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Cisco press deploying voice over wireless LANs mar 2007 ISBN 1587052318

DeployingVoiceoverWirelessLANs
byJimGeier
Publisher:CiscoPress
PubDate:March14,2007
PrintISBN-10:1-58705-231-8
PrintISBN-13:978-1-58705-231-6
Pages:264
TableofContents|Index

Overview
DeployingVoiceoverWirelessLANs
Thedefinitiveguidetoplanning,architecting,deploying,
supporting,andcreatingVoiceoverWirelessLANsolutions
Recentadvancesmakeitpossibletodeliverhigh-qualityvoice
andvideocommunicationsoverawirelessLAN(WLAN),
replacingcostlywiredtelephoneandvideosurveillancesystems
anddramaticallyreducingsupportcosts.However,today'snew
voiceoverWLAN(VoWLAN)technologiesrequirefundamentally
differentskillsandtechniquesfromthoseusedintraditional
voiceandvideosystems.Now,there'sacompleteguideto
everyfacetofVoWLANdeployment:planning,design,

installation,security,maintenance,andtroubleshooting.
AuthoredbywirelessindustryexpertandleaderJimGeier,
DeployingVoiceoverWirelessLANsdrawsonGeier'sextensive
experiencewithreal-worldVoWLANdeployments.Geierbrings
togetherstate-of-the-artinsightsintoVoWLANtechnologies,
standards,products,services,implementationstrategies,and
muchmore.
Geierbeginsbyintroducingkeycomponentsoftoday'sVoWLAN
systems,includingphones,clientsoftware,andvoice
encoders/decoders,aswellasVoWLANsignalingessentialssuch


asanalog-to-digital(A/D)conversionandcompression.Using
examplesdrawnfromactualenterprisesettings,you'lllearn
exactlyhowVoWLANproductsintegratewithexistingIP
infrastructure.
Next,heintroducescrucialemerging802.11standardsfor
effectiveVoWLANdeployment,including802.11equalityof
service(QoS)standards,802.11rtominimizepacketloss
betweenaccesspoints,and802.11knetworkdiscovery.He
carefullyreviewsthesecurityimplicationsofVoWLANvoice,
systematicallycoveringbothrisksandcountermeasures.Finally,
Geierwalksthroughimplementationfromstarttofinish,
thoroughlycoveringanalysis,design,installation,configuration,
testing,andsupport.
Whateveryourroleinplanning,delivering,managing,or
creatingwirelessvoiceandvideosolutions,DeployingVoice
overWirelessLANsisyourmostcomprehensive,authoritative
resource.
JimGeierfoundedWireless-Nets,Ltd.,andservesasits
principalconsultant.His25yearsofexperienceincludesthe
analysis,design,softwaredevelopment,installation,and
supportofnumerouswirelessnetworkingsystems.Hehasbeen
activewithintheWi-FiAllianceandtheIEEE802.11Working
GroupandhelpeddevelopinternationalstandardsforWLANs.
HisbooksincludeWirelessNetworksFirstStep(CiscoPress),
WirelessLANs(Sams),WirelessNetworkingHandbook(MTP),
andNetworkReengineering.
UnderstandVoWLANcomponents,applications,andbenefits
SeeVoWLANatworkinactualenterpriseenvironments
MasterVoWLANsignaling,includingvoicesignal
characteristics,A/Dconversion,andcompression
Discoverthelatest802.11VoWLANstandards,including
802.11e,802.11r,and802.11k


SecureIP-basedVoWLANsystemsagainstintrusionand
compromise
Analyzeyourorganization'srequirementsanddesignan
optimalVoWLANsolution
Planforcapacity,roaming,andintegrationwithcellular
systems
Install,configure,test,verify,andvalidateyourVoWLAN
system
Planforoperationalsupportandimplementappropriate
administrationtoolsandmethods
IncludesacompleteVoWLANglossary
PartIFundamentalElements
Chapter1VoWLANApplicationsandBenefits
Chapter2VoWLANSystemComponents
Chapter3VoWLANSignalingFundamentals
Chapter4WirelessLANTechnologies
Chapter5VoWLANSecuritySolutions
Chapter6AnalyzingVoWLANRequirements
Chapter7DesigningaVoWLANSolution
Chapter8Installing,Configuring,andTestingaVoWLAN
System
Chapter9SupportingaVoWLANSystem
AppendixAAnswerstoChapterReviewQuestions
Glossary
ThisbookispartoftheNetworkingTechnologySeriesfrom
CiscoPress®,whichoffersnetworkingprofessionalsvaluable


informationforconstructingefficientnetworks,understanding
newtechnologies,andbuildingsuccessfulcareers.
Category:CiscoPress–Networking
Covers:VoiceoverWirelessLANSolutions


DeployingVoiceoverWirelessLANs
byJimGeier
Publisher:CiscoPress
PubDate:March14,2007
PrintISBN-10:1-58705-231-8
PrintISBN-13:978-1-58705-231-6
Pages:264
TableofContents|Index

Copyright
AbouttheAuthor
Acknowledgments
IconsUsedinThisBook
CommandSyntaxConventions
Introduction
PartI:FundamentalElements
Chapter1.VoWLANApplicationsandBenefits
TheRoleofVoWLANSolutions
HistoryofVoWLANs
Healthcare
Enterprises
Universities
Retail
Warehouses
Manufacturing
SmallOfficesandHomes
SecuritySystems
DeterminingROI
ChapterSummary
ChapterReviewQuestions
Chapter2.VoWLANSystemComponents


VoWLANSystemOverview
Cisco7920WirelessIPPhone
CiscoIPSoftphone
CiscoCallManager
CiscoCallManagerExpress
LinksysWi-FiVideoCameras
WirelessNetworkInfrastructures
ChapterSummary
ChapterReviewQuestions
Chapter3.VoWLANSignalingFundamentals
VoiceAttributes
VideoAttributes
VoIPCallFlow
RadioFrequency(RF)Signals
WirelessImpairments
ChapterSummary
ChapterReviewQuestions
PartII:CriticalTechnologies
Chapter4.WirelessLANTechnologies
InfrastructureMode
AdHocMode
WirelessMediumAccess
802.11PhysicalLayerStandards
WirelessConfigurationParameters
ChapterSummary
ChapterReviewQuestions
Chapter5.VoWLANSecuritySolutions
SecurityImplications
Encryption
Authentication
TipsforEnhancingSecurity
ChapterSummary


ChapterReviewQuestions
PartIII:ImplementationSteps
Chapter6.AnalyzingVoWLANRequirements
OverallRequirementsAnalysisSteps
IdentifyingPotentialRequirements
VerifyingandValidatingRequirements
DocumentingRequirements
ChapterSummary
ChapterReviewQuestions
Chapter7.DesigningaVoWLANSolution
OverallDesignSteps
DeploymentModels
Roaming
Security
NetworkInfrastructure
PlacementofAccessPoints
DocumentFindings
ChapterSummary
ChapterReviewQuestions
Chapter8.Installing,Configuring,andTestingaVoWLAN
System
InstallingAccessPoints
ConfiguringAccessPoints
InstallingandConfiguringCiscoCallManagerSoftware
ConfiguringWirelessIPPhones
VerifyingSystemOperation
ChapterSummary
ChapterReviewQuestions
Chapter9.SupportingaVoWLANSystem
ConfigurationManagement
NetworkMonitoring


SecurityAssessmentSteps
MaintenanceFunctions
EngineeringFunctions
HelpDeskPlanning
CiscoWorksWirelessLANSolutionEngine
ChapterSummary
ChapterReviewQuestions
AppendixA.AnswerstoChapterReviewQuestions
Chapter1
Chapter2
Chapter3
Chapter4
Chapter5
Chapter6
Chapter7
Chapter8
Chapter9
Glossary
|
A
B
C
D
E–F
G
H
I–J–K
L
M
N
O
P


Q–R
S
T
U–V
W–Z
Index


Copyright
DeployingVoiceoverWirelessLANs
JimGeier
Copyright©2007CiscoSystems,Inc.
Publishedby:
CiscoPress
800East96thStreet
Indianapolis,IN46240USA
Allrightsreserved.Nopartofthisbookmaybereproducedor
transmittedinanyformorbyanymeans,electronicor
mechanical,includingphotocopying,recording,orbyany
informationstorageandretrievalsystem,withoutwritten
permissionfromthepublisher,exceptfortheinclusionofbrief
quotationsinareview.
PrintedintheUnitedStatesofAmerica1234567890
FirstPrintingMarch2007
LibraryofCongressCataloging-in-PublicationNumber:
2004117087
ISBN-13:978-1-58705-231-6

TrademarkAcknowledgments
Alltermsmentionedinthisbookthatareknowntobe
trademarksorservicemarkshavebeenappropriately
capitalized.CiscoPressorCiscoSystems,Inc.cannotattestto
theaccuracyofthisinformation.Useofaterminthisbook
shouldnotberegardedasaffectingthevalidityofany
trademarkorservicemark.

WarningandDisclaimer
Thisbookisdesignedtoprovideinformationaboutthe


technologiesandimplementationstrategiesfordeployingvoice
overwirelessLANs.Everyefforthasbeenmadetomakethis
bookascompleteandasaccurateaspossible,butnowarranty
orfitnessisimplied.
Theinformationisprovidedonan"asis"basis.Theauthor,
CiscoPress,andCiscoSystems,Inc.shallhaveneitherliability
norresponsibilitytoanypersonorentitywithrespecttoany
lossordamagesarisingfromtheinformationcontainedinthis
bookorfromtheuseofthediscsorprogramsthatmay
accompanyit.
Theopinionsexpressedinthisbookbelongtotheauthorand
arenotnecessarilythoseofCiscoSystems,Inc.

CorporateandGovernmentSales
CiscoPressoffersexcellentdiscountsonthisbookwhen
orderedinquantityforbulkpurchasesorspecialsales.

Formoreinformationpleasecontact:U.S.CorporateandGovernmentS
800-382-3419
corpsales@pearsontechgroup.com

ForsalesoutsidetheU.S.pleasecontact:InternationalSalesinternation

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Dedication
ThisbookisdedicatedtoMadisonandKimberlyn.


AbouttheAuthor
JimGeieristhefounderofWireless-Nets,Ltd.,andthe
company'sprincipalconsultant.His25yearsofexperience
includestheanalysis,design,softwaredevelopment,
installation,andsupportofnumerouswirelessnetwork-based
systemsforenterprises,airports,homes,retailstores,
manufacturingfacilities,warehouses,hospitals,andcities
worldwide.
JimhasbeenactivewithintheWi-FiAlliance,responsiblefor
certifyinginteroperabilityof802.11(Wi-Fi)wirelessLANs.He
hasalsobeenactivewiththeIEEE802.11WorkingGroup,
responsiblefordevelopinginternationalstandardsforwireless
LANs.HeservedasChairmanoftheIEEEComputerSociety,
DaytonSection,andChairmanoftheIEEEInternational
ConferenceonWirelessLANImplementation.Jimisanadvisory
boardmemberofseveralleadingwirelessLANcompanies.
Jimistheauthorofseveralbooks,includingWirelessNetworks
FirstStep(CiscoPress),WirelessLANs(Sams),Wireless
NetworkingHandbook(MTP),andNetworkReengineering
(McGraw-Hill),aswellasnumerousarticles.
Jim'seducationincludesabachelor'sandmaster'sdegreein
electricalengineeringandamaster'sdegreeinbusiness
administration.
ContactJimGeieratjimgeier@wireless-nets.com.

AbouttheTechnicalReviewers
ShawnMerdingerisanindependentsecurityresearcherand
consultantbasedinAustin,Texas.HewaspreviouslyaResearch
EngineerwiththeCiscoSecurityTechnologiesAssessmentTeam
(STAT)andTippingPoint,adivisionof3Com,wherehe
performedvulnerabilityassessmentsonavarietyofdevices,
technologies,andimplementations.


Mr.Merdingerholdsamaster'sdegreefromtheUniversityof
TexasatAustin,wherehisstudiesfocusedoncomputerand
networksecurity.HeiscurrentlyresearchingVoIPandis
developingtoolsandassessmentmethodologiestoaddress
VoIPsecurityissues.
JosephRothisalieutenantcommanderintheUnitedStates
Navy.Hecurrentlyisservingasthecommunicationsofficerfor
theNimitzStrikeGroup,whichrecentlycompletedasix-month
deploymenttothe5thFleet(MiddleEast)and7thFleet(Asia)
areaofoperations.Hisprevioustourwasasamilitaryprofessor
andNetworkSecurityGroupDepartmentHeadattheNaval
PostgraduateSchool(NPS).HeiscurrentlyaPh.D.candidatein
InformationSystemsatNovaSoutheasternUniversity.Heholds
fourmaster'sdegrees:computerscience(NPS),information
systemtechnology(NPS),publicadministration(Universityof
Maryland),andnationalsecurityandstrategicstudies(Naval
WarCollege).Josephalsoholdsabachelor'sdegreein
computerengineeringfromGeorgeWashingtonUniversityand
twocertificatesofhighereducationfromtheUniversityof
Cambridge.Hehasobtainednumerousindustrycertifications,
includingCCNA,CWNA,Security+,Network+,andMCP.His
articleshavebeenpublishedinInfoWorldandFederalComputer
Week.JosephservedinEuropeforfiveyearsandhasbeen
deployedtotheBalkansandBahrain.


Acknowledgments
IwouldliketogivespecialthankstoShawnMerdingerand
JosephRothforofferingtheirtechnicalwisdomduringthe
editingprocess.Theirfeedbackwasextremelyusefuland
enabledthecreationofagreatbook.
Also,Iwouldliketothanktheentireproductionteamfortheir
timeandeffortwiththisbook.Ihadmostcontactwith
ChristopherClevelandandDanYoung;theseguysareincredibly
professionalandfantasticeditors.AswithotherbooksthatI
havewrittenforCiscoPress,theproductionteamneverceases
toamazeme.Thanksforajobwelldone!


IconsUsedinThisBook
[Viewfullsizeimage]


CommandSyntaxConventions
Theconventionsusedtopresentcommandsyntaxinthisbook
arethesameconventionsusedintheIOSCommandReference.
TheCommandReferencedescribestheseconventionsas
follows:
Boldfaceindicatescommandsandkeywordsthatare
enteredliterallyasshown.Inactualconfigurationexamples
andoutput(notgeneralcommandsyntax),boldface
indicatescommandsthataremanuallyinputbytheuser
(suchasashowcommand).
Italicindicatesargumentsforwhichyousupplyactual
values.
Verticalbars(|)separatealternative,mutuallyexclusive
elements.
Squarebrackets[]indicateanoptionalelement.
Braces{}indicatearequiredchoice.
Braceswithinbrackets[{}]indicatearequiredchoice
withinanoptionalelement.


Introduction
Thisbookfocusesontechnologiesandimplementation
strategiesfordeployingvoiceoverwirelessLANs.Companies
havebeendeployingwirelessLANsformorethanadecade,but
recentadvancementsindataratesandqualityofservice
mechanismsareenablingcompaniestoeffectivelymake
integratedvoiceandvideocommunications(alongwith
commondataapplications)overwirelessLANsareplacement
fortraditional,relativelycostlywiredtelephoneandvideo
surveillancesystems.Thesignificantlylowersupportcosts,
combinedwithmobility,makevoiceandvideokiller
applications.Thedeploymentofawirelessvoiceandvideo
systemismuchdifferentfromtraditionalwiredandwireless
networks.Asaresult,thisbookisnecessarytoeducatereaders
onhowtodeployvoiceandvideosystems.Thisbookisbased
onpracticalexperiencethattheauthorhasgainedthrough
relatedreal-worldprojects.

WhoShouldReadThisBook?
Thisbookisintendedforreadershavingmoderateknowledgeof
networkingconceptsandprotocols.Forexample,thereader
shouldbefamiliarwithcommunicationsprotocols,handshaking
processes,andEthernetnetworkinfrastructures.Readers
shouldalsobeconversantwithcomputerterminology,suchas
local-areanetwork,client/server,andapplicationsoftware.
Thefollowingconstitutesthebook'sintendedaudience:
Informationtechnology(IT)staffandsystemintegrators
involvedwithanalyzing,designing,installing,and
supportingwirelessvoiceandvideosystems.
Engineersdevelopingvoiceandvideoproductsand
solutions.
Technicalprojectmanagersplanningandexecutingprojects


thatdeveloporinstallwirelessvoiceandvideoproductsor
systems.
Universityprofessorsandstudentslearningdetailsof
wirelessvoiceandvideosystemsinundergraduateor
graduate-levelcourses.

HowThisBookIsOrganized
Althoughthisbookcouldbereadcovertocover,itisdesigned
tobeflexibletoallowyoutoeasilymovebetweenchaptersand
sectionsofchapterstocoverjustthematerialthatyouneed
moreworkwithormoreinformationon.Thechapterscoverthe
followingtopics:
PartI—FundamentalElements
-Chapter1,"VoWLANApplicationsand
Benefits"—Thischapterdefinesallcomponentsthat
arepartofawirelessvoiceandvideosystem,suchas
phones,clientsoftware,andvoiceencoders/decoders.
Examplesofactualcomponentsaregiven,with
emphasisonCiscoproducts.Descriptionsofhow
multimediaintegrateswithexistingsystemsfoundin
enterprisesettingsarealsogiven.
-Chapter2,"VoWLANSystemComponents"—This
chapterdefinesallcomponentsthatarepartofa
wirelessvoicesystem,suchasphones,clientsoftware,
andvoiceencoders/decoders.Examplesofactual
componentsaregiven,withemphasisonCisco
products.Descriptionsofhowmultimediaintegrates
withexistingsystemsfoundinenterprisesettingsare
alsogiven.
-Chapter3,"VoWLANSignalingFundamentals"—
Thischapterprovidesanoverviewoftheprimary
elementsofvoicecommunications,suchasvoicesignal


characteristics,analog-to-digitalconversion,
compressiontechniques,andsoon.
PartII—CriticalTechnologies
-Chapter4,"WirelessLANTechnologies"—To
effectivelydesignawirelessLANthatsupportsvoice
applications,itisimportantthatreadersfully
understandthe802.11standard.Thischapterdescribes
standardelements,suchasMAClayerframesand
physicallayeroptions,andhowtheseelementsimpact
multimediaoperation.Specialattentionisgivento
optionsthatgovernthebehaviorofamultimedia
system.
-Chapter5,"VoWLANSecuritySolutions"—
Wirelessvoicesystemshaveuniquesecurity
implicationsthatsolutionprovidersmustrealizeand
offerapplicablecountermeasures.Thischapterexplains
securityissuesrelatedtovoicesystemsanddescribes
effectivemethodstoprovidesecuritythatmeets
relevantrequirements.
PartIII—ImplementationSteps
-Chapter6,"AnalyzingVoWLANRequirements"—
BeforedesigningawirelessLANthatsupportsvoice
applications,youmustfullyunderstandrequirements,
suchasnumberofusers,existingdatatraffic,roaming
needs,securityneeds,andanythingelsethatwill
provideabasisforthedesign.Adesignerusesthese
requirementswhendecidingwhichtechnologiestouse
andhowtoconfigurethenetwork.Thischapter
describeseachtypeofrequirementthatneedsdefinition
toimplementaqualitymultimediasystem.Thechapter
offersplentyofreal-worldexamplesandmethodsfor
determiningrequirements.


-Chapter7,"DesigningaVoWLANSolution"—This
chapterdiscussesthetechnicalelementsthatneed
considerationwhendesigningawirelessLANforvoice
applications.Thisincludesdeterminationoftechnology,
mechanismsforprovidingrequiredcapacity,optimum
802.11configurationsettings,roaming,andintegration
withcellularsystems.Thechapterprovidesexamplesof
whichtechnicalelementstoconsider,withspecific
requirementsinmind.
-Chapter8,"Installing,Configuring,andTestinga
VoWLANSystem"—Thischapterdefinesallnecessary
installationstepsandprovidesreal-worldtipsthat
minimizeriskswheninstallingthesystem.Thechapter
describesdetailsonthevarioustypesofteststhat
shouldberuntoverifyandvalidatethatthesystemis
meetingrequirementsandneedsoftheusers.
-Chapter9,"SupportingaVoWLANSystem"—
Wirelessvoicesystemsrequireuniquesupportpractices
andtools.Thischapterdiscussestheseelementsand
providesexamplesoftoolsandmethodsthatare
effectiveatsupportingthesystem.


PartI:FundamentalElements





Chapter1VoWLANApplicationsand
Benefits
Chapter2VoWLANSystemComponents
Chapter3VoWLANSignalingFundamentals


Chapter1.VoWLANApplicationsand
Benefits
Objectives
Uponcompletingthischapter,youwillbeableto
UnderstandtheroleofVoiceoverWirelessLANs
(VoWLAN).
DefineVoWLANapplications.
DetermineROIofaVoWLANsolution.
ThischapterdescribesvariousapplicationsofVoiceover
WirelessLAN(VoWLAN)systems.Real-worldexamplesandcase
studiesprovideyouwithasolidunderstandingofhowVoWLAN
canbenefitacompany.Detailsarealsogivenabouttangible
benefitsandexpectedreturnoninvestment(ROI).

TheRoleofVoWLANSolutions
VoWLANsystemsareanextensiontowiredVoiceoverInternet
Protocolsystemsandanalternativetotraditionalanalogand
digitalvoicecommunications.VoWLANsoffersignificantbenefits
ofprovidingmobilityandwirelesslyconvergingvoicewithdata
applications.WithVoWLANs,hospitals,enterprises,retail
stores,warehouses,andhomeownerscanreducetelephony
costsandenablemobileapplications.
ExamplesofthesystemsthatVoWLANscanreplaceincludethe
following:
Wiredtelephones
Cellulartelephones
Two-wayradios


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