Introduction xxv Assessment Test l Part I ICND1 1 Chapter 1 Internetworking 3 Internetworking Basics 4 Internetworking Models 13 The Layered Approach 13 Advantages of Reference Models 14 The OSI Reference Model 15 The Application Layer 17 The Presentation Layer 18 The Session Layer 18 The Transport Layer 18 The Network Layer 24 The Data Link Layer 26 The Physical Layer 29 Summary 31 Exam Essentials 31 Written Labs 32 Written Lab 1.1: OSI Questions 32 Written Lab 1.2: Defining the OSI Layers and Devices 34 Written Lab 1.3: Identifying Collision and Broadcast Domains 34 Review Questions 36 Chapter 2 Ethernet Networking and Data Encapsulation 41 Ethernet Networks in Review 42 Collision Domain 43 Broadcast Domain 44 CSMA/CD 45 Half- and Full-Duplex Ethernet 47 Ethernet at the Data Link Layer 49 Ethernet at the Physical Layer 55 Ethernet Cabling 59 Straight-Through Cable 59 Crossover Cable 60 Rolled Cable 62 Fiber Optic 64 Data Encapsulation 66 The Cisco Three-Layer Hierarchical Model 69 The Core Layer 71 The Distribution Layer 71 The Access Layer 72 Summary 72 Exam Essentials 73 Written Labs 74 Written Lab 2.1: Binary/Decimal/Hexadecimal Conversion 74 Written Lab 2.2: CSMA/CD Operations 77 Written Lab 2.3: Cabling 78 Written Lab 2.4: Encapsulation 78 Review Questions 79 Chapter 3 Introduction to TCP/IP 85 Introducing TCP/IP 86 A Brief History of TCP/IP 87 TCP/IP and the DoD Model 87 The Process/Application Layer Protocols 89 The Host-to-Host or Transport Layer Protocols 99 The Internet Layer Protocols 108 IP Addressing 116 IP Terminology 116 The Hierarchical IP Addressing Scheme 117 Private IP Addresses (RFC 1918) 122 IPv4 Address Types 123 Layer 2 Broadcasts 124 Layer 3 Broadcasts 124 Unicast Address 125 Multicast Address 126 Summary 127 Exam Essentials 127 Written Labs 129 Written Lab 3.1: TCP/IP 129 Written Lab 3.2: Mapping Applications to the DoD Model 129 Review Questions 131 Chapter 4 Easy Subnetting 135 Subnetting Basics 136 How to Create Subnets 138 Subnet Masks 138 Classless Inter-Domain Routing (CIDR) 140 IP Subnet-Zero 142 Subnetting Class C Addresses 142 Subnetting Class B Addresses 154 Subnetting Class A Addresses 163 Summary 166 Exam Essentials 166 Written Labs 167 Written Lab 4.1: Written Subnet Practice #1 167 Written Lab 4.2: Written Subnet Practice #2 168 Written Lab 4.3: Written Subnet Practice #3 169 Review Questions 170 Chapter 5 VLSMs, Summarization, and Troubleshooting TCP/IP 175 Variable Length Subnet Masks (VLSMs) 176 VLSM Design 178 Implementing VLSM Networks 179 Summarization 186 Troubleshooting IP Addressing 189 Determining IP Address Problems 192 Summary 196 Exam Essentials 197 Written Lab 5 198 Lab 5.1: Summarization Practice 198 Review Questions 199 Chapter 6 Cisco s Internetworking Operating System (IOS) 205 The IOS User Interface 206 Cisco IOS 206 Connecting to a Cisco IOS Device 207 Bringing Up a Switch 209 Command-Line Interface (CLI) 209 Entering the CLI 210 Overview of Router Modes 210 CLI Prompts 211 Editing and Help Features 213 Administrative Configurations 218 Hostnames 219 Banners 219 Setting Passwords 221 Encrypting Your Passwords 227 Descriptions 229 Router and Switch Interfaces 231 Bringing Up an Interface 234 Viewing, Saving, and Erasing Configurations 240 Deleting the Configuration and Reloading the Device 242 Verifying Your Configuration 242 Summary 255 Exam Essentials 256 Written Lab 6: IOS Understanding 259 Hands-on Labs 259 Hands-on Lab 6.1: Erasing an Existing Configuration 260 Hands-on Lab 6.2: Exploring User, Privileged, and Configuration Modes 260 Hands-on Lab 6.3: Using the Help and Editing Features 261 Hands-on Lab 6.4: Saving a Configuration 262 Hands-on Lab 6.5: Setting Passwords 263 Hands-on Lab 6.6: Setting the Hostname, Descriptions, IP Address, and Clock Rate 265 Review Questions 267 Chapter 7 Managing a Cisco Internetwork 273 The Internal Components of a Cisco Router and Switch 274 The Router and Switch Boot Sequence 275 Backing Up and Restoring the Cisco Configuration 276 Backing Up the Cisco Configuration 277 Restoring the Cisco Configuration 279 Erasing the Configuration 279 Configuring DHCP 280 DHCP Relay 281 Verifying DHCP on Cisco IOS 282 Syslog 283 Configuring and Verifying Syslog 285 Network Time Protocol (NTP) 288 Exploring Connected Devices Using CDP and LLDP 289 Getting CDP Timers and Holdtime Information 290 Gathering Neighbor Information 291 Documenting a Network Topology Using CDP 295 Using Telnet 298 Telnetting into Multiple Devices Simultaneously 300 Checking Telnet Connections 300 Checking Telnet Users 301 Closing Telnet Sessions 301 Resolving Hostnames 302 Building a Host Table 302 Using DNS to Resolve Names 304 Checking Network Connectivity and Troubleshooting 306 Using the ping Command 306 Using the traceroute Command 307 Debugging 308 Using the show processes Command 310 Summary 311 Exam Essentials 311 Written Labs 7 313 Written Lab 7.1: IOS Management 313 Written Lab 7.2: Router Memory 314 Hands-on Labs 314 Hands-on Lab 7.1: Backing Up the Router Configuration 315 Hands-on Lab 7.2: Using the Cisco Discovery Protocol (CDP) 315 Hands-on Lab 7.3: Using Telnet 316 Hands-on Lab 7.4: Resolving Hostnames 317 Review Questions 319 Chapter 8 Managing Cisco Devices 323 Managing the Configuration Register 324 Understanding the Configuration Register Bits 324 Checking the Current Configuration Register Value 326 Boot System Commands 327 Recovering Passwords 328 Backing Up and Restoring the Cisco IOS 331 Verifying Flash Memory 332 Backing Up the Cisco IOS 333 Restoring or Upgrading the Cisco Router IOS 334 Using the Cisco IOS File System (Cisco IFS) 337 Licensing 341 Right-To-Use Licenses (Evaluation Licenses) 344 Backing Up and Uninstalling the License 347 Summary 348 Exam Essentials 348 Written Lab 8 349 Written Lab 8.1: IOS Management 350 Hands-on Labs 350 Hands-on Lab 8.1: Backing Up Your Router IOS 350 Hands-on Lab 8.2: Upgrading or Restoring Your Router IOS 351 Review Questions 352 Chapter 9 IP Routing 357 Routing Basics 359 The IP Routing Process 361 The Cisco Router Internal Process 366 Testing Your IP Routing Understanding 367 Configuring IP Routing 372 Corp Configuration 373 SF Configuration 375 LA Configuration 379 Configuring IP Routing in Our Network 381 Static Routing 382 Default Routing 387 Dynamic Routing 390 Routing Protocol Basics 390 Routing Information Protocol (RIP) 392 Configuring RIP Routing 393 Holding Down RIP Propagations 396 Summary 399 Exam Essentials 399 Written Lab 9 400 Hands-on Labs 401 Hands-on Lab 9.1: Creating Static Routes 402 Hands-on Lab 9.2: Configuring RIP Routing 403 Review Questions 405 Chapter 10 Layer 2 Switching 411 Switching Services 412 Three Switch Functions at Layer 2 413 Port Security 417 Configuring Catalyst Switches 422 Catalyst Switch Configuration 423 Verifying Cisco Catalyst Switches 430 Summary 433 Exam Essentials 433 Written Lab 10 434 Hands-on Labs 434 Lab 10.1: Configuring Layer 2 Switches 435 Lab 10.2: Verifying Layer 2 Switches 436 Lab 10.3: Configuring Port Security 437 Review Questions 438 Chapter 11 VLANs and Inter-VLAN Routing 443 VLAN Basics 444 Broadcast Control 447 Security 448 Flexibility and Scalability 448 Identifying VLANs 449 Frame Tagging 451 VLAN Identification Methods 452 Routing between VLANs 454 Configuring VLANs 456 Assigning Switch Ports to VLANs 459 Configuring Trunk Ports 461 Configuring Inter-VLAN Routing 465 Summary 472 Exam Essentials 472 Written Lab 11 473 Hands-on Labs 473 Hands-on Lab 11.1: Configuring and Verifying VLANs 474 Hands-on Lab 11.2: Configuring and Verifying Trunk Links 474 Hands-on Lab 11.3: Configuring Router on a Stick Routing 475 Hands-on Lab 11.4: Configuring IVR with a Layer 3 Switch 476 Review Questions 477 Chapter 12 Security 483 Perimeter, Firewall, and Internal Routers 484 Introduction to Access Lists 485 Mitigating Security Issues with ACLs 488 Standard Access Lists 489 Wildcard Masking 490 Standard Access List Example 492 Controlling VTY (Telnet/SSH) Access 496 Extended Access Lists 497 Extended Access List Example 1 501 Extended Access List Example 2 503 Extended Access List Example 3 504 Named ACLs 505 Remarks 507 Monitoring Access Lists 508 Summary 510 Exam Essentials 511 Written Lab 12 511 Hands-on Labs 512 Hands-on Lab 12.1: Standard IP Access Lists 513 Hands-on Lab 12.2: Extended IP Access Lists 514 Review Questions 517 Chapter 13 Network Address Translation (NAT) 521 When Do We Use NAT? 522 Types of Network Address Translation 524 NAT Names 524 How NAT Works 525 Static NAT Configuration 527 Dynamic NAT Configuration 527 PAT (Overloading) Configuration 528 Simple Verification of NAT 529 Testing and Troubleshooting NAT 529 Summary 535 Exam Essentials 535 Written Lab 13 535 Hands-on Labs 536 Lab 13.1: Preparing for NAT 537 Lab 13.2: Configuring Dynamic NAT 538 Lab 13.3: Configuring PAT 540 Review Questions 542 Chapter 14 Internet Protocol Version 6 (IPv6) 547 Why Do We Need IPv6? 549 The Benefits and Uses of IPv6 549 IPv6 Addressing and Expressions 551 Shortened Expression 551 Address Types 552 Special Addresses 554 How IPv6 Works in an Internetwork 555 Manual Address Assignment 555 Stateless Autoconfiguration (eui-64) 556 DHCPv6 (Stateful) 559 IPv6 Header 559 ICMPv6 561 IPv6 Routing Protocols 565 Static Routing with IPv6 565 Configuring IPv6 on Our Internetwork 566 Configuring Routing on Our Internetwork 569 Summary 572 Exam Essentials 573 Written Labs 14 573 Written Lab 14.1 573 Written Lab 14.2 574 Hands-on Labs 574 Hands-on Lab 14.1: Manual and Stateful Autoconfiguration 574 Hands-on Lab 14.2: Static and Default Routing 576 Review Questions 577 Part II ICND2 581 Chapter 15 Enhanced Switched Technologies 583 VLAN Review 584 Assigning Switch Ports to VLANs 587 Configuring Trunk Ports 589 VLAN Trunking Protocol (VTP) 593 VTP Modes of Operation 594 VTP Pruning 596 Configuring VTP 597 Troubleshooting VTP 598 Spanning Tree Protocol (STP) 602 Spanning-Tree Terms 603 Spanning-Tree Operations 607 Types of Spanning-tree Protocols 610 Common Spanning Tree 610 Per-VLAN Spanning Tree+ 611 Modifying and Verifying the Bridge ID 618 Spanning-Tree Failure Consequences 623 PortFast and BPDU Guard 625 BPDU Guard 627 EtherChannel 629 Configuring and Verifying Port Channels 630 Summary 634 Exam Essentials 635 Written Lab 15 635 Hands-on Labs 636 Hands-on Lab 15.1: Verifying STP and Finding Your Root Bridge 637 Hands-on Lab 15.2: Configuring and Verifying Your Root Bridge 638 Hands-on Lab 15.3: Configuring PortFast and BPDU Guard 640 Hands-on Lab 15.4: Configuring and Verifying EtherChannel 641 Review Questions 643 Chapter 16 Network Device Management and Security 649 Mitigating Threats at the Access Layer 650 External Authentication Options 653 RADIUS 653 TACACS+ 654 SNMP 655 Management Information Base (MIB) 656 Configuring SNMP 657 Client Redundancy Issues 659 Introducing First Hop Redundancy Protocols (FHRPs) 661 Hot Standby Router Protocol (HSRP) 662 Virtual MAC Address 664 HSRP Timers 665 Group Roles 667 Configuring and Verifying HSRP 669 Summary 675 Exam Essentials 675 Written Lab 16 676 Review Questions 677 Chapter 17 Enhanced IGRP 681 EIGRP Features and Operations 682 Neighbor Discovery 683 Reliable Transport Protocol (RTP) 688 Diffusing Update Algorithm (DUAL) 689 Route Discovery and Maintenance 689 Configuring EIGRP 690 VLSM Support and Summarization 693 Controlling EIGRP Traffic 696 Split Horizon 707 Verifying and Troubleshooting EIGRP 709 Troubleshooting Example with EIGRP 715 Simple Troubleshooting EIGRP for the CCNA 725 EIGRPv6 727 Summary 732 Exam Essentials 733 Written Lab 17 733 Hands-on Labs 734 Hands-on Lab 17.1: Configuring and Verifying EIGRP 734 Hands-on Lab 17.2: Configuring and Verifying EIGRPv6 735 Review Questions 737 Chapter 18 Open Shortest Path First (OSPF) 745 Open Shortest Path First (OSPF) Basics 746 OSPF Terminology 749 OSPF Operation 751 Configuring OSPF 753 Enabling OSPF 753 Configuring OSPF Areas 754 Configuring Our Network with OSPF 757 OSPF and Loopback Interfaces 762 Configuring Loopback Interfaces 763 Verifying OSPF Configuration 765 The show ip ospf Command 766 The show ip ospf database Command 767 The show ip ospf interface Command 768 The show ip ospf neighbor Command 769 The show ip protocols Command 770 Summary 771 Exam Essentials 771 Written Lab 18 772 Hands-on Labs 772 Hands-on Lab 18.1: Enabling the OSPF Process 773 Hands-on Lab 18.2: Configuring OSPF Interfaces 774 Hands-on Lab 18.3: Verifying OSPF Operation 775 Review Questions 776 Chapter 19 Multi-Area OSPF 783 OSPF Scalability 784 Categories of Multi-area Components 786 Adjacency Requirements 786 OSPF Router Roles 787 Link-State Advertisements 788 OSPF Hello Protocol 790 Neighbor States 791 Basic Multi-area Configuration 793 Verifying and Troubleshooting Multi-area OSPF Networks 796 The show ip ospf Command 797 The show ip ospf interface Command 798 The show ip protocols Command 801 The show ip route Command 801 The show ip ospf database Command 802 Troubleshooting OSPF Scenario 804 Simple Troubleshooting OSPF for the CCNA 812 OSPFv3 814 Verifying OSPFv3 816 Summary 819 Exam Essentials 819 Written Lab 19 820 Hands-on Labs 820 Hands-on Lab 19.1: Configuring and Verifying OSPF Multi-Area 821 Hands-on Lab 19.2: Configuring and Verifying OSPFv3 824 Review Questions 826 Chapter 20 Troubleshooting IP, IPv6, and VLANs 831 Troubleshooting IP Network Connectivity 832 Using IP SLA for Troubleshooting 843 Using SPAN for Troubleshooting 845 Configuring and Verifying Extended Access Lists 847 Troubleshooting IPv6 Network Connectivity 850 ICMPv6 850 Troubleshooting IPv6 Extended Access Lists 858 Troubleshooting VLAN Connectivity 862 VLAN Troubleshooting 862 Trunk Troubleshooting 867 Summary 874 Exam Essentials 875 Written Lab 20 875 Review Questions 877 Chapter 21 Wide Area Networks 881 Introduction to Wide Area Networks 882 WAN Topology Options 883 Defining WAN Terms 885 WAN Connection Bandwidth 886 WAN Connection Types 887 WAN Support 888 Cisco Intelligent WAN (IWAN) 891 Cabling the Serial Wide Area Network 894 Serial Transmission 894 Data Terminal Equipment and Data Communication Equipment 895 High-Level Data-Link Control (HDLC) Protocol 896 Point-to-Point Protocol (PPP) 898 Link Control Protocol (LCP) Configuration Options 899 PPP Session Establishment 900 PPP Authentication Methods 901 Configuring PPP on Cisco Routers 901 Configuring PPP Authentication 901 Verifying and Troubleshooting Serial Links 902 Multilink PPP (MLP) 907 PPP Client (PPPoE) 911 Configuring a PPPoE Client 912 Virtual Private Networks 913 Benefits of VPNs 914 Enterprise- and Provider-Managed VPNs 915 Introduction to Cisco IOS IPsec 917 IPsec Transforms 918 GRE Tunnels 919 GRE over IPsec 920 Configuring GRE Tunnels 921 Verifying GRP Tunnels 923 Single-Homed EBGP 925 Protocol Comparison and Overview 926 Configuring and Verifying EBGP 929 Verifying EBGP 931 Summary 934 Exam Essentials 934 Written Lab 21 935 Hands-on Labs 935 Hands-on Lab 21.1: Configuring PPP Encapsulation and Authentication 936 Hands-on Lab 21.2: Configuring and Monitoring HDLC 937 Hands-on Lab 21.3: Configuring a GRE Tunnel 938 Review Questions 941 Chapter 22 Evolution of Intelligent Networks 947 Switch Stacking 948 Cloud Computing and Its Effect on the Enterprise Network 950 Service Models 952 Overview of Network Programmability in Enterprise Network 953 Application Programming Interfaces (APIs) 954 Southbound APIs 955 Northbound APIs 956 Cisco APIC-EM 957 Using APIC-EM for Path Tracing 959 Cisco Intelligent WAN 960 Quality of Service 962 Traffic Characteristics 962 Trust Boundary 964 QoS Mechanisms 965 Classification and Marking 965 Policing, Shaping, and Re-Marking 966 Tools for Managing Congestion 967 Tools for Congestion Avoidance 970 Summary 971 Exam Essentials 971 Written Lab 22 971 Review Questions 973 Appendix A Answers to Written Labs 977 Chapter 1: Internetworking 978 Written Lab 1.1: OSI Questions 978 Written Lab 1.2: Defining the OSI Layers and Devices 979 Written Lab 1.3: Identifying Collision and Broadcast Domains 979 Chapter 2: Ethernet Networking and Data Encapsulation 980 Written Lab 2.1: Binary/Decimal/Hexadecimal Conversion 980 Written Lab 2.2: CSMA/CD Operations 982 Written Lab 2.3: Cabling 982 Written Lab 2.4: Encapsulation 982 Chapter 3: Introduction to TCP/IP 983 Written Lab 3.1: TCP/IP 983 Written Lab 3.2: Mapping Applications to the DoD Model 983 Chapter 4: Easy Subnetting 984 Written Lab 4.1: Written Subnet Practice #1 984 Written Lab 4.2: Written Subnet Practice #2 985 Written Lab 4.3: Written Subnet Practice #3 985 Chapter 5: VLSMs, Summarization and Troubleshooting TCP/IP 986 Chapter 6: Cisco s Internetworking Operating System (IOS) 986 Written Lab 6: Cisco IOS 986 Chapter 7: Managing a Cisco Internetwork 987 Written Lab 7.1: IOS Management 987 Written Lab 7.2: Router Memory 987 Chapter 8: Managing Cisco Devices 988 Written Lab 8.1: IOS Management 988 Chapter 9: IP Routing 988 Chapter 10: Layer 2 Switching 989 Chapter 11: VLANs and InterVLAN Routing 989 Chapter 12: Security 990 Chapter 13: Network Address Translation (NAT) 991 Chapter 14: Internet Protocol Version 6 (IPv6) 991 Written Lab 14.1: IPv6 Foundation 991 Written Lab 14.2: EUI-64 Format 992 Chapter 15: Enhanced Switched Technologies 992 Written Lab 15 992 Chapter 16: Network Device Management and Security 993 Written Lab 16 993 Chapter 17: Enhanced IGRP 993 Written Lab 17 993 Chapter 18: Open Shortest Path First (OSPF) 994 Written Lab 18 994 Chapter 19: Multi-Area OSPF 994 Written Lab 19 994 Chapter 20: Troubleshooting IP, IPv6, and VLANs 995 Written Lab 20 995 Chapter 21: Wide Area Networks 995 Written Lab 21 995 Chapter 22: Evolution of Intelligent Networks 996 Written Lab 22 996 Appendix B Answers to Review Questions 997 Chapter 1: Internetworking 998 Chapter 2: Ethernet Networking and Data Encapsulation 1000 Chapter 3: Introduction to TCP/IP 1002 Chapter 4: Easy Subnetting 1003 Chapter 5: VLSMs, Summarization, and Troubleshooting TCP/IP 1005 Chapter 6: Cisco s Internetworking Operating System (IOS) 1007 Chapter 7: Managing a Cisco Internetwork 1009 Chapter 8: Managing Cisco Devices 1010 Chapter 9: IP Routing 1012 Chapter 10: Layer 2 Switching 1013 Chapter 11: VLANs and InterVLAN Routing 1015 Chapter 12: Security 1017 Chapter 13: Network Address Translation (NAT) 1019 Chapter 14: Internet Protocol Version 6 (IPv6) 1020 Chapter 15: Enhanced Switched Technologies 1022 Chapter 16: Network Device Management and Security 1024 Chapter 17: Enhanced IGRP 1025 Chapter 18: Open Shortest Path First (OSPF) 1027 Chapter 19: Multi-Area OSPF 1029 Chapter 20: Troubleshooting IP, IPv6, and VLANs 1031 Chapter 21: Wide Area Networks 1032 Chapter 22: Evolution of Intelligent Networks 1033 Appendix C Disabling and Configuring Network Services 1037 Blocking SNMP Packets 1038 Disabling Echo 1038 Turning off BootP and Auto-Config 1039 Disabling the HTTP Interface 1040 Disabling IP Source Routing 1040 Disabling Proxy ARP 1040 Disabling Redirect Messages 1040 Disabling the Generation of ICMP Unreachable Messages 1041 Disabling Multicast Route Caching 1041 Disabling the Maintenance Operation Protocol (MOP) 1041 Turning Off the X.25 PAD Service 1042 Enabling the Nagle TCP Congestion Algorithm 1042 Logging Every Event 1042 Disabling Cisco Discovery Protocol 1043 Disabling the Default Forwarded UDP Protocols 1043 Cisco s auto secure 1044 Index 1047
