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Cisco DQOS Exam Certification Guide (DQOS Exam #9E0-601 and QOS Exam #642-641)


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  • Modular Chapter Organization.
    • Breaks topics down into smaller, easy to understand and absorb blocks of information.

  • Simulation Based Questions.
    • Emulates new testing environment and test hands-on networking skills.

  • CD-ROM Testing Engine and Chapter-ending quizzes.
    • Provides students with feedback on areas requiring further study.

  • Hands-on Lab Exercises.
    • Develops student's ability to apply concepts in real-worl setting, improving concept comprehension.

  • Aligned to Cisco Certification exam objectives.
    • Prepares students for exam.

  • Only Cisco Systems authorized materials of its kind.
    • Students gain knowledge from the source of the exams, courses and technology of the CCNA exam.

  • Copyright 2004
  • Dimensions: 7-3/8" x 9-1/8"
  • Pages: 936
  • Edition: 1st
  • Book
  • ISBN-10: 1-58720-058-9
  • ISBN-13: 978-1-58720-058-8

The official self-study test preparation guide for the Cisco DQOS 9E0-601 and QOS 642-641 exams

This official study guide helps you master all the topics on the DQOS exam, including:

  • QoS concepts, tools, and architectures
  • Classification and marking concepts and tools
  • Queuing in Cisco routers and configuration of queuing tools
  • Traffic policing and shaping in Cisco routers
  • Configuration of congestion avoidance tools
  • Configuration of link-efficiency tools
  • Call admission control (CAC) tools for voice and video connections
  • Cisco QoS management tools
  • QoS design processes
  • QoS on LAN switches

The Cisco IP Telephony Support, Design, and Operations Specialist focused certifications validate proficiency in designing, installing, and supporting a multiservice network solution. A solid understanding of quality-of-service (QoS) features and implementation is essential for all of the Cisco IP Telephony focused certifications and is also a core component of the CCIP(tm) certification.

Cisco DQOS Exam Certification Guide is a best-of-breed Cisco(r) exam study guide that focuses specifically on the objectives for the DQOS exam. Senior instructor and best-selling author Wendell Odom and senior Cisco AVVID consultant Michael Cavanaugh share preparation hints and test-taking tips, helping you identify areas of weakness and improve your QoS knowledge. Material is presented in a concise manner, focusing on increasing your understanding and retention of exam topics.

Cisco DQOS Exam Certification Guide presents you with an organized test preparation routine through the use of proven series elements and techniques. "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 Foundation Summary tables 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 that help you prepare for the QoS component of either the IP Telephony or CCIP certifications. The assessment engine also tracks your performance and provides feedback on a module-by-module 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 will enable you to succeed on the exam the first time.

Cisco DQOS Exam Certification Guide is part of a recommended study program from Cisco Systems(r) that includes simulation and hands-on training from authorized Cisco Learning Partners and self-study products from Cisco Press. To find out more about instructor-led, e-learning, and hands-on instruction offered by authorized Cisco Learning Partners worldwide, please visit

Companion CD-ROM
The companion CD-ROM contains a test bank with over 200 practice questions and an electronic version of the text.

This volume is part of the Exam Certification Guide Series from Cisco Press(r). 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.


Download - 28 KB - Test Tips for the New QOS Exam

Online Sample Chapter

Classification and Marking for Cisco DQOS and QOS Exams

Downloadable Sample Chapter

Download - 925 KB -- Chapter 3: Classification and Marking

Table of Contents



1. QoS Overview.

"Do I Know This Already?" Quiz.

QoS: Tuning Bandwidth, Delay, Jitter, and Loss Questions. Traffic Characteristics of Voice, Video, and Data Questions.

Foundation Topics. QoS: Tuning Bandwidth, Delay, Jitter, and Loss.

Bandwidth. Delay. Jitter. Loss. Summary: QoS Characteristics: Bandwidth, Delay, Jitter, and Loss.

Traffic Characteristics of Voice, Video, and Data.

Voice Traffic Characteristics. Video Traffic Characteristics. Data Traffic Characteristics.

Foundation Summary. Q&A.

2. QoS Tools and Architectures.

"Do I Know This Already?" Quiz.

QoS Tools Questions. Differentiated Services Questions. Integrated Services Questions.

Foundation Topics. Introduction to IOS QoS Tools.

Classification and Marking. Queuing. Shaping and Policing. Congestion Avoidance. Link Efficiency. Call Admission Control and RSVP. Management Tools. Summary.

The Good-Old Common Sense QoS Model.

GOCS Flow-Based QoS. GOCS Class-Based QoS.

The Differentiated Services QoS Model.

DiffServ Specifications and Terminology. DiffServ Per-Hop Behaviors. DiffServ Classifiers and Traffic Conditioners.

The Integrated Services QoS Model. Foundation Summary. Q&A.

3. Classification and Marking.

"Do I Know This Already?" Quiz Questions.

Classification and Marking Concepts Questions. CAR, PBR, and CB Marking Questions.

Foundation Topics. Classification and Marking Concepts.

Classification. Marking. Classification and Marking Design Choices.

Classification and Marking Tools.

Class-Based Marking (CB Marking). Committed Access Rate (CAR). Policy-Based Routing (PBR). VoIP Dial Peer. Summary of Classification and Marking QoS Features.

Foundation Summary. Q&A.

4. Congestion Management.

"Do I Know This Already?" Quiz.

Queuing Concepts Questions. WFQ and IP RTP Priority Questions. CBWFQ and LLQ Questions. Comparing Queuing Options Questions.

Foundation Topics. Queuing Concepts.

Output Queues, TX Rings, and TX Queues. Queuing on Interfaces Versus Subinterfaces and Virtual Circuits (VCs). Summary of Queuing Concepts.

Queuing Tools.

FIFO Queuing. Priority Queuing. Custom Queuing. Weighted Fair Queuing (WFQ). Class-Based WFQ (CBWFQ). Low Latency Queuing (LLQ). IP RTP Priority. Summary of Queuing Tool Features.

Foundation Summary. Q&A. Conceptual Questions. Priority Queuing and Custom Queuing. WFQ. CBWFQ, LLQ, IP RTP Priority. Comparing Queuing Tool Options.

5. Traffic Policing and Shaping.

"Do I Know This Already?" Quiz.

Shaping and Policing Concepts Questions. Policing with CAR and CB Policer Questions. Shaping with FRTS, GTS, DTS, and CB Shaping.

Foundation Topics. Traffic-Policing and Traffic-Shaping Concepts.

When and Where to Use Shaping and Policing. How Shaping Works. How Policing Works.

Traffic-Shaping Tools.

Generic Traffic-Shaping Configuration. Class-Based Shaping Configuration. Distributed Traffic Shaping (DTS) Configuration. Frame Relay Traffic Shaping (FRTS) Configuration.

Traffic-Policing Tools.

Class-Based Policing Configuration. Committed Access Rate (CAR) Configuration.

Foundation Summary. Q&A. Shaping and Policing Concepts. Traffic Shaping. Traffic-Policing Tools.

6. Congestion Avoidance Through Drop Policies.

"Do I Know This Already?" Quiz.

Congestion-Avoidance Concepts and RED Questions. WRED Questions. FRED Questions.

Foundation Topics. Congestion-Avoidance Concepts and Random Early Detection (RED).

TCP and UDP Reactions to Packet Loss. Tail Drop, Global Synchronization, and TCP Starvation. Random Early Detection (RED).

Weighted RED (WRED).

How WRED Weights Packets. WRED and Queuing. WRED Configuration. WRED Summary.

Flow-Based WRED (FRED).

FRED Configuration.

Foundation Summary. Q&A. Congestion-Avoidance Concepts and Random Early Detection (RED). Weighted RED (WRED). Flow-Based WRED (FRED).

7. Link-Efficiency Tools.

"Do I Know This Already?" Quiz.

Compression Questions. Link Fragmentation and Interleave Questions.

Foundation Topics. Payload and Header Compression.

Payload Compression. Header Compression. Payload Compression Configuration. TCP and RTP Header Compression Configuration.

Link Fragmentation and Interleaving.

Multilink PPP LFI. Frame Relay LFI Using FRF.12. Multilink PPP Interleaving Configuration. Frame Relay Fragmentation Configuration.

Foundation Summary. Q&A. Compression Tools. LFI Tools.

8. Call Admission Controland QoS Signaling.

"Do I Know This Already?" Quiz. Foundation Topics. Call Admission Control Overview.

Call Rerouting Alternatives. Bandwidth Engineering. CAC Mechanisms. CAC Mechanism Evaluation Criteria.

Local Voice CAC.

Physical DS0 Limitation. Max-Connections. Voice over Frame Relay-Voice Bandwidth. Trunk Conditioning. Local Voice Busyout.

Measurement-Based Voice CAC.

Service Assurance Agents. Advanced Voice Busyout. PSTN Fallback.

Resource-Based CAC.

Resource Availability Indication. Cisco CallManager Resource-Based CAC. Gatekeeper Zone Bandwidth. Integrated Services / Resource Reservation Protocol.

Foundation Summary. Q&A. Call Admission Control Concepts. Local-Based CAC. Measurement-Based CAC. Resources-Based CAC.

9. Management Tools and QoS Design.

"Do I Know This Already?" Quiz.

QoS Management Tools Questions. QoS Design Questions.

Foundation Topics. QoS Management Tools.

QoS Device Manager. QoS Policy Manager. Service Assurance Agent. Internetwork Performance Monitor. Service Management Solution. QoS Management Tool Summary.

QoS Design for the Cisco QoS Exams.

Four-Step QoS Design Process. QoS Design Guidelines for Voice and Video.

Foundation Summary. Q&A. QoS Management. QoS Design.

10. LAN QoS.

"Do I Know This Already?" Quiz. Foundation Topics. The Need for QoS on the LAN.

Buffer Overflow (Overrun). Marking and Classification. Layer 3-to-Layer 2 Classification Mapping. Layer 2 Queues. Drop Thresholds. Trust Boundries.

Cisco Catalyst Switch QoS Features.

Catalyst 6500 QoS Features. QoS Flow on the Catalyst 6500. Catalyst 6500 QoS Summary. Cisco Catalyst 4500/4000 QoS Features. Cisco Catalyst 3550 QoS Features. Cisco Catalyst 3524 QoS Features.

QoS Configurations on Catalyst Switches.

Configuration of a Catalyst Switch Using Catalyst OS. Configuration of a Catalyst Switch Using IOS.

Foundation Summary. Q&A. LAN QoS Concepts. Catalyst 6500 Series of Switches. Catalyst 4500/4000 Series of Switches. Catalyst 3550/3524 Series of Switches.

Appendix A. Answers to the "Do I Know This Already?" Quizzes and Q&A Sections.

Appendix B. Topics on the CCIP QoS Exam.



Download - 135 KB -- Index


Errata -- 24 KB

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