CWDP Certified Wireless Design Professional Official Study Guide E-Book

Shawn M. Jackman

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 1470

Veröffentlichungsjahr: 2011

Beschreibung

The official study guide for the Certified Wireless Design Professional (CWDP) exam from CWNP! This official guide is what you need to prepare for the vendor-neutral CWDP exam (PW0-250), which tests an IT professional's ability to design, plan, and troubleshoot a wireless network. Administered by CWNP, the industry leader for enterprise Wi-Fi training and certification, the CWDP exam is for those operating in large WLAN deployments. This practical guide not only covers all exam objectives, it also gives you practical information on designing for complex environments such as businesses, hospitals, educational facilities, and in outdoor spaces. * Covers all exam objectives for the Certified Wireless Design Professional (CWDP) exam, exam PW0-250 * Covers planning, developing a WLAN design strategy and RF, conducting advanced site surveying, developing 802.11 security, and troubleshooting * Companion CD includes two practice exams and over 100 electronic flashcards * Sybex is the official publisher for Certified Wireless Network Professional, Inc., the certifying vendor for the CWAP program If you want to prepare for CWNP certification, a Sybex Study Guide is what you need! Note: CD-ROM materials for eBook purchases can be downloaded from href="http://www.cwnp.com/sybex.%20To%20%201Cbooksupport.wiley.com">http://booksupport.wiley.com.

Leseprobe

Contents

Foreword

Introduction

Assessment Test

Chapter 1: Gathering and Analyzing Requirements

Preparation and Planning

Meeting the Customer

Gathering the Requirements

Using a Customer’s Existing Assets to Save Time and Money

Understanding the Deployment Environment

Constraints

Creating the Customer Requirements Document

Statement of Work

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Chapter 2: Designing for Client Devices and Applications

General Client Design Factors

Common Client Device Form Factors

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Chapter 3: Designing for Applications

Understanding WLAN Applications

Guest Access

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Chapter 4: Industry-Specific Design Considerations

Healthcare

Retail

Education

Other Verticals

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Chapter 5: Vendor and WLAN Architecture Selection

Consumer vs. Enterprise Equipment

Management, Control, and Data Planes

Architecture

Additional Vendor Selection Considerations

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Chapter 6: RF Communication Principles

Understanding Basics of RF

Radio Propagation

Modulation

Noise

Units of Measure

Communications Link

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Chapter 7: RF Hardware and 802.11n

RF Cables and Connectors

Filters

Antennas

802.11n

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Chapter 8: Site Survey Preparation

Primary Events

Administrative Items

Environment

Understanding the Wired Network

Survey Equipment

Point-to-Point Links

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Chapter 9: Site Survey RF Design

RF Survey Overview

Spectrum Analysis

Survey Types

Dealing with Multiple Floors

Utilizing Infrastructure Links

Handling Critical Findings

Designing for Dual Spectrums

Survey Client Considerations

Frequency Band–Specific Considerations

PHY Rate Support

Updating an Existing Design

Interpreting Survey Results

MCA vs. SCA

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Chapter 10: MAC Layer Design

Understanding Quality of Service

Protection Modes

Power Management

Roaming and Mobility

WLAN Configuration

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Chapter 11: Basic WLAN Security Design

A General Overview of WLAN Security

Basic WLAN Security

WPA-Personal and WPA2-Personal

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Chapter 12: Advanced Enterprise WLAN Security Design

WPA-Enterprise and WPA2-Enterprise

AAA

User Databases

Extensible Authentication Protocol

PKI and Certificates

Segmentation and Filtering

Captive Portals

Endpoint Security

Virtual Private Networking

WIDS/WIPS

Fast Secure Roaming

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Chapter 13: Documentation and Finalizing the Design Solution

Design Documentation

High-Level Design

Low-Level Design

Operational and Maintenance Plan

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Chapter 14: Post-Installation Validation

Post-Installation RF Assessment

Interference Mitigation

Design Validation

Frame and Channel Analysis

Roaming Analysis

Load and Performance Testing

Application Testing

Failover and Redundancy Testing

Network Approval

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Chapter 15: Design Troubleshooting

Troubleshooting Steps

Spectrum Analysis

Security Model Analysis and Troubleshooting 802.1X Authentication

Quality of Service Analysis

Network Analysis

Pesky Clients

Common Troubleshooting Mistakes: What Not to Do

Summary

Exam Essentials

Review Questions

Answers to Review Questions

Appendix: About the Companion CD

Glossary

Index

Wiley Publishing, Inc. End-User License Agreement

The Best CWDP Book/CD Package on the Market!

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CWDP® Certified Wireless Design Professional

Acquisitions Editor: Jeff Kellum

Development Editor: Denise Santoro Lincoln

Technical Editors: Jennifer Huber; Jerome Henry

Production Editor: Dassi Zeidel

Copy Editor: Liz Welch

Editorial Manager: Pete Gaughan

Production Manager: Tim Tate

Vice President and Executive Group Publisher: Richard Swadley

Vice President and Publisher: Neil Edde

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Book Designers: Judy Fung and Bill Gibson

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Indexer: Ted Laux

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Cover Designer: Ryan Sneed

Copyright © 2011 by Wiley Publishing, Inc., Indianapolis, Indiana

Published simultaneously in Canada

ISBN: 978-0-470-76904-1

ISBN: 978-1-118-04159-8 (ebk.)

ISBN: 978-1-118-04161-1 (ebk.)

ISBN: 978-1-118-04160-4 (ebk.)

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Library of Congress Cataloging-in-Publication Data

CWDP : certified wireless design professional official study / Shawn M. Jackman . . . [et al.]. —1st ed.

p. cm.

ISBN 978-0-470-76904-1 (pbk.)

1. Wireless LANs—Design and construction—Examinations—Study guides. 2. Telecommunications engineers—Certification. I. Jackman, Shawn M., 1974- II. Title: Certified wireless design professional official study guide.

TK5105.78.C94 2011

621.384076—dc22

2010054032

TRADEMARKS: Wiley, the Wiley logo, and the Sybex logo are trademarks or registered trademarks of John Wiley & Sons, Inc. and/or its affiliates, in the United States and other countries, and may not be used without written permission. CWDP is a trademark of CWNP, Inc. All other trademarks are the property of their respective owners. Wiley Publishing, Inc., is not associated with any product or vendor mentioned in this book.

Dear Reader,

Thank you for choosing CWDP: Certified Wireless Design Professional Official Study Guide. This book is part of a family of premium-quality Sybex books, all of which are written by outstanding authors who combine practical experience with a gift for teaching.

Sybex was founded in 1976. More than 30 years later, we’re still committed to producing consistently exceptional books. With each of our titles, we’re working hard to set a new standard for the industry. From the paper we print on, to the authors we work with, our goal is to bring you the best books available.

I hope you see all that reflected in these pages. I’d be very interested to hear your comments and get your feedback on how we’re doing. Feel free to let me know what you think about this or any other Sybex book by sending me an email at [email protected]. If you think you’ve found a technical error in this book, please visit http://sybex.custhelp.com. Customer feedback is critical to our efforts at Sybex.

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We dedicate this book to our families and the continued support that has helped to make this book possible.

Acknowledgments

Shawn Jackman would like to thank his wife, Joy, and his children, Summer, Pierce, and Julia, for the years of unwavering love and support.

Marcus Burton would like to thank his beautiful God, his beautiful wife, and his beautiful kids, Noah and Amalia. Lindsey, I love you today!

Marcus would also like to give an honorable mention to his significantly less beautiful brothers in arms, Devin, Josiah, and the Pudloafs.

Matt Swartz would like to thank his wife, Christie, and children, Lauren and Kyla, for their constant love and support.

Tom Head would like to thank his wife, Meridith, and his children, Laura and Ethan, for their loving support during the writing of this book.

We would all like to thank the following individuals for their support and contributions during the entire process:

We must first thank Sybex Acquisitions Editor Jeff Kellum. Jeff is an extremely patient and understanding editor who occasionally sends a nasty email message, especially when our day jobs take us away from writing for too long. We would also like to thank our development editor, Denise Lincoln. We also need to send special thanks to our editorial manager Pete Gaughan and our production editor Dassi Zeidel, and Liz Welch, our copyeditor. We also want to thank Jennifer Huber and Jerome Henry, our technical editors.

In addition, we thank Kevin Sandlin and Marcus Burton with the CWNP program (www.cwnp.com). You should be proud of the international renowned wireless certification program that you and your team have developed. It has been a pleasure working with all of you over the years.

A special thank you goes to Young Kim for his contribution to Chapter 15. Young’s expertise is deep and wide in both networking and wireless, and his many years of experience with troubleshooting wireless networks is a valuable contribution for all readers.

Shawn would also like to thank the following co-workers and professional colleagues who contributed to this book and his career: Devin Akin, Nico Arcino, Marcus Burton, David Coleman, Ken Fisch, Tom Head, Jon Krabbenschmidt, Charlie Nowak, Zack Ryan, Adam Schembs, George Stefanick, and Matt Swartz.

Tom would also like to thank Elena Bogorad for assistance with proofreading.

Matt would also like to thank his manager at Cisco Systems, Jon Leary, for consistently encouraging him to meet new challenges that have fed his thirst for unsolved problems and driven his technical and personal development.

We would also like to thank the following individuals and companies for their support and contributions to the book:

Aerohive Networks (www.aerohive.com)—Devin Akin, Adam Conway

AeroScout (www.aeroscout.com)—Gabi Daniely

AirMagnet (www.airmagnet.com)—Dilip Advani, Bruce Hubbert

AirTight (www.airtightnetworks.com)—Gopinath KN

Aruba Networks (www.arubanetworks.com)—Andy Logan, Chris Leach

Cisco Systems (www.cisco.com)—Chris Allen, Brian Cox, Jim Florwick, John Helm, Young Kim, Sudheer Matta, Fred Niehaus, Sean Simmons

InfoLogix (www.infologix.com)—Katrina McSweeney

Meraki (www.meraki.com)—John Bicket

Meru Networks (www.merunetworks.com)—Joe Epstein

Phoenix Antennas (www.phoenixantennas.com)—Stephen Tilston, David Tilston

Ruckus Wireless (www.ruckuswireless.com)—GT Hill

SunWize Technologies (www.sunwize.com)—Charlie Bachman, Laurie DuBois

TerraWave (www.terrawave.com)—Carter Burke, Felicia Carreon

VeriWave (www.veriwave.com)—Eran Karoly

Vocera (www.vocera.com)—Chris O’Donnell, Brian Sturges

WildPackets (www.wildpackets.com)—Stephanie Temples

Xirrus (www.xirrus.com)—Violet Smith, Bruce Miller

About the Authors

Shawn Jackman designs and establishes new product offerings and sets Wi-Fi direction for one of the United States’ largest hospital systems, Kaiser Permanente. Shawn coauthored the CWSP Certified Wireless Security Professional Official Study Guide: Exam PW0-204 (Sybex, 2010). He has traveled the United States and internationally, designing wired and wireless networks, from concept to completion, for healthcare, warehouse, hospitality, education, metro/municipal, government, franchise, and retail environments. Shawn is a member of the CWNE Roundtable, a group of individuals who work with the CWNP Program to provide direction for the CWNE exam and certification. He lives in the San Francisco Bay Area with his wife, Joy, and their three children, Summer, Pierce, and Julia. Shawn is CWNE #54, and he can be reached via email at [email protected].

Marcus Burton is the Director of Product Development and primary content developer at CWNP. Marcus has authored or co-authored numerous WLAN exams (CWTS, CWNA, CWSP, CWAP, and CWDP), course guides, whitepapers, and articles. In addition, he has served as technical editor for numerous whitepapers as well as the CWTS: Certified Wireless Technology Specialist Official Study Guide (Sybex, 2009) and the CWSP Certified Wireless Security Professional Official Study Guide (Sybex, 2010). At CWNP, Marcus actively participates with many WLAN vendors in product engineering, testing, and design; he also has in-depth experience with a comprehensive range of WLAN technologies and vendor products. Marcus is CWNE #78.

Matt Swartz is a Technical Leader within Cisco’s Advanced Services Wireless Practice. He delivers scalable designs that enable mobility solutions across many verticals for Cisco’s largest customers. Matt’s most recent focus is on high-density wireless as he drives new technology to expand capacity in these environments. Prior to joining Cisco in 2003, Matt held network engineering positions with a number of service providers and enterprises. He is CCIE #13232 (Routing/Switching & Wireless) and CWNE #57. He also holds a BS degree from Old Dominion University, and is a member of the CWNE Roundtable. Matt can be reached at [email protected].

Thomas Head has been an engineer and manager in the wireless industry for over 20 years. Tom graduated from Rensselaer Polytechnic Institute with a degree in physics. He was an engineer, then manager, of radio design at Lockheed Martin’s spacecraft division. He was also manager of radio programs for Lucent Technologies’ third-generation cellular base station. At Flarion Technologies, Tom was responsible for RF and network testing of Flarion’s innovative Flash-OFDM wireless system. He formed his own company, Aereo Networks, in 2006, which provided wireless test services and software for the US Army, Army Reserves, and major healthcare systems. He can be reached at [email protected].

Foreword

So you want to design an enterprise wireless network? “I can’t connect to the Wi-Fi!” is what you’re going to hear if you don’t get your Wi-Fi right. How do you permanently remove this wonderful end user complaint from your WLAN? It starts with proper design.

I actually considered starting and ending this foreword to the CWDP: Certified Wireless Design Professional Official Study Guide with just the above sentiment. That sums it up, but there is much more to it. Today’s end user expects the wireless network to just work, period. When it doesn’t, customers leave, employees complain, managers scream, and your network is always to blame . . . even when it isn’t.

A few years ago, before Polycom bought them, SpectraLink ran into quite a few of these complaints, only the complaints were “These phones don’t work!” and it really was the network. What did SpectraLink do? They created a services team to design and build their customers’ WLANs properly, so that the SpectraLink phones running on those WLANs would work. It wasn’t the phones. It was the network. The network was not properly designed to support Wi-Fi phones. That was five years ago. Imagine what the network has to support today, thanks to Mr. Steve Jobs!

Whether you’re designing for a coffee shop hotspot or the Super Bowl, your design before the network is implemented will determine hero or goat status. The fun part is, much like security, it gets noticed only when it doesn’t work. If everything works flawlessly, you’ve done your job. When you hear that soulful end user scream—“Mine’s broken!”—then you know you’ve missed the mark.

So how do you design for something you can’t see? RF is a strange animal indeed, often referred to as black magic, or smoke and mirrors, so you must know RF cold. That includes the RF math, behavior, and characteristics, in addition to the building(s) for which you are designing the network. That’s right: you have to know building materials! RF acts differently around cement, metal, drywall, plaster, wood, trees, fences, and, yes, people. That’s part of the reason we require a CWNA before you can be a CWDP. You have to know RF, and you have to know RF really well before you can claim to be a WLAN designer.

And, oh, wouldn’t it be nice if every new WLAN was a sweet new greenfield implementation? Sorry, not going to happen. You will most likely be replacing an old 802.11b or 802.11g WLAN with an 802.11n system. And wouldn’t it be nice if it were just rip and replace? Ha! Life should be so easy! If your manager or your customer suggests rip and replace, you’d do well to suggest that they find someone else to do this job. That should get someone’s attention. Then it’s your job to explain, for example, how differently an 802.11g network and an 802.11n network behave, not only in that particular environment, but in any environment.

With a/b/g, multipath and interference were the bane of your existence. Now, multipath is good for 802.11n Wi-Fi. That means a complete change in the way you design the WLAN for any environment.

Ah, but we don’t design only for the environment, do we? No, no, we don’t. We must design for the specific applications, and the type(s) of and number of devices that will utilize the WLAN, and the specific industry, and the number of end users . . . the list goes on and on. And then there’s VoWiFi and video. How many people have you seen watching (fill in the blank) on YouTube on the wireless LAN? Your WLAN has to support that kind of bandwidth, lest you hear the cry of the end user: “Mine’s broken!”

Reliable enterprise Wi-Fi starts with the design of the wireless network. So where do you start to end up with a great design? You guessed it: your old friend the RF site survey. Missed it, didn’t you? What’s wrong? Haven’t climbed enough towers, scaled enough ceilings, pushed enough carts, dropped enough handhelds, or walked enough miles lately? It’s time to go back to where you started, and improve your game not just a little but a lot. When you did your first 50 RF site surveys, were you thinking about the design of the network, or were you thinking about getting the survey done as quickly and with as little pain as possible?

Now return to the RF site survey with the—no, with your—network design in mind. This time, you’re doing the survey for the purpose of designing a reliable, scalable, secure, mission-critical enterprise wireless LAN. It’s not just Internet access anymore; it is the new access layer technology for the 21st century.

You want to design my wireless network? Start with this book, and see where it takes you.

Kevin Sandlin

Co-Founder and CEO

CWNP, Inc.

Introduction

The content of this book is focused on the real world of wireless design. While this book provides all of the necessary information to pass the CWDP exam, the content is primarily focused on providing tangible value to immediately expand your wireless expertise. The knowledge you will obtain from this book will not only prove valuable if you plan on performing or participating in wireless designs, but will also help you understand what makes WLANs tick, spot design mistakes, troubleshoot pesky clients and applications, understand and quantify RF issues, and more.

Writing a book on wireless design in order to certify career professionals on designing for any equipment vendor isn’t a light undertaking. Vendors differ in their approach. There are even different architectures that greatly vary in the way they work, which is certainly the case between equipment vendors, but major architectural differences can even be found between product lines from a single equipment vendor.

The approach taken with the CWDP is far deeper in one area in particular than any other CWNP curriculum has ever embarked upon before—RF. Radio frequency fundamentals is an extremely tough area to teach and is probably the single least understood area of wireless networking across technical professionals. This book aims to change some of that. After all, a house can’t be built on a bad foundation. A wired network can’t be built using bad cabling. A supersonic jet . . . you get the point. Without the proper foundation for a wireless LAN, the performance will suffer and your network may ultimately fail.

The total focus of this book isn’t just the wireless network infrastructure—we also explore the client devices that the wireless network infrastructure supports. In Wi-Fi, the communication link of a wireless client and an AP must be in parity with each other. For example, if you switch phones, even with the same mobile network carrier, your experience will vary. Where you may have once had good reception, you won’t now, and vice versa. It is no different with Wi-Fi. In fact, it is worse. Mobile network carriers have incredible control over the phones they will support and perform a great deal of engineering before placing them into the hands of customers. Wi-Fi, on the other hand, has many different equipment infrastructure vendors, an even greater disparity of operating modes, and a far greater variety of client devices with comparatively very little rigor and testing between them. Industry standards have a lot of wiggle room, and as a wireless network designer, you need to take this fact into account from the onset. After all, the very reason a wireless network exists is to support client devices.

If you have purchased this book or if you are thinking about purchasing this book, you probably have some interest in taking the CWDP® (Certified Wireless Design Professional) certification exam or in learning more about what the CWDP certification exam is about. We would like to congratulate you on this first step, and we hope that our book can help you on your journey. Wireless networking is one of the hottest technologies available today and demands for mobility are great among a wide variety of industries. As with many fast-growing technologies, the demand for knowledgeable people is often greater than the supply. The CWDP certification is your opportunity to distinguish yourself from others and a way to prove that you have the knowledge and skills to support this growing industry. This Study Guide was written with that goal in mind.

This book will teach you about wireless networking so that you have the knowledge needed not only to pass the CWDP certification test, but also to be able to design, install, and support wireless networks. We have included review questions at the end of each chapter to help you test your knowledge and prepare for the test.

Before we tell you about the certification process and requirements, we must mention that this information may have changed by the time you are taking your test. We recommend that you visit www.cwnp.com as you prepare to study for your test to determine what the current objectives and requirements are.

To adequately study for the CWDP exam, you need to do more than just study the questions and answers in this book! The practice questions we have supplied are designed to test your knowledge of a concept or objective that is likely to be on the CWDP exam, but to really learn this material, you need to read and study the chapters in the book. Please note that the practice questions will be different from the actual certification questions, but if you learn and understand the topics and objectives, you will be better prepared for the test.