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CCNP ONT Official Exam Certification Guide


  • Sorry, this book is no longer in print.
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  • Description
  • Sample Content
  • Updates
  • Copyright 2007
  • Edition: 1st
  • Book
  • ISBN-10: 1-58720-176-3
  • ISBN-13: 978-1-58720-176-9

  • Master all 642-845 exam topics with the official study guide
  • Assess your knowledge with chapter-opening quizzes
  • Review key concepts with foundation summaries
  • Practice with hundreds of exam questions on the CD-ROM

Amir Ranjbar, CCIE® No. 8669

CCNP ONT Official Exam Certification Guide is a best of breed Cisco® exam study guide that focuses specifically on the objectives for the Optimizing Converged Cisco Networks exam (642-845 ONT). Successfully passing the ONT 642-845 exam certifies that you have the knowledge and skills necessary to optimize and apply effective QoS techniques for converged networks.

CCNP ONT Official Exam Certification Guide follows a logical organization of the CCNP® ONT exam objectives. Material is presented in a concise manner, focusing on increasing your retention and recall of exam topics. You can organize your exam preparation through the use of the consistent features in these chapters. “Do I Know This Already?” quizzes open each chapter and allow you to decide how much time you need to spend on each section. Exam topic lists and concise Foundation Summary information make referencing easy and give you a quick refresher whenever you need it. Challenging chapter-ending review questions help you assess your knowledge and reinforce key concepts.

The companion CD-ROM contains a powerful testing engine that allows you to focus on individual topic areas or take complete, timed exams. The assessment engine also tracks your performance and provides feedback on a topic-by-topic basis, presenting question-by-question remediation to the text. Well regarded for its level of detail, assessment features, and challenging review questions and exercises, this book helps you master the concepts and techniques that can enable you to succeed on the exam the first time.

Amir Ranjbar, CCIE® No. 8669, is a certified Cisco instructor and an internetworking consultant. He conducts Cisco official courses such as BCMSN, BSCI, ONT, CVOICE, BGP, and MPLS for Global Knowledge, the largest Cisco training partner. Amir has a bachelor’s degree in computing and information science and a master’s degree in knowledge-based systems from the University of Guelph in Ontario, Canada.

The official study guide helps you master all the topics on the CCNP ONT exam, including

  • Implementing a voice-over-IP (VoIP) network
  • Implementing QoS on converged networks
  • Specific IP QoS mechanisms for implementing the DiffServ QoS model
  • AutoQoS
  • Wireless security
  • Basic wireless management

Companion CD-ROM

The CD-ROM contains an electronic copy of the book and more than 200 practice questions for the ONT exam, which are all available in study mode, test mode, and flash card format.

This volume is part of the Exam Certification Guide Series from Cisco Press®. Books in this series provide officially developed exam preparation materials that offer assessment, review, and practice to help Cisco Career Certification candidates identify weaknesses, concentrate their study efforts, and enhance their confidence as exam day nears.

Category: Cisco Certification

Covers: ONT Exam 642-845

Online Sample Chapter

Preparing for the CCNP ONT Exam: IP Quality of Service

Downloadable Sample Chapter

Download - 1.42 MB -- Chapter 2: IP Quality of Service

Table of Contents

Part I Voice over IP 3

Chapter 1 Cisco VoIP Implementations 5

“Do I Know This Already?” Quiz 5

Foundation Topics 10

Introduction to VoIP Networks 10

    Benefits of Packet Telephony Networks 10

    Packet Telephony Components 11

    Analog Interfaces 13

    Digital Interfaces 14

    Stages of a Phone Call 15

    Distributed Versus Centralized Call Control 16

Digitizing and Packetizing Voice 19

    Basic Voice Encoding: Converting Analog to Digital 19

    Basic Voice Encoding: Converting Digital to Analog 20

    The Nyquist Theorem 21

    Quantization 22

    Compression Bandwidth Requirements and Their Comparative Qualities 24

    Digital Signal Processors 25

Encapsulating Voice Packets 27

    End-to-End Delivery of Voice 27

    Protocols Used in Voice Encapsulation 30

    Reducing Header Overhead 32

Bandwidth Calculation 34

    Impact of Voice Samples and Packet Size on Bandwidth 34

    Data Link Overhead 37

    Security and Tunneling Overhead 37

    Calculating the Total Bandwidth for a VoIP Call 39

    Effects of VAD on Bandwidth 41

Implementing VoIP Support in an Enterprise Network 42

    Enterprise Voice Implementations 42

    Voice Gateway Functions on a Cisco Router 44

    Cisco Unified CallManager Functions 45

    Enterprise IP Telephony Deployment Models 46

    Single-Site Model 46

    Multisite with Centralized Call Processing Model 46

    Multisite with Distributed Call Processing Model 47

    Clustering over WAN Model 48

    Identifying Voice Commands in IOS Configurations 48

    Call Admission Control (CAC) 49

Part II Quality of Service 55

Chapter 2 IP Quality of Service 57

“Do I Know This Already?” Quiz 57

Foundation Topics 62

Introduction to QoS 62

    Converged Network Issues Related to QoS 62

    Available Bandwidth 63

    End-to-End Delay 64

    Delay Variation 65

    Packet Loss 66

    Definition of QoS and the Three Steps to Implementing It 68

    Implementing QoS 69

    Identifying and Comparing QoS Models 72

    Best-Effort Model 72

    Integrated Services Model 73

    Differentiated Services Model 74

    QoS Implementation Methods 76

    Legacy Command-Line Interface (CLI) 76

    Modular QoS Command-Line Interface (MQC) 76

    AutoQoS 79

    Router and Security Device Manager (SDM) QoS Wizard 81

Foundation Summary 89

Q&A 91

Chapter 3 Classification, Marking, and NBAR 93

“Do I Know This Already?” Quiz 93

Foundation Topics 97

Classification and Marking 97

    Layer 2 QoS: CoS on 802.1Q/P Ethernet Frame 98

    Layer 2 QoS: DE and CLP on Frame Relay and ATM (Cells) 99

    Layer 2 1/2 QoS: MPLS EXP Field 100

The DiffServ Model, Differentiated Services Code Point (DSCP), and Per-Hop Behavior

(PHB) 100

    IP Precedence and DSCP 102

QoS Service Class 106

Trust Boundaries 108

Network Based Application Recognition (NBAR) 110

Cisco IOS Commands to Configure NBAR 112

Foundation Summary 118

Q&A 119

Chapter 4 Congestion Management and Queuing 123

“Do I Know This Already?” Quiz 123

Foundation Topics 127

Introduction to Congestion Management and Queuing 127

First-In-First-Out, Priority Queuing, Round-Robin, and Weighted Round-Robin Queuing 130

Weighted Fair Queuing 132

    WFQ Classification and Scheduling 133

    WFQ Insertion and Drop Policy 135

    Benefits and Drawbacks of WFQ 135

    Configuring and Monitoring WFQ 135

Class-Based Weighted Fair Queuing 138

    Classification, Scheduling, and Bandwidth Guarantee 139

    Benefits and Drawbacks of CBWFQ 140

    Configuring and Monitoring CBWFQ 141

Low-Latency Queuing 142

    Benefits of LLQ 144

    Configuring and Monitoring LLQ 144

Foundation Summary 146

Q&A 147

Chapter 5 Congestion Avoidance, Policing, Shaping, and Link

Efficiency Mechanisms 149

“Do I Know This Already?” Quiz 149

Foundation Topics 153

Congestion Avoidance 153

    Tail Drop and Its Limitations 153

    Random Early Detection 154

    Weighted Random Early Detection 156

    Class-Based Weighted Random Early Detection 158

    Configuring CBWRED 158

Traffic Shaping and Policing 163

    Measuring Traffic Rates 165

    Cisco IOS Policing and Shaping Mechanisms 167

Link Efficiency Mechanisms 167

    Layer 2 Payload Compression 168

    Header Compression 169

    Link Fragmentation and Interleaving 171

    Applying Link Efficiency Mechanisms 171

Foundation Summary 172

Q&A 175

Chapter 6 Implementing QoS Pre-Classify and Deploying End-to-End QoS 177

“Do I Know This Already?” Quiz 177

Foundation Topics 180

Implementing QoS Pre-Classify 180

    Virtual Private Networks (VPN) 180

    QoS Pre-Classify Applications 181

    QoS Pre-Classification Deployment Options 183

Deploying End-to-End QoS 185

    QoS Service Level Agreements (SLAs) 186

    Enterprise Campus QoS Implementations 188

    WAN Edge QoS Implementations 190

    Control Plane Policing (CoPP) 192

Foundation Summary 194

Q&A 198

Chapter 7 Implementing AutoQoS 201

“Do I Know This Already?” Quiz 201

Foundation Topics 205

Introducing AutoQoS 205

Implementing and Verifying AutoQoS 207

    Two-Step Deployment of AutoQoS Enterprise on Routers 209

    Deploying AutoQoS VoIP on IOS-Based Catalyst Switches 210

    Verifying AutoQoS on Cisco Routers and IOS-Based Catalyst Switches 212

    AutoQoS Shortcomings and Remedies 215

    Automation with Cisco AutoQoS 215

    Common AutoQoS Problems 218

    Interpreting and Modifying AutoQoS Configurations 219

Foundation Summary 222

Q&A 227

Part III Wireless LAN 229

Chapter 8 Wireless LAN QoS Implementation 231

“Do I Know This Already?” Quiz 231

Foundation Topics 235

The Need for Wireless LAN QoS 235

    WLAN QoS Description 237

    Split MAC Architecture and Light Weight Access Point 238

Current Wireless LAN QoS Implementation 239

Configuring Wireless LAN QoS 243

Foundation Summary 247

Q&A 252

Chapter 9 Introducing 802.1x and Configuring Encryption and Authentication

on Lightweight Access Points 255

“Do I Know This Already?” Quiz 255

Foundation Topics 258

Overview of WLAN Security 258

    WLAN Security Issues 258

    Evolution of WLAN Security Solutions 259

802.1x and EAP Authentication Protocols 260

    EAP Authentication Protocols 262

    Cisco LEAP 262

    EAP-FAST 264

    EAP-TLS 266

    PEAP 267

    WPA, 802.11i, and WPA2 269

Configuring Encryption and Authentication on Lightweight Access Points 272

    Open Authentication 272

    Static WEP Authentication 273

    WPA Preshared Key 274

    Web Authentication 276

    802.1x Authentication 278

Foundation Summary 281

Q&A 285

Chapter 10 WLAN Management 287

“Do I Know This Already?” Quiz 287

Foundation Topics 291

The Need for WLAN Management 291

    Cisco Unified Wireless Networks 291

    Cisco WLAN Implementation 292

    WLAN Components 294

CiscoWorks Wireless LAN Solution Engine 295

    WLSE Software Features 295

    WLSE Key Benefits 296

CiscoWorks WLSE and WLSE Express 296

    Simplified WLSE Express Setup 297

    WLSE Configuration Templates 298

    WLSE IDS Features 298

    WLSE Summary 298

Cisco Wireless Control System 299

    WCS Location Tracking Options 300

    WCS Base Software Features 300

    WCS Location Software Features 301

    WCS Location + 2700 Series Wireless Location Appliance Features 301

    WCS System Features 301

    Cisco WCS User Interface 302

    Cisco WCS System Requirements 302

    WCS Summary Pages 303

    Wireless Location Appliance 304

    Wireless Location Appliance Architecture 305

    Wireless Location Appliance Applications 305

    WCS Configuration Examples 306

    WCS Login Steps 306

    Changing the Root Password 306

    Adding a Wireless LAN Controller 307

    Configuring Access Points 308

    WCS Map 309

    Adding a Campus Map 309

    Adding a New Building 310

    Rogue Access Point Detection 312

    Rogue Access Point Alarms 312

    Rogue Access Point Location 313

Foundation Summary 314

Q&A 317

Part IV Appendix 319

Appendix A Answers to the “Do I Know This Already?” Quizzes and Q&A Sections 321


Download - 680 KB -- Index

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