Connecting Networks Companion Guide

by Cisco Networking Academy

• ISBN13: 9781587133329
• ISBN10: 1587133326
• Edition: 1st
• Format: Hardcover
• Copyright: 2014-05-02
• Publisher: Cisco Press

Summary

Connecting Networks Companion Guide is the official supplemental textbook for the Connecting Networks course in the Cisco® Networking Academy® CCNA® Routing and Switching curriculum.

 

This course discusses the WAN technologies and network services required by converged applications in a complex network. The course allows you to understand the selection criteria of network devices and WAN technologies to meet network requirements. You will learn how to configure and troubleshoot network devices and resolve common issues with data link protocols. You will also develop the knowledge and skills needed to implement IPSec and virtual private network (VPN) operations in a complex network.

 

The Companion Guide is designed as a portable desk reference to use anytime, anywhere to reinforce the material from the course and organize your time.

 

The book’s features help you focus on important concepts to succeed in this course:

 

• Chapter objectives–Review core concepts by answering the focus questions listed at the beginning of each chapter.
• Key terms–Refer to the lists of networking vocabulary introduced and highlighted in context in each chapter. 
• Glossary–Consult the comprehensive Glossary with 195 terms. 
• Summary of Activities and Labs–Maximize your study time with this complete list of all associated practice exercises at the end of each chapter. 
• Check Your Understanding–Evaluate your readiness with the end-of-chapter questions that match the style of questions you see in the online course quizzes. The answer key explains each answer.
• How To–Look for this icon to study the steps you need to learn to perform certain tasks.
• Interactive Activities–Reinforce your understanding of topics with all the different exercises from the online course identified throughout the book with this icon.
• Videos–Watch the videos embedded within the online course.
• Packet Tracer Activities–Explore and visualize networking concepts using Packet Tracer exercises interspersed throughout the chapters.
• Hands-on Labs–Work through all the course labs and Class Activities that are included in the course and published in the separate Lab Manual.

 

 

Author Biography

Rick Graziani teaches computer science and computer networking courses at Cabrillo College in Aptos, California. Prior to teaching, Rick worked in the informationtechnology field for Santa Cruz Operation, Tandem Computers, and Lockheed Missiles and Space Corporation. He holds an M.A. in Computer Science and Systems Theory from California State University Monterey Bay. Rick is also a member of the Curriculum Development team for the Cisco Networking Academy since 1999.

 

Rick has authored multiple books for Cisco Press and multiple online courses for the Cisco Networking Academy. Rick is the author of the Cisco Press book IPv6 Fundamentals and has presented on IPv6 at several Cisco Academy conferences. He is the coauthor of the Cisco Press book Routing Protocols Companion Guide.

 

When Rick is not working, he is most likely surfing at one of his favorite Santa Cruz surf breaks.

 

Bob Vachon is a professor in the Computer Systems Technology program at Cambrian College in Sudbury, Ontario, Canada, where he teaches networking infrastructure courses. He has over 30 years of work and teaching experience in the computer networking and information technology field.

 

Since 2001, Bob has collaborated as team lead, lead author, and subject matter expert on various CCNA, CCNA-S, and CCNP projects for Cisco and the Cisco Networking Academy. He also authored the CCNA Accessing the WAN Companion Guide and the CCNA Security (640-554) Portable Command Guide. He is the coauthor of the Cisco Press book Routing Protocols Companion Guide.

 

In his downtime, Bob enjoys playing the guitar, shooting darts or pool, and either working in his gardens or white-water canoe tripping.

Table of Contents

    Introduction xix

Chapter 1: Hierarchical Network Designs 1

    Objectives 1

    Key Terms 1

    Introduction (1.0.1.1) 2

    Hierarchical Network Design Overview (1.1) 2

        Enterprise Network Campus Design (1.1.1) 2

            Network Requirements (1.1.1.1) 3

            Structured Engineering Principles (1.1.1.2) 4

        Hierarchical Network Design (1.1.2) 4

            Network Hierarchy (1.1.2.1) 4

            The Access Layer (1.1.2.2) 6

        The Distribution Layer (1.1.2.3) 7

        The Core Layer (1.1.2.4) 9

            Two-Tier Collapsed Core Design (1.1.2.5) 10

    Cisco Enterprise Architecture (1.2) 10

        Modular Design (1.2.1.1) 11

        Modules in the Enterprise Architecture (1.2.1.2) 12

    Cisco Enterprise Architecture Model (1.2.2) 14

        Cisco Enterprise Architecture Model (1.2.2.1) 14

        Cisco Enterprise Campus (1.2.2.2) 15

        Cisco Enterprise Edge (1.2.2.3) 17

        Service Provider Edge (1.2.2.4) 18

        Remote Functional Area (1.2.2.5) 21

            Enterprise Branch 21

            Enterprise Teleworker 22

            Enterprise Data Center 22

    Evolving Network Architectures (1.3) 22

        IT Challenges (1.3.1.1) 22

        Emerging Enterprise Architectures (1.3.1.2) 23

    Emerging Network Architectures (1.3.2) 24

        Cisco Borderless Networks (1.3.2.1) 24

        Collaboration Architecture (1.3.2.2) 25

        Data Center and Virtualization (1.3.2.3) 26

        Expanding the Network (1.3.2.4) 27

    Summary (1.4) 29

    Practice 30

        Class Activities 30

        Packet Tracer Activities 30

    Check Your Understanding Questions 31

Chapter 2: Connecting the WAN 35

    Objectives 35

    Key Terms 35

    Introduction (2.0.1.1) 37

    WAN Technologies Overview (2.1) 37

        Why a WAN? (2.1.1.1) 37

        Are WANs Necessary? (2.1.1.2) 38

        Evolving Networks (2.1.1.3) 39

        Small Office (2.1.1.4) 39

        Campus Network (2.1.1.5) 40

        Branch Networks (2.1.1.6) 42

        Distributed Network (2.1.1.7) 43

    WAN Operations (2.1.2) 44

        WANs in the OSI Model (2.1.2.1) 44

        Common WAN Terminology (2.1.2.2) 45

        WAN Devices (2.1.2.3) 47

        Circuit-Switched Networks (2.1.2.4) 48

        Packet-Switched Networks (2.1.2.5) 50

    Selecting a WAN Technology (2.2) 51

        WAN Link Connection Options (2.2.1.1) 51

        Service Provider Network Infrastructure (2.2.1.2) 52

    Private WAN Infrastructures (2.2.2) 54

        Leased Lines (2.2.2.1) 54

        Dialup (2.2.2.2) 55

        ISDN (2.2.2.3) 56

        Frame Relay (2.2.2.4) 58

        ATM (2.2.2.5) 59

        Ethernet WAN (2.2.2.6) 60

        MPLS (2.2.2.7) 62

        VSAT (2.2.2.8) 63

    Public WAN Infrastructure (2.2.3) 64

        DSL (2.2.3.1) 64

        Cable (2.2.3.2) 65

        Wireless (2.2.3.3) 66

        3G/4G Cellular (2.2.3.4) 67

        VPN Technology (2.2.3.5) 68

    Selecting WAN Services (2.2.4) 70

        Choosing a WAN Link Connection (2.2.4.1, 2.2.4.2) 70

            What Is the Purpose of the WAN? 70

            What Is the Geographic Scope? 70

            What Are the Traffic Requirements? 71

    Summary (2.3) 73

    Practice 74

        Class Activities 74

        Labs 74

    Check Your Understanding Questions 74

Chapter 3: Point-to-Point Connections 79

    Objectives 79

    Key Terms 79

    Introduction (3.0.1.1) 80

    Serial Point-to-Point Overview (3.1) 80

        Serial Communications (3.1.1) 81

            Serial and Parallel Ports (3.1.1.1) 81

            Serial Communication (3.1.1.2) 82

            Point-to-Point Communication Links (3.1.1.3) 84

            Time-Division Multiplexing (3.1.1.4) 85

            Statistical Time-Division Multiplexing (3.1.1.5) 86

            TDM Examples — Sonet and SDM (3.1.1.6) 87

            Demarcation Point (3.1.1.7) 88

            DTE-DCE (3.1.1.8) 90

            Serial Cables (3.1.1.9) 91

            Serial Bandwidth (3.1.1.10) 94

        HDLC Encapsulation (3.1.2) 96

            WAN Encapsulation Protocols (3.1.2.1) 96

            HDLC Encapsulation (3.1.2.2) 97

            HDLC Frame Types (3.1.2.3) 98

            Configuring HDLC Encapsulation (3.1.2.4) 100

            Troubleshooting a Serial Interface (3.1.2.5) 100

    PPP Operation (3.2) 104

        Benefits of PPP (3.2.1) 104

            Introducing PPP (3.2.1.1) 104

            Advantages of PPP (3.2.1.2) 106

        LCP and NCP (3.2.2) 106

            PPP Layered Architecture (3.2.2.1) 106

            PPP — Link Control Protocol (LCP) (3.2.2.2) 107

            PPP — Network Control Protocol (NCP) (3.2.2.3) 108

            PPP Frame Structure (3.2.2.4) 108

        PPP Sessions (3.2.3) 109

            Establishing a PPP Session (3.2.3.1) 110

            LCP Operation (3.2.3.2) 111

            LCP Packet (3.2.3.3) 113

            PPP Configuration Options (3.2.3.4) 115

            NCP Explained (3.2.3.5) 117

    Configure PPP (3.3) 118

        Configure PPP (3.3.1) 118

            PPP Configuration Options (3.3.1.1) 119

            PPP Basic Configuration Command (3.3.1.2) 120

            PPP Compression Commands (3.3.1.3) 121

            PPP Link Quality Monitoring Command (3.3.1.4) 122

            PPP Multilink Commands (3.3.1.5) 123

            Verifying PPP Configuration (3.3.1.6) 125

        PPP Authentication (3.3.2) 126

            PPP Authentication Protocols (3.3.2.1) 127

            Password Authentication Protocol (PAP) (3.3.2.2) 127

            Challenge Handshake Authentication Protocol (CHAP) (3.3.2.3) 129

            PPP Encapsulation and Authentication Process (3.3.2.4) 131

            Configuring PPP Authentication (3.3.2.5) 134

            Configuring PPP with Authentication (3.3.2.6) 136

    Troubleshoot WAN Connectivity (3.4) 138

        Troubleshoot PPP (3.4.1) 138

            Troubleshooting PPP Serial Encapsulation (3.4.1.1) 138

            Debug PPP (3.4.1.2) 140

            Troubleshooting a PPP Configuration with Authentication (3.4.1.3) 142

    Summary (3.5) 145

    Practice 146

        Class Activities 146

        Labs 146

        Packet Tracer Activities 146

    Check Your Understanding Questions 147

Chapter 4: Frame Relay 153

    Objectives 153

    Key Terms 153

    Introduction (4.0.1.1) 154

    Introduction to Frame Relay (4.1) 154

        Benefits of Frame Relay (4.1.1) 155

            Introducing Frame Relay (4.1.1.1) 155

            Benefits of Frame Relay WAN Technology (4.1.1.2) 156

            Dedicated Line Requirements (4.1.1.3) 157

            Cost-Effectiveness and Flexibility of Frame Relay (4.1.1.4) 159

        Frame Relay Operation (4.1.2) 160

            Virtual Circuits (4.1.2.1) 160

            Multiple Virtual Circuits (4.1.2.2) 163

            Frame Relay Encapsulation (4.1.2.3) 165

            Frame Relay Topologies (4.1.2.4, 4.1.2.5) 167

            Frame Relay Address Mapping (4.1.2.6) 171

            Local Management Interface (LMI) (4.1.2.7) 174

            LMI Extensions (4.1.2.8) 175

            Using LMI and Inverse ARP to Map Addresses (4.1.2.9) 178

        Advanced Frame Relay Concepts (4.1.3) 180

            Access Rate and Committed Information Rate (4.1.3.1) 180

            Frame Relay Example (4.1.3.2) 181

            Bursting (4.1.3.3) 183

            Frame Relay Flow Control (4.1.3.4) 184

    Configure Frame Relay (4.2) 187

        Configure Basic Frame Relay (4.2.1) 187

            Basic Frame Relay Configuration Commands (4.2.1.1) 187

            Configuring a Static Frame Relay Map (4.2.1.2) 190

            Verify a Static Frame Relay Map (4.2.1.3) 192

        Configure Subinterfaces (4.2.2) 193

            Reachability Issues (4.2.2.1) 193

            Solving Reachability Issues (4.2.2.2) 196

            Configuring Point-to-Point Subinterfaces (4.2.2.3) 199

            Example: Configuring Point-to-Point Subinterfaces (4.2.2.4) 200

    Troubleshoot Connectivity (4.3) 203

        Troubleshoot Frame Relay (4.3.1) 203

            Verifying Frame Relay Operation: Frame Relay Interface (4.3.1.1) 203

            Verifying Frame Relay Operation: LMI Operations (4.3.1.2) 204

            Verifying Frame Relay Operation: PVC Status (4.3.1.3) 205

            Verifying Frame Relay Operation: Inverse ARP (4.3.1.4) 205

            Troubleshooting Frame Relay Operation (4.3.1.5) 207

    Summary (4.4) 209

    Practice 210

        Class Activities 210

        Labs 210

        Packet Tracer Activities 210

    Check Your Understanding Questions 211

Chapter 5: Network Address Translation for IPv4 217

    Objectives 217

    Key Terms 217

    Introduction (5.0.1.1) 218

    NAT Operation (5.1) 219

        NAT Characteristics (5.1.1) 219

            IPv4 Private Address Space (5.1.1.1) 219

            What Is NAT? (5.1.1.2) 220

            NAT Terminology (5.1.1.3) 221

            How NAT Works (5.1.1.5) 224

        Types of NAT (5.1.2) 225

            Static NAT (5.1.2.1) 225

            Dynamic NAT (5.1.2.2) 226

            Port Address Translation (PAT) (5.1.2.3) 227

            Next Available Port (5.1.2.4) 228

            Comparing NAT and PAT (5.1.2.5) 230

    Benefits of NAT (5.1.3) 231

            Benefits of NAT (5.1.3.1) 231

            Disadvantages of NAT (5.1.3.2) 232

    Configuring NAT (5.2) 233

        Configuring Static NAT (5.2.1) 233

            Configuring Static NAT (5.2.1.1) 233

            Analyzing Static NAT (5.2.1.2) 235

            Verifying Static NAT (5.2.1.3) 237

        Configuring Dynamic NAT (5.2.2) 238

            Dynamic NAT Operation (5.2.2.1) 238

            Configuring Dynamic NAT (5.2.2.2) 239

            Analyzing Dynamic NAT (5.2.2.3) 242

            Verifying Dynamic NAT (5.2.2.4) 244

        Configuring Port Address Translation (PAT) (5.2.3) 247

            Configuring PAT: Address Pool (5.2.3.1) 247

            Configuring PAT: Single Address (5.2.3.2) 249

            Analyzing PAT (5.2.3.3) 251

            Verifying PAT (5.2.3.4) 253

        Port Forwarding (5.2.4) 255

            Port Forwarding (5.2.4.1) 255

            SOHO Example (5.2.4.2) 257

            Configuring Port Forwarding with IOS (5.2.4.3) 258

        Configuring NAT and IPv6 (5.2.5) 260

            NAT for IPv6? (5.2.5.1) 260

            IPv6 Unique Local Addresses (5.2.5.2) 262

            NAT for IPv6 (5.2.5.3) 263

    Troubleshooting NAT (5.3) 264

            Troubleshooting NAT: show Commands (5.3.1.1) 264

            Troubleshooting NAT: debug Command (5.3.1.2) 266

            Case Study (5.3.1.3) 268

    Summary (5.4) 271

    Practice 272

        Class Activities 272

        Labs 272

        Packet Tracer Activities 272

    Check Your Understanding Questions 273

Chapter 6: Broadband Solutions 279

    Objectives 279

    Key Terms 279

    Introduction (6.0.1.1) 280

    Teleworking (6.1) 280

        Benefits of Teleworking (6.1.1) 280

            Introducing Teleworking (6.1.1.1) 281

            Employer Benefits of Teleworking (6.1.1.2) 281

            Community and Government Benefits (6.1.1.3) 282

            Individual Benefits of Teleworking (6.1.1.4) 283

            Detriments to Telework (6.1.1.5) 283

        Business Requirements for Teleworker Services (6.1.2) 284

            Teleworker Solution (6.1.2.1) 284

        Teleworker Connectivity Requirements (6.1.2.2) 286

    Comparing Broadband Solutions (6.2) 287

        Cable (6.2.1) 287

            What is a Cable System? (6.2.1.1) 287

            Cable and the Electromagnetic Spectrum (6.2.1.2) 289

            DOCSIS (6.2.1.3) 290

            Cable Components (6.2.1.4) 291

        DSL (6.2.2) 293

            What is DSL? (6.2.2.1) 293

            DSL Connections (6.2.2.2) 294

            Separating Voice and Data in ADSL (6.2.2.3) 295

    Broadband Wireless (6.2.3) 298

            Types of Broadband Wireless Technologies (6.2.3.1, 6.2.3.2) 298

        Selecting Broadband Solutions (6.2.4) 303

            Comparing Broadband Solutions (6.2.4.1) 303

    Configuring xDSL Connectivity (6.3) 304

        PPPoE Overview (6.3.1) 304

            PPPoE Motivation (6.3.1.1) 304

            PPPoE Concepts (6.3.1.2) 306

        Configuring PPPoE (6.3.2) 306

            PPPoE Configuration (6.3.2.1) 307

    Summary (6.4) 309

    Practice 310

        Class Activities 310

        Labs 310

    Check Your Understanding Questions 310

Chapter 7: Securing Site-to-Site Connectivity 313

    Objectives 313

    Key Terms 313

    Introduction (7.0.1.1) 314

    VPNs (7.1) 314

        Fundamentals of VPNs (7.1.1) 314

            Introducing VPNs (7.1.1.1) 315

            Benefits of VPNs (7.1.1.2) 316

        Types of VPNs (7.1.2) 317

            Remote-Access VPNs (7.1.2.2) 318

    Site-to-Site GRE Tunnels (7.2) 319

        Fundamentals of Generic Routing Encapsulation (7.2.1) 319

            Introduction to GRE (7.2.1.1) 319

            Characteristics of GRE (7.2.1.2) 320

            Configuring GRE Tunnels (7.2.2) 321

            GRE Tunnel Configuration (7.2.2.1) 322

            GRE Tunnel Verification (7.2.2.2) 324

    Introducing IPsec (7.3) 326

        Internet Protocol Security (7.3.1) 326

            IPsec (7.3.1.1) 326

            IPsec Security Services (7.3.1.2) 327

        IPsec Framework (7.3.2) 328

            Confidentiality with Encryption (7.3.2.1) 328

            Encryption Algorithms (7.3.2.2) 330

            Diffie-Hellman Key Exchange (7.3.2.3) 332

            Integrity with Hash Algorithms (7.3.2.4) 332

            IPsec Authentication (7.3.2.5) 334

            IPsec Protocol Framework (7.3.2.6) 335

    Remote Access (7.4) 337

        Remote-Access VPN Solutions (7.4.1) 337

            Types of Remote-Access VPNs (7.4.1.1) 337

            Cisco SSL VPN (7.4.1.2) 338

            Cisco SSL VPN Solutions (7.4.1.3) 340

        IPsec Remote-Access VPNs (7.4.2) 341

            IPsec Remote Access (7.4.2.1) 341

            Cisco Easy VPN Server and Remote (7.4.2.2) 342

            Cisco Easy VPN Client (7.4.2.3) 343

            Comparing IPsec and SSL (7.4.2.4) 345

    Summary (7.5) 347

    Practice 348

        Class Activities 348

        Labs 348

        Packet Tracer Activities 348

    Check Your Understanding Questions 348

Chapter 8: Monitoring the Network 351

    Objectives 351

    Key Terms 351

    Introduction (8.0.1.1) 352

    Syslog (8.1) 352

        Syslog Operation (8.1.1) 352

            Introduction to Syslog (8.1.1.1) 352

            Syslog Operation (8.1.1.2) 354

            Syslog Message Format (8.1.1.3) 355

            Service Timestamp (8.1.1.4) 357

        Configuring Syslog (8.1.2) 358

            Syslog Server (8.1.2.1) 358

            Default Logging (8.1.2.2) 359

            Router and Switch Commands for Syslog Clients (8.1.2.3) 360

            Verifying Syslog (8.1.2.4) 362

    SNMP (8.2) 364

        SNMP Operation (8.2.1) 364

            Introduction to SNMP (8.2.1.1) 364

            SNMP Operation (8.2.1.2) 365

            SNMP Agent Traps (8.2.1.3) 366

            SNMP Versions (8.2.1.4) 368

            Community Strings (8.2.1.5) 370

            Management Information Base Object ID (8.2.1.6) 371

        Configuring SNMP (8.2.2) 374

            Steps for Configuring SNMP (8.2.2.1) 374

            Verifying SNMP Configuration (8.2.2.2) 375

            Security Best Practices (8.2.2.3) 378

    NetFlow (8.3) 380

        NetFlow Operation (8.3.1) 380

            Introducing NetFlow (8.3.1.1) 380

            Understanding NetFlow (8.3.1.2) 381

            Network Flows (8.3.1.3) 383

        Configuring NetFlow (8.3.2) 384

            Verifying NetFlow (8.3.2.2) 386

        Examining Traffic Patterns (8.3.3) 390

            Identifying NetFlow Collector Functions (8.3.3.1) 390

            NetFlow Analysis with a NetFlow Collector (8.3.3.2) 392

    Summary (8.4) 397

    Practice 397

        Class Activities 398

        Labs 398

        Packet Tracer Activities 398

    Check Your Understanding Questions 398

Chapter 9: Troubleshooting the Network 401

    Objectives 401

    Key Terms 401

    Introduction (9.0.1.1) 402

    Troubleshooting with a Systematic Approach (9.1) 402

        Network Documentation (9.1.1) 402

            Documenting the Network (9.1.1.1) 403

            Network Topology Diagrams (9.1.1.2) 406

            Network Baseline Performance Level (9.1.1.3) 408

            Establishing a Network Baseline (9.1.1.4) 409

            Measuring Data (9.1.1.5) 412

        Troubleshooting Process (9.1.2) 415

            General Troubleshooting Procedures (9.1.2.1) 415

            Gathering Symptoms (9.1.2.2) 417

            Questioning End Users (9.1.2.3) 418

        Isolating the Issue Using Layered Models (9.1.3) 419

            Using Layered Models for Troubleshooting (9.1.3.1) 419

            Troubleshooting Methods (9.1.3.2, 9.1.3.3) 422

            Guidelines for Selecting a Troubleshooting Method (9.1.3.4) 425

    Network Troubleshooting (9.2) 426

        Troubleshooting Tools (9.2.1) 426

            Software Troubleshooting Tools (9.2.1.1, 9.2.1.2) 426

            Hardware Troubleshooting Tools (9.2.1.3) 431

            Using a Syslog Server for Troubleshooting (9.2.1.4) 435

        Symptoms and Causes of Network Troubleshooting (9.2.2) 437

            Physical Layer Troubleshooting (9.2.2.1) 437

            Data Link Layer Troubleshooting (9.2.2.2) 439

            Network Layer Troubleshooting (9.2.2.3) 441

            Transport Layer Troubleshooting — ACLs (9.2.2.4) 443

            Transport Layer Troubleshooting — NAT for IPv4 (9.2.2.5) 445

            Application Layer Troubleshooting (9.2.2.6) 446

        Troubleshooting IP Connectivity (9.2.3) 448

            Components of Troubleshooting End-to-End Connectivity (9.2.3.1) 448

            End-to-End Connectivity Problem Initiates Troubleshooting (9.2.3.2) 450

            Step 1 - Verify the Physical Layer (9.2.3.3) 452

            Step 2 - Check for Duplex Mismatches (9.2.3.4) 454

            Step 3 - Verify Layer 2 and Layer 3 Addressing on the Local Network (9.2.3.5) 456

            Step 4 - Verify Default Gateway (9.2.3.6) 461

            Step 5 - Verify Correct Path (9.2.3.7) 464

            Step 6 - Verify the Transport Layer (9.2.3.8) 468

            Step 7 - Verify ACLs (9.2.3.9) 469

            Step 8 - Verify DNS (9.2.3.10) 471

    Summary (9.3) 474

    Practice 475

        Class Activities 475

        Packet Tracer Activities 475

    Check Your Understanding Questions 476

Appendix A: Answers to the “Check Your Understanding” Questions 479

Glossary 499

TOC, 9781587133329, 3/25/2014