table 651
Using the arp Utility 651
Using the nslookup Utility 654
Resolving Names with the Hosts Table 656
Using the Mtr Command (pathping) 657
Using the Nmap Utility 658
Using the route Command 659
Using the route Command Options 661
Some Examples of the route Command 662
Using the nbtstat Utility 663
The -a Switch 663
The -A Switch 665
The -c Switch 665
The -n Switch 666
The -r Switch 666
The -R Switch 667
The -S Switch 668
The -s Switch 668
Using the netstat Utility 669
The -a Switch 671
The -e Switch 672
The -r Switch 673
The -s Switch 673
The -p Switch 673
The -n Switch 675
Using tcpdump 676
Examples of Using tcpdump 676
Using the File Transfer Protocol 677
Starting FTP and Logging In to an FTP Server 678
Downloading Files 679
Uploading Files 681
Using the Telnet Utility 682
How to Enable Telnet in Windows 682
Don't Use Telnet, Use Secure Shell 683
Summary 684
Exam Essentials 684
Written Lab 685
Review Questions 686
Chapter 18 Software and Hardware Tools 691
Understanding Network Scanners 693
Packet Sniffers/Network Monitors 693
Intrusion Detection and Prevention Software 695
Port Scanners 697
Wi-Fi Analyzer 700
Bandwidth Speed Tester 701
Baseline 702
Network Monitoring and Logging 703
Network Monitoring 703
SNMP 704
Syslog 705
SIEM 707
Utilization 710
Identifying Hardware Tools 712
Cable Testers 712
Protocol Analyzer 715
Certifiers 716
Time-Domain Reflectometer 717
Optical Time-Domain Reflectometer 717
Multimeter 718
Spectrum Analyzer 719
Toner Generator (Probe) 720
Metrics 721
Butt Set 721
Punch-Down Tool 722
Cable Stripper/Snips 723
Voltage Event Recorder (Power) 723
Environmental Monitors 724
Summary 725
Exam Essentials 725
Written Lab 726
Review Questions 727
Chapter 19 Network Troubleshooting 731
Narrowing Down the Problem 734
Did You Check the Super Simple Stuff? 735
Is Hardware or Software Causing the Problem? 738
Is It a Workstation or a Server Problem? 739
Which Segments of the Network Are Affected? 740
Is It Bad Cabling? 740
Troubleshooting Steps 749
Step 1: Identify the Problem 750
Step 2: Establish a Theory of Probable Cause 754
Step 3: Test the Theory to Determine Cause 762
Step 4: Establish a Plan of Action to Resolve the Problem and Identify Potential Effects 764
Step 5: Implement the Solution or Escalate as Necessary 766
Step 6: Verify Full System Functionality, and If Applicable, Implement Preventative Measures 769
Step 7: Document Findings, Actions, and Outcomes 769
Troubleshooting Tips 770
Don't Overlook the Small Stuff 770
Prioritize Your Problems 771
Check the Software Configuration 771
Don't Overlook Physical Conditions 772
Don't Overlook Cable Problems 772
Check for Viruses 773
Summary 773
Exam Essentials 774
Written Lab 774
Review Questions 776
Chapter 20 Management, Monitoring, and Optimization 781
Managing Network Documentation 785
Using SNMP 785
Schematics and Diagrams 786
Network Monitoring 795
Baselines 795
Processes 796
On-Boarding and Off-Boarding of Mobile Devices 796
NAC 796
Policies, Procedures, and Regulations 797
Safety Practices 801
Implementing Network Segmentation 805
Network Optimization 808
Reasons to Optimize Your Network's Performance 808
How to Optimize Performance 811
Unified Communications 813
Traffic Shaping 813
Load Balancing 814
High Availability 814
Caching Engines 815
Fault Tolerance 815
Archives/Backups 815
Common Address Redundancy Protocol 816
Virtual Networking 817
Locating and Installing Equipment 825
Change Management Procedures 832
Summary 834
Exam Essentials 835
Written Lab 836
Review Questions 837
Appendix A Answers to Written Labs 841
Chapter 1: Introduction to Networks 842
Chapter 2: The Open Systems Interconnection Specifications 842
Chapter 3: Networking Topologies, Connectors, and Wiring Standards 843
Chapter 4: The Current Ethernet Specifications 843
Chapter 5: Networking Devices 845
Chapter 6: Introduction to the Internet Protocol 846
Chapter 7: IP Addressing 847
Written Lab 7.1 847
Written Lab 7.2 847
Written Lab 7.3 848
Chapter 8: IP Subnetting, Troubleshooting IP, and Introduction to NAT 848
Chapter 9: Introduction to IP Routing 849
Chapter 10: Routing Protocols 849
Chapter 11: Switching and Virtual LANs 850
Chapter 12: Wireless Networking 850
Chapter 13: Authentication and Access Control 850
Chapter 14: Network Threats and Mitigation 851
Chapter 15: Physical Security and Risk 851
Chapter 16: Wide Area Networks 852
Chapter 17: Troubleshooting Tools 852
Chapter 18: Software and Hardware Tools 853
Chapter 19: Network Troubleshooting 853
Chapter 20: Management, Monitoring, and Optimization 854
Appendix B Answers to Review Questions 855
Chapter 1: Introduction to Networks 856
Chapter 2: The Open Systems Interconnection Specifications 857
Chapter 3: Networking Topologies, Connectors, and Wiring Standards 859
Chapter 4: The Current Ethernet Specifications 860
Chapter 5: Networking Devices 861
Chapter 6: Introduction to the Internet Protocol 863
Chapter 7: IP Addressing 864
Chapter 8: IP Subnetting, Troubleshooting IP, and Introduction to NAT 866
Chapter 9: Introduction to IP Routing 868
Chapter 10: Routing Protocols 869
Chapter 11: Switching and Virtual LANs 871
Chapter 12: Wireless Networking 872
Chapter 13: Authentication and Access Control 874
Chapter 14: Network Threats and Mitigation 875
Chapter 15: Physical Security and Risk 877
Chapter 16: Wide Area Networks 878
Chapter 17: Troubleshooting Tools 880
Chapter 18: Software and Hardware Tools 881
Chapter 19: Network Troubleshooting 883
Chapter 20: Management, Monitoring, and Optimization 885
Appendix C Subnetting Class A 887
Subnetting Practice Examples: Class A Addresses 888
Practice Example #1A: 255.255.0.0 (/16) 888
Practice Example #2A: 255.255.240.0 (/20) 889
Practice Example #3A: 255.255.255.192 (/26) 889
Subnetting in Your Head: Class A Addresses 890
Written Lab 1 891
Written Lab 2 892
Answers to Written Lab 1 892
Answers to Written Lab 2 893
Index 895
