Introduction xxxi
Getting Started 1
Part I: Networking Fundamentals 9
Chapter 1 The TCP/IP and OSI Networking Models 11
Do I Know This Already? Quiz 11
Foundation Topics 14
Perspectives on Networking 14
TCP/IP Networking Model 15
History Leading to TCP/IP 16
Overview of the TCP/IP Networking Model 17
TCP/IP Application Layer 19
HTTP Overview 19
HTTP Protocol Mechanisms 20
TCP/IP Transport Layer 21
TCP Error Recovery Basics 21
Same-Layer and Adjacent-Layer Interactions 22
TCP/IP Network Layer 22
Internet Protocol and the Postal Service 23
Internet Protocol Addressing Basics 24
IP Routing Basics 25
TCP/IP Link Layer (Data Link Plus Physical) 26
TCP/IP Model and Terminology 28
Comparing the Original and Modern TCP/IP Models 28
Data Encapsulation Terminology 28
Names of TCP/IP Messages 30
OSI Networking Model 30
Comparing OSI and TCP/IP 30
Describing Protocols by Referencing the OSI Layers 31
OSI Layers and Their Functions 32
OSI Layering Concepts and Benefits 33
OSI Encapsulation Terminology 34
Exam Preparation Tasks 36
Review All the Key Topics 36
Definitions of Key Terms 36
Chapter 2 Fundamentals of Ethernet LANs 39
Do I Know This Already? Quiz 39
Foundation Topics 42
An Overview of LANs 42
Typical SOHO LANs 42
Typical Enterprise Campus LANs 43
Typical Data Center Ethernet LAN 44
The Variety of Ethernet Physical Layer Standards 45
Consistent Behavior over All Links Using the Ethernet Data Link Layer 46
Building Physical Ethernet Networks with UTP 47
Transmitting Data Using Twisted Pairs 47
Breaking Down a UTP Ethernet Link 48
UTP Cabling Pinouts for 10BASE-T and 100BASE-T 51
Straight-Through Cable Pinout 51
Crossover Cable Pinout 53
Choosing the Right Cable Pinouts 54
UTP Cabling Pinouts for 1000BASE-T 55
Sending Data in Ethernet Networks 55
Ethernet Data-Link Protocols 55
Ethernet Addressing 56
Identifying Network Layer Protocols with the Ethernet Type Field 58
Error Detection with FCS 59
Sending Ethernet Frames with Switches and Hubs 59
Sending in Modern Ethernet LANs Using Full-Duplex 59
Using Half-Duplex with LAN Hubs 60
Exam Preparation Tasks 63
Review All the Key Topics 63
Complete the Tables and Lists from Memory 63
Definitions of Key Terms 64
Chapter 3 Fundamentals of WANs 67
Do I Know This Already? Quiz 67
Foundation Topics 70
Leased Line WANs 70
Positioning Leased Lines with LANs and Routers 70
Physical Details of Leased Lines 71
Leased Line Cabling 72
Building a WAN Link in a Lab 73
Data Link Details of Leased Lines 74
HDLC Basics 74
How Routers Use a WAN Data Link 75
Ethernet as a WAN Technology 77
Ethernet WANs that Create a Layer 2 Service 78
How Routers Route IP Packets Using Ethernet Emulation 79
Accessing the Internet 80
The Internet as a Large WAN 80
Internet Access (WAN) Links 81
Digital Subscriber Line 82
Cable Internet 84
Exam Preparation Tasks 86
Review All the Key Topics 86
Complete the Tables and Lists from Memory 86
Definitions of Key Terms 86
Chapter 4 Fundamentals of IPv4 Addressing and Routing 89
Do I Know This Already? Quiz 89
Foundation Topics 92
Overview of Network Layer Functions 92
Network Layer Routing (Forwarding) Logic 92
Host Forwarding Logic: Send the Packet to the Default Router 93
R1 and R2's Logic: Routing Data Across the Network 94
R3's Logic: Delivering Data to the End Destination 94
How Network Layer Routing Uses LANs and WANs 94
IP Addressing and How Addressing Helps IP Routing 95
Routing Protocols 97
IPv4 Addressing 97
Rules for IP Addresses 98
Rules for Grouping IP Addresses 98
Class A, B, and C IP Networks 99
The Actual Class A, B, and C IP Networks 101
IP Subnetting 103
IPv4 Routing 105
IPv4 Host Routing 105
Router Forwarding Decisions and the IP Routing Table 106
A Summary of Router Forwarding Logic 106
A Detailed Routing Example 107
IPv4 Routing Protocols 109
Other Network Layer Features 111
Using Names and the Domain Name System 111
The Address Resolution Protocol 112
ICMP Echo and the ping Command 113
Exam Preparation Tasks 115
Review All the Key Topics 115
Complete the Tables and Lists from Memory 115
Definitions of Key Terms 115
Chapter 5 Fundamentals of TCP/IP Transport and Applications 117
Do I Know This Already? Quiz 117
Foundation Topics 120
TCP/IP Layer 4 Protocols: TCP and UDP 120
Transmission Control Protocol 121
Multiplexing Using TCP Port Numbers 122
Popular TCP/IP Applications 125
Connection Establishment and Termination 126
Error Recovery and Reliability 127
Flow Control Using Windowing 130
User Datagram Protocol 131
TCP/IP Applications 132
QoS Needs and the Impact of TCP/IP Applications 132
Defining Interactive and Batch Applications 132
Real-Time Voice and Video Applications 133
The World Wide Web, HTTP, and SSL 134
Uniform Resource Locators 134
Finding the Web Server Using DNS 135
Transferring Files with HTTP 137
How the Receiving Host Identifies the Correct Receiving Application 138
Exam Preparation Tasks 140
Review All the Key Topics 140
Complete the Tables and Lists from Memory 140
Definitions of Key Terms 140
Part I Review 142
Part II: Ethernet LAN Basics 147
Chapter 6 Building Ethernet LANs with Switches 149
Do I Know This Already? Quiz 149
Foundation Topics 152
Ethernet History 152
Early Ethernet with Coaxial Cabling 152
Ethernet Devices 154
Ethernet Repeaters 154
10BASE-T with Hub 155
Ethernet Transparent Bridges 157
Ethernet Switches 158
Ethernet Standards 159
Ethernet Data-Link Protocols 160
Ethernet Physical Layer Standards 161
Ethernet Competition 162
Switching Logic 164
Layer 2 Switching Basics 164
The Forward Versus Filter Decision 165
How Switches Learn MAC Addresses 167
Flooding Frames 167
Avoiding Loops Using Spanning Tree Protocol 168
LAN Switching Summary 169
Design Choices in Ethernet LANs 170
Collision Domains, Broadcast Domains, and VLANs 170
Collision Domains 170
Broadcast Domains 171
Virtual LANs and Broadcast Domains 172
The Impact of Collision and Broadcast Domains on LAN Design 173
Ethernet LAN Media and Cable Lengths 174
Autonegotiation 175
Autonegotiation Results When Only One Node Uses Autonegotiation 176
Autonegotiation and LAN Hubs 178
Exam Preparation Tasks 179
Review All the Key Topics 179
Complete the Tables and Lists from Memory 179
Definitions of Key Terms 180
Chapter 7 Installing and Operating Nexus Switches 183
Do I Know This Already? Quiz 183
Foundation Topics 186
Accessing the Cisco Nexus 5500 Switch CLI 186
Cisco Nexus Switches and the 5500 Switch 186
Accessing the Cisco NX-OS CLI 186
Cabling the Console Connection 187
Configuring the Terminal Emulator for the Console 188
Accessing the CLI with Telnet and SSH in NX-OS 189
Management Interface 190
Password Security for CLI Access 191
User Settings 192
CLI Help Features 194
The debug and show Commands 196
Introduction to Cisco NX-OS 196
Software Modularity in Cisco NX-OS 197
Service Restart in Cisco NX-OS 198
Software High Availability in Cisco NX-OS 199
In-Service Software Upgrades 199
Cisco NX-OS Licensing 200
Cisco NX-OS and Cisco IOS Comparison 201
Configuring Cisco NX-OS Software 202
Configuration Submodes and Contexts 202
Storing Switch Configuration Files 204
Copying and Erasing Configuration Files 206
Initial Configuration (Setup Mode) 208
NX-OS Version and Other Reload Facts 209
Exam Preparation Tasks 211
Review All the Key Topics 211
Complete the Tables and Lists from Memory 211
Definitions of Key Terms 211
Command References 211
Chapter 8 Configuring Ethernet Switching 215
Do I Know This Already? Quiz 215
Foundation Topics 217
Configuration of Features in Common on all Nexus Switches 217
Securing the Switch CLI 217
Securing Access with Local Usernames and Passwords 217
Securing Access with External Authentication Servers 218
Configuring Secure Shell 219
Banners 220
History Buffer Commands 221
The logging synchronous and exec-timeout Commands 222
Nexus Switch Configuration and Operation 222
Switch Virtual Interface Concept Inside a Switch 223
Configuring IPv4 on a Cisco Nexus Switch 223
Verifying IPv4 on a Switch 224
Configuring Switch Interfaces 225
Securing Unused Switch Interfaces 226
Predicting the Contents of the MAC Address Table 227
Scenario 1: Communication Between S1 and S2 228
Scenario 2: Communication from S1 to S3 228
Exam Preparation Tasks 230
Review All the Key Topics 230
Complete the Tables and Lists from Memory 230
Definitions of Key Terms 230
Command References 230
Part II Review 234
Part III: Ethernet Virtual LANs and Spanning Tree 239
Chapter 9 VLAN and Trunking Concepts 241
Do I Know This Already? Quiz 241
Foundation Topics 244
Virtual LANs and VLAN Trunks 244
Creating Multiswitch VLANs Using Trunking 245
The 802.1Q and ISL VLAN Trunking Protocols 247
Forwarding Data Between VLANs 248
Routing Packets Between VLANs with a Router 249
Routing Packets with a Layer 3 Switch 251
VLAN Trunking Protocol 252
VTP Functions 252
Making VTP Work with VTP Servers and Clients 253
Disabling VTP 256
Summary of VTP Features 257
Exam Preparation Tasks 259
Review All the Key Topics 259
Complete the Tables and Lists from Memory 259
Definitions of Key Terms 259
Chapter 10 VLAN Trunking and Configuration 261
Do I Know This Already? Quiz 261
Foundation Topics 264
VLAN Configuration and Verification 264
VLAN Guidelines for Cisco Nexus Switches 264
Creating VLANs and Assigning Access VLANs to an Interface 265
VLAN Configuration Example 1: Full VLAN Configuration 265
VLAN Configuration Example 2: Shorter VLAN Configuration 268
VLAN Trunking Configuration and Verification 268
Controlling Which VLANs Can Be Supported on a Trunk 271
VTP Configuration and Verification 275
Enabling VTP 275
Limiting VTP Using Pruning 278
Exam Preparation Tasks 280
Review All the Key Topics 280
Complete the Tables and Lists from Memory 280
Command Reference to Check Your Memory 280
Chapter 11 Spanning Tree Protocol Concepts 283
Do I Know This Already? Quiz 283
Foundation Topics 286
Spanning Tree Protocol (IEEE 802.1D) 286
The Need for Spanning Tree 286
What IEEE 802.1D Spanning Tree Does 288
How Spanning Tree Works 290
The STP Bridge ID and Hello BPDU 291
Electing the Root Switch 292
Choosing Each Switch's Root Port 294
Tiebreakers for Root Port 296
Choosing the Designated Port on Each LAN Segment 296
Influencing and Changing the STP Topology 297
Making Configuration Changes to Influence the STP Topology 298
Reacting to State Changes That Affect the STP Topology 298
How Switches React to Changes with STP 299
Changing Interface States with STP 300
Optional STP Features 301
EtherChannel 302
PortFast 303
BPDU Guard 303
Rapid STP (IEEE 802.1w) 304
RSTP and the Alternate (Root) Port 305
RSTP States and Processes 306
RSTP Backup (Designated) Ports 307
Exam Preparation Tasks 309
Review All the Key Topics 309
Complete the Tables and Lists from Memory 309
Definitions of Key Terms 309
Chapter 12 Cisco Nexus Spanning Tree Protocol Implementation 311
Do I Know This Already? Quiz 311
Foundation Topics 314
STP Configuration and Verification 314
Connecting STP Concepts to STP Configuration Options 315
Per-VLAN Configuration Settings 315
The Bridge ID and System ID Extension 316
Per-VLAN Port Costs 317
STP Configuration Option Summary 317
Verifying STP Operation 318
Improving STP Operation 321
Configuring STP Port Costs 321
Configuring Priority to Influence the Root Election 322
Spanning-Tree Port Types 324
Configuring PortFast and BPDU Guard 324
Configuring EtherChannel 326
Configuring a Manual EtherChannel 326
Configuring Dynamic EtherChannels 328
Troubleshooting EtherChannel 329
Incorrect Options on the channel-group Command 329
Configuration Checks Before Adding Interfaces to EtherChannels 331
Exam Preparation Tasks 333
Review All the Key Topics 333
Definitions of Key Terms 333
Command Reference to Check Your Memory 333
Part III Review 336
Part IV: IP Addressing and Subnetting 341
Chapter 13 Perspectives on IPv4 Subnetting 343
Do I Know This Already? Quiz 343
Foundation Topics 346
Introduction to Subnetting 346
Subnetting Defined Through a Simple Example 346
Operational View Versus Design View of Subnetting 347
Analyze Subnetting and Addressing Needs 348
Rules About Which Hosts Are in Which Subnet 348
Subnet Rules with Layer 3 Switches 349
Determine the Number of Subnets 351
Determine the Number of Hosts per Subnet 353
One Size Subnet Fits All (Or Not) 354
Defining the Size of a Subnet 354
One Size Subnet Fits All 355
Multiple Subnet Sizes (Variable-Length Subnet Masks) 356
Make Design Choices 357
Choose a Classful Network 357
Public IP Networks 357
Growth Exhausts the Public IP Address Space 358
Private IP Networks 359
Choose an IP Network During the Design Phase 360
Choose the Mask 360
Classful IP Networks Before Subnetting 361
Borrow Host Bits to Create Subnet Bits 361
Choose Enough Subnet and Host Bits 362
Example Design: 172.16.0.0, 200 Subnets, 200 Hosts 364
Masks and Mask Formats 364
Build a List of All Subnets 365
Plan the Implementation 366
Assign Subnets to Different Locations 367
Choose Static and Dynamic Ranges per Subnet 367
Foundation Topics 369
Review All the Key Topics 369
Complete the Tables and Lists from Memory 369
Definitions of Key Terms 369
Chapter 14 Analyzing Classful IPv4 Networks 371
Do I Know This Already? Quiz 371
Foundation Topics 374
Classful Network Concepts 374
IPv4 Network Classes and Related Facts 374
Actual Class A, B, and C Networks 375
Address Formats 376
Default Masks 377
Number of Hosts per Network 377
Deriving the Network ID and Related Numbers 378
Unusual Network IDs and Network Broadcast Addresses 380
Practice with Classful Networks 381
Practice Deriving Key Facts Based on an IP Address 381
Practice Remembering the Details of Address Classes 382
Additional Practice 383
Exam Preparation Tasks 384
Review All the Key Topics 384
Complete the Tables and Lists from Memory 384
Definitions of Key Terms 384
Practice 384
Answers to Earlier Practice Problems 385
Answers to Practice Problem 7 (From Table 14-5) 385
Answers to Practice Problem 8 (From Table 14-5) 386
Answers to Practice Problem 9 (From Table 14-5) 386
Chapter 15 Analyzing Subnet Masks 389
Do I Know This Already? Quiz 389
Foundation Topics 392
Subnet Mask Conversion 392
Three Mask Formats 392
Converting Between Binary and Prefix Masks 393
Converting Between Binary and DDN Masks 394
Converting Between Prefix and DDN Masks 396
Practice Converting Subnet Masks 397
Identifying Subnet Design Choices Using Masks 398
Masks Divide the Subnet's Addresses into Two Parts 399
Masks and Class Divide Addresses into Three Parts 400
Classless and Classful Addressing 401
Calculations Based on the IPv4 Address Format 401
Practice Analyzing Subnet Masks 403
Exam Preparation Tasks 405
Review All the Key Topics 405
Complete the Tables and Lists from Memory 405
Definitions of Key Terms 405
Practice 405
Answers to Earlier Practice Problems 406
Chapter 16 Analyzing Existing Subnets 409
Do I Know This Already? Quiz 409
Foundation Topics 412
Defining a Subnet 412
An Example with Network 172.16.0.0 and Four Subnets 412
Subnet ID Concepts 414
Subnet Broadcast Address 415
Range of Usable Addresses 415
Analyzing Existing Subnets: Binary 416
Finding the Subnet ID: Binary 416
Finding the Subnet Broadcast Address: Binary 418
Binary Practice Problems 419
Shortcut for the Binary Process 420
Brief Note About Boolean Math 422
Finding the Range of Addresses 422
Analyzing Existing Subnets: Decimal 422
Analysis with Easy Masks 423
Predictability in the Interesting Octet 424
Finding the Subnet ID: Difficult Masks 425
Resident Subnet Example 1 426
Resident Subnet Example 2 427
Resident Subnet Practice Problems 427
Finding the Subnet Broadcast Address: Difficult Masks 428
Subnet Broadcast Example 1 428
Subnet Broadcast Example 2 429
Subnet Broadcast Address Practice Problems 430
Practice Analyzing Existing Subnets 430
A Choice: Memorize or Calculate 430
Additional Practice 431
Exam Preparation Tasks 432
Review All the Key Topics 432
Complete the Tables and Lists from Memory 432
Definitions of Key Terms 432
Practice 432
Answers to Earlier Practice Problems 433
Chapter 17 Fundamentals of IP Version 6 437
Do I Know This Already? Quiz 437
Foundation Topics 440
Introduction to IP Version 6 440
The Need and Effect of a New Internet Protocol 440
Additional Motivations for IPv6 441
Many Protocols Updated 442
Introduction to IPv6 Addresses and Prefixes 442
Representing Full (Unabbreviated) IPv6 Addresses 443
Abbreviating IPv6 Addresses 443
Expanding IPv6 Addresses 444
Representing the Prefix Length of an Address 445
Calculating the IPv6 Prefix (Subnet ID) 445
Assigning Unique IPv6 Prefixes Across the Globe 447
IPv6 Addressing and Subnetting 449
Global Unicast Addresses and IPv6 Subnetting 449
IPv6 Subnetting Concepts 450
Assign Subnets and Addresses 452
The Actual Global Unicast Addresses 453
Unique Local Unicast Addresses 453
Link Local Addresses 454
IPv6 Multicast Addresses 455
Miscellaneous IPv6 Addresses 456
Implementing IPv6 457
IPv6 Address Assignment 457
Dynamic Assignment of the Interface ID with EUI-64 457
Discovering the IPv6 Prefix with SLAAC 459
Dynamic Configuration Using Stateful DHCP 460
IPv6 Transition and Coexistence 461
Dual Stack 462
Tunneling IPv6 Inside IPv4 462
Exam Preparation Tasks 464
Review All the Key Topics 464
Complete the Tables and Lists from Memory 464
Definitions of Key Terms 464
Answers to Earlier Practice Problems 464
Part IV Review 466
Part V: IPv4 Routing 471
Chapter 18 IPv4 Routing Concepts 473
Do I Know This Already? Quiz 473
Foundation Topics 475
IP Routing 475
IPv4 Routing Process Reference 475
An Example of IP Routing 478
Host Forwards the IP Packet to the Default Router (Gateway) 478
Routing Step 1: Decide Whether to Process the Incoming Frame 479
Routing Step 2: Deencapsulation of the IP Packet 480
Routing Step 3: Choosing Where to Forward the Packet 480
Routing Step 4: Encapsulating the Packet in a New Frame 481
Routing Step 5: Transmitting the Frame 482
Internal Processing on Cisco Routers 482
Potential Routing Performance Issues 483
Cisco Router Fast Switching and CEF 483
Cisco Nexus Switch Operations with Routing 484
Exam Preparation Tasks 488
Review All the Key Topics 488
Complete the Tables and Lists from Memory 488
Definitions of Key Terms 488
Chapter 19 Cisco Nexus IPv4 Routing Configuration 491
Do I Know This Already? Quiz 491
Foundation Topics 494
Configuring Connected Routes on Cisco Nexus Switches 494
Direct and Local Routes and the ip address Command 494
Routing Between Subnets on VLANs 497
Configuring Routing to VLANs Using a Layer 3 Switch 497
Configuring Static Routes 499
Static Route Configuration 499
Static Default Routes 501
Exam Preparation Tasks 502
Review All the Key Topics 502
Complete the Tables and Lists from Memory 502
Definitions of Key Terms 502
Command Reference to Check Your Memory 502
Chapter 20 IPv4 Routing Protocol Concepts 505
Do I Know This Already? Quiz 505
Foundation Topics 508
Introduction to Routing Protocols 508
History of Interior Gateway Protocols 508
Comparing IGPs 509
Distance Vector Basics 511
The Concept of a Distance and a Vector 511
Full Update Messages and Split Horizon 512
Monitoring Neighbor State with Periodic RIP Updates 513
Split Horizon 513
Route Poisoning 514
RIP Concepts and Operation 515
Features of Both RIPv1 and RIPv2 515
Differences Between RIPv1 and RIPv2 516
EIGRP Concepts and Operation 517
EIGRP Maintains Neighbor Status Using Hello 518
EIGRP Topology and the Metric Calculation 518
EIGRP Convergence 519
EIGRP Summary 521
Understanding the OSPF Link-State Routing Protocol 521
OSPF Comparisons with EIGRP 521
Building the OSPF LSDB and Creating IP Routes 522
Topology Information and LSAs 522
Applying Dijkstra SPF Math and OSPF Metrics to Find the Best Routes 524
Scaling OSPF Through Hierarchical Design 525
Exam Preparation Tasks 528
Review All the Key Topics 528
Definitions of Key Terms 528
Chapter 21 Nexus Routing Protocol Configuration 531
Do I Know This Already? Quiz 531
Foundation Topics 533
RIP Version 2 Configuration on NX-OS 536
EIGRP Configuration on NX-OS 541
OSPF Configuration on NX-OS 546
Exam Preparation Tasks 551
Review All the Key Topics 551
Definitions of Key Terms 551
Command Reference to Check Your Memory 551
Chapter 22 IPv4 Access Control Lists on Cisco Nexus Switches 555
Do I Know This Already? Quiz 555
Foundation Topics 557
IPv4 Access Control List Basics 557
ACL Location and Direction 557
Matching Packets 558
Taking Action When a Match Occurs 559
Types of IP ACLs 559
List Logic with IP ACLs 560
Matching Logic and Command Syntax 562
Matching TCP and UDP Port Numbers 562
Implementing Cisco Nexus IPv4 ACLs 566
ACL Example 1 566
ACL Example 2 567
Practice Cisco Nexus IPv4 ACLs 568
Practice Building access-list Commands 568
Exam Preparation Tasks 570
Review All the Key Topics 570
Definitions of Key Terms 570
Appendix H Practice Problems 570
Command Reference to Check Your Memory 570
Part V Review 572
Part VI: Final Preparation 577
Chapter 23 Final Review 579
Advice About the Exam Event 579
Learn the Question Types Using the Cisco Certification Exam Tutorial 579
Think About Your Time Budget Versus Numbers of Questions 580
A Suggested Time-Check Method 581
Miscellaneous Pre-Exam Suggestions 582
Exam-Day Advice 582
Exam Review 583
Practice Subnetting and Other Math-Related Skills 583
Take Practice Exams 585
Practicing Taking the DCICN Exam 585
Advice on How to Answer Exam Questions 586
Taking Other Practice Exams 587
Find Knowledge Gaps Through Question Review 588
Practice Hands-On CLI Skills 591
Review Mind Maps from Part Review 591
Other Study Tasks 591
Final Thoughts 591
Part VII: Appendices 593
Appendix A Answers to the Do I Know This Already? Quizzes 595
Appendix B DCICN Exam Updates 613
Appendix C Numeric Reference Tables 615
Appendix D Nexus Lab Guide 623
DVD-only Appendices
Appendix E Practice for Chapter 14: Analyzing Classful IPv4 Networks
Appendix F Practice for Chapter 15: Analyzing Subnet Masks
Appendix G Practice for Chapter 16: Analyzing Existing Subnets
Appendix H Practice for Chapter 22: IPv4 Access Control Lists on Cisco Nexus Switches
Appendix I Memory Tables
Appendix J Memory Tables Answer Key
Glossary
9781587204548 TOC 10/15/2014
