Cisco press cisco IP telephony planning design implementation operation and optimization mar 2005 ISBN 1587051575

CiscoIPTelephony:Planning,Design,
Implementation,Operation,andOptimization
ByRameshKaza,SalmanAsadullah

Publisher :CiscoPress
PubDate :February23,2005
ISBN :1-58705-157-5
Pages :672

Thecomprehensiveguidetoplanningandimplementingyour
CiscoIPTelephonysystem,asshownbytheexperts.
Understandhowtoworkthroughthedifferent
implementationphasesofaCiscoIPtelephonysolution
Planyourimplementationwithtoolsandguidesfromthe
mostseasonedexpertsintheindustry




Tableof
•
Contents
• Index

Avoidpitfallsintheprocesswithbest-practicesuggestions
andothertipsderivedfromyearsofactualimplementation
experience
CiscoIPTelephony:Planning,Design,Implementation,and
OperationoftheIPTelephonyNetwork,isaguidefornetwork
engineersastheygothroughthedeploymentofaCiscoIP
telephony(IPT)solution.AlthoughanIPTsystembringsseveral

benefitstoanorganization,understandingallthecomponentsof
thatsystemisnecessaryforasuccessfulimplementation.
Engineerstaskedwithimplementationmustalsokeepinmind
thatthearchitecturetheyareinstallingmustbescalableinthe
future.Theauthorsofthisbook,RameshKazaandSalman
Asadullah,havetakenanapproachtoaddressthequestionsthat
cometotheseengineerswhileplanning,designing,implementing,
andoperatingtheCiscoIPTsolutions.Thedeploymentprocess
hasbeendividedintofourphases:Planning,Design,
Implementation,andOperation(PDIO).Eachphaseprovides
specificdetailsaboutthetasksinvolvedandbestpracticesfor
successfulimplementationoftheIPTsolution.
Thisbookalsocontainspre-designedquestionnairesand
assistancetoolsthatwillhelpengineersdeterminethe
requirementsofeachphaseofthePDIOcycle.Thisbookis
writtenbyexpertsfromCiscowithextensiveexperiencein
implementingthesesolutions.Readersareprovidedstep-by-step
explanations,specificdetails,andbestpracticesacquiredbythe


authorswhileworkingwiththetopCiscoIPTcustomers.

CiscoIPTelephony:Planning,Design,
Implementation,Operation,andOptimization
ByRameshKaza,SalmanAsadullah

Publisher :CiscoPress

PubDate :February23,2005
Tableof
•
ISBN :1-58705-157-5
Contents
Pages :672

• Index





















Copyright
AbouttheAuthors
AbouttheTechnicalReviewers
Acknowledgments
ThisBookIsSafariEnabled
Foreword
Introduction
GoalsandMethods

TargetCallManagerRelease
HowThisBookIsOrganized
HowtoReadThisBook
PartI:OverviewofTechnology,Protocols,andthePDIOOMethodology
Chapter1.CiscoIPTelephonySolutionOverview
LegacyVoiceandDataNetworks
Next-GenerationMultiserviceNetworks
NetworksBasedonCiscoAVVID
SignalingandTransportProtocols
IPTelephonyComponents
IPTelephonyDeploymentArchitectures
Call-FlowScenarios
Summary
Chapter2.Planning,Design,Implementation,Operation,andOptimization
Overview
PlanningPhase
DesignPhase

ImplementationPhase
OperationandOptimizationPhase
Summary
PartII:Large-ScaleIPTandVoice-MailNetwork
Chapter3.Large-ScaleEnterpriseRequirementsforIPTelephony
CustomerProfile
CustomerRequirements
Summary
Chapter4.PlanningPhase
GettingStarted
NetworkInfrastructureAnalysis
TelecomInfrastructureAnalysis
Summary
Chapter5.DesignPhase:NetworkInfrastructureDesign
Call-ProcessingArchitecture
IPPhoneSelection
NetworkInfrastructureDesignTasks
Summary
Chapter6.DesignofCall-ProcessingInfrastructureandApplications
High-LevelIPTDesign
Low-LevelDesign
FaxandModem

SecuringtheIPTInfrastructure
Summary
Chapter7.Voice-MailSystemDesign
DefiningtheVoice-MailSystemArchitecture
DesigningaCiscoUnitySystem
InstallingCiscoUnity
IntegratingVoiceMail
NetworkingOctelandUnity
CustomizingtheCiscoUnitySystem
MultipleDirectoryHandlers
ImprovingtheUserExperienceDuringMigration
Summary
Chapter8.Implementation
CompletePreimplementationTasks
PerformImplementationReadinessAnalysis
ImplementIPTComponents
IdentifytheImplementationTools

DeployIPTSolutionPilot
ImplementationAcceptanceTests
Post-ImplementationDocumentation
Day2Support
Training
Summary
Chapter9.OperationsandOptimization
SoftwareUpgrades
HardwareUpgrades
CallManagerOperationandMonitoringTools
OptimizationTips
Day2MonitoringandManagementTasks
IPTNetworkManagementTools
Summary
PartIII:Appendixes
AppendixA.CiscoIPPhoneModelsandSelectionCriteria
AppendixB.IPTPlanningPhase:NetworkInfrastructureAnalysis
Questionnaire
CustomerBusinessandTechnicalExpectations
NetworkDesign
NetworkServices
CablingandNetworkLinks
HardwareScalability
Software
PowerProtectionandEnvironmentalCondition
Security
AppendixC.IPTPlanningPhase:TelecomInfrastructureAnalysis

Questionnaire
PBXInfrastructure
AnalogDeviceInformation(Fax/Modem)
TrunkSizing
TelephonyNumberingPlan
Voice-MailInfrastructure
TelephonyFeaturesandApplications
ApplicationsSecurity
OperationsandMaintenance
AppendixD.IPTDesignPhase:IPPhoneSelectionQuestionnaire
UserRequirementsforPhoneFeatures
AppendixE.IPTDesignPhase:IPTRequirementAnalysisQuestionnaire

IPTelephonyDeploymentModel
CodecSelection

LegacyVoice-MailIntegrationRequirements
LegacyPBXIntegrationRequirements
SizingtheCallManagerCluster
BranchOfficeIPTRequirements
ClassofRestrictionRequirements
Call-RoutingandDialPlanRequirements
SizingthePSTN/GatewayTrunks
PowerRequirements(PerSite/PerSwitchSpecific)
CallAdmissionControlConsiderations
CorporateDirectoryRequirements
Conferencing,Transcoding,andMTPRequirementsforCentralSites
MusiconHoldRequirements
AppendixF.OrderingT1/E1PRIfromtheCarrierQuestionnaire
AppendixG.Voice-MailDesignQuestionnaire
Voice-MailRequirements
MessagingandDirectoryArchitecture
InfrastructureRequirementsforUnityDeployment
SizingtheUnityServer
UnityIntegrationwithPBX/CallManager
UnityNetworkingwithOtherVoice-MailSystems
AppendixH.IPTImplementationChecklist
PreimplementationTasks

ImplementationReadinessAnalysis
ConfigurationChecklistforInstallationofCallManagerandOtherApplication

Servers

AcceptanceTests

Index


Copyright
Copyright©2005CiscoSystems,Inc.
Publishedby:
CiscoPress
800East96thStreet
Indianapolis,IN46240USA
Allrightsreserved.Nopartofthisbookmaybereproducedor
transmittedinanyformorbyanymeans,electronicor
mechanical,includingphotocopying,recording,orbyany
informationstorageandretrievalsystem,withoutwritten
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quotationsinareview.
PrintedintheUnitedStatesofAmerica1234567890
FirstPrinting:February2005
LibraryofCongressCataloging-in-PublicationNumber:
2003108110

WarningandDisclaimer
ThisbookisdesignedtoprovideinformationaboutCiscoIP
Telephony.Everyefforthasbeenmadetomakethisbookas

completeandasaccurateaspossible,butnowarrantyor
fitnessisimplied.
Theinformationisprovidedonan"asis"basis.Theauthors,
CiscoPress,andCiscoSystems,Inc.shallhaveneitherliability
norresponsibilitytoanypersonorentitywithrespecttoany


lossordamagesarisingfromtheinformationcontainedinthis
bookorfromtheuseofthediscsorprogramsthatmay
accompanyit.
Theopinionsexpressedinthisbookbelongtotheauthorsand
arenotnecessarilythoseofCiscoSystems,Inc.

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

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PrintedintheUSA

Dedications
Formywifeforhertirelesssupportandencouragementinthis
project.Also,formydaughterandsonwhosacrificedtimewith
dadtomakethisbookhappen.
Ialsodedicatethisbooktomyfamilyfortheirnever-ending
support.
Ramesh
Idedicatethisbookto:
Thepeoplearoundtheworldwhoaresufferingandoppressed.
Myaffectionateparents,whogavemetheirbest,andtomy


lovingwife,forhersupportandencouragement.
Salman


AbouttheAuthors
RameshKaza,CCIENo.6207,isatechnicalleaderinthe
WorldWideVoicePracticeGroup(CustomerAdvocacy)atCisco

Systems.HehasbeenwithCiscoforfiveyears.Rameshhas
providedplanning,design,andimplementationsupporttomany
customersindeployingtheCiscoIPCommunicationssolutions.
PriortoworkingonIPCommunications,hewasinvolvedin
validatingthenetworkdesignsforenterpriseandservice
providercustomers.HeisaspeakerattheCiscoNetworkers
eventandhaspresentedtopicstitled"TroubleshootingIPT
Networks"and"DesigningLarge-ScaleIPTNetworks."Priorto
joiningCiscoSystems,RameshworkedforSoftwareTechnology
ParksofIndiaBangaloreasamemberofthetechnicalstaff,and
hehasplayedamajorroleinbuildingtheInternetbackbone.
Rameshholdsabachelor'sdegreeinelectronicsand
communicationsengineering.
SalmanAsadullah,CCIENo.2240,isatechnicalleaderat
CiscoSystems.AsarecognizedexpertwithinCiscoandthe
industry,hehasbeendesigningandtroubleshootinglarge-scale
IPandmultiservicenetworksformorethaneightyears.Salman
representsCiscoinindustrypaneldiscussionsandtechnical
platformssuchasNANOG,APRICOT,SANOG,ASEAN,IETF,IPv6
Forum,Networkers,andsoon.Salmaninfluencestechnology
directionsanddecisionswithCiscobusinessunitsandthe
Internetcommunity.Hehasproducedseveraltechnical
documentsandwhitepapersandisacoauthorofCiscoCCIE
Fundamentals:NetworkDesignandCaseStudies.Salmanhas
alsodevelopedCCIEexamsforIPandmultiservice
technologies.Heholdsabachelor'sdegreeinelectrical
engineeringfromTheUniversityofArizonaandamaster's
degreeinelectricalengineeringfromWichitaStateUniversity.

AbouttheTechnicalReviewers
NielsBrunsgaard,CCIENo.1544,hasbeenwithCisco
Systemsasaconsultingengineersince1999,specializinginIP
telephony.Hehasbeeninvolvedintheplanning,design,and
implementationofadozenIPtelephonynetworksthroughout
AsiaPacificandNorthAmerica.Nielsholdsabachelor'sdegree
inelectro-mechanicalengineeringfromtheDenmarkTechnical
UniversityinCopenhagen,andamaster'sdegreein
telecommunicationsfromtheUniversityofColorado.Heisa
doubleCCIE,withcertificationinvoiceinadditiontorouting
andswitching.
MarkGalloisatechnicalmanagerwithAmericaOnline,where
heleadsagroupofengineersresponsibleforthedesignand
deploymentofthedomesticcorporateintranet.Hisnetwork
certificationsincludeCiscoCCNPandCiscoCCDP.Hehasled
severalengineeringgroupsresponsiblefordesigningand
implementingenterpriseLANsandinternationalIPnetworks.He
hasaBSinelectricalengineeringfromtheUniversityof
Pittsburgh.MarkresidesinnorthernVirginiawithhiswife,
Betsy,andson,Paul.
AbderrahmaneMounir,CCIENo.4312,isanetwork
consultingengineerattheCiscoSystemsAdvancedServices
GroupinSanJose.Hehasbeenworkingwithlarge-scaleIP
telephonycustomersinplanning,designing,implementing,and
operatingIPtelephonynetworkssinceCallManagerrelease2.3.
Hehashelpedcustomerstosuccessfullydeployandmigrate
largeIPtelephonydeployments.HerepresentsCiscoby
presentingIPTend-to-endsolutionsandtroubleshooting
sessionsatNetworkersandotherinternalforums.Hehasalso
contributedtothecreationandthedesignoftheCCIEvoice

track.Abderrahmaneholdsabachelor'sdegreein
telecommunicationsengineeringandamaster'sdegreein


electricalandcomputerengineering.
GertVanderstraetenhasbeenworkingasatelecom/datacom
engineerforcompaniessuchasAlcatel,Bell,andLucent
Technologiessince1993.Between1998and2002,hewasan
independentcontractorfortheCiscoSystemsITdepartment.
Duringthisperiod,hismainfocuswastheimplementation,
maintenance,anddesignofVoIP,IPtelephony,voice,andvideo
applications,andtheintegrationofCiscoAVVIDtechnologies
intolarge-scalesolutions.InSeptember2002,hebecamea
memberofthetechnicalstaffandwasoperatinguntilMay2004
withintheCiscoSystemsglobalenterprisearchitecture
solutionsteam.GertiscurrentlyworkingintheAdvisory
Servicesteamasenterprisearchitect,wherehetakeson
responsibilityforlarge-scalecustomerdeployments.


Acknowledgments
FromRameshKazaandSalmanAsadullah:
Therearemanypeoplewhohelpedustomakethisproject
successful.Pleaseforgiveusifwehaveinadvertentlyomitted
thenameofanymorewhomadesuchhelpfulcontributions.
Thanksgotothefollowing:
HimanshuDesai,seniormanager,AdvancedServices;Mike
Quinn,VP,technicalsupport;KadirKoken,director,customer
advocacy;andKhalidRaza,CiscoDistinguishedEngineer,Cisco
Systems,Inc.,whoencouragedustowritethisbookand

supportedusthroughoutthisproject.
AbderrahmaneMounir,networkconsultingengineer,Cisco
Systems,Inc.,forcontributingtoChapter6,verifyingthe
configurationexamples,reviewingtheentirebook,and
providingvaluablefeedback.
GertVanderstraeten,enterprisearchitectfortheAdvisory
ServicesteamatCiscoSystems,Inc.,forcontributingto
Chapter7,reviewingtheentirebook,andprovidingvaluable
feedback.
RajeshRamarao,technicalleader,CiscoSystems,Inc.,forhis
contributionstopartsofChapter9.
JakeHartinger,technicalleader,CiscoSystems,Inc.,forhumbly
contributingtothevaluablequestionnairesinAppendixesBand
C.
NielsBrunsgaard,technicalleader,CiscoSystems,Inc.,for
reviewingpartsofthebookandprovidingvaluablesuggestions.
MarkGallo,technicalmanager,AmericaOnline,forreviewing


theentirebook,helpingincontentrearrangement,and
providingvaluablefeedback.
ThankstoallourcolleaguesandfriendsatCiscoSystems,Inc.
whoseworkhashelpedustocompletethisproject.Especially,
thankstothemembersoftheAdvancedServicesteam:Hymed
Besrour,Jine-Wen-Kou,TalalSiddiqui,OludareOdunuga(Tola),
DaveTurner,JohnVosburg,AlvinLaguerta,SanjayJani,Imran
Chaudhary,KathyDecker,andWesleyShuo.
Thankstoallthecustomerswithwhomwehaveworkedover
severalyearsandindoingsoacquiredvaluableknowledgeand
expertisethatwehavedocumentedinthisbook.

WewouldliketoexpressourspecialthankstoJohnKane,editor
inchief,forhisexpertguidance;AndrewCuppandJennifer
Foster,developmenteditors;BillMcManus,copyeditor;Tammi
Barnett,editorialassistant;andallotherstaffatCiscoPressfor
makingthispublicationpossible.


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Foreword
InOctober,1998,CiscotookastepforwardinitsentryintoIP
TelephonywiththeacquisitionofSelsiusSystems,apioneer
andinnovatorofnextgenerationnetworkPBXsystemsforhighqualitytelephonyoverIPnetworks.Thisbegantherevolutionof
convergeddata,voiceandvideonetworksrenderingseparate
voiceanddatanetworksathingofthepast.Ciscoisoneofthe
frontrunnersinchangingthewayenterprisesandservice

providersdeliverconvergingtraditionalvoice,data,andvideo
applications.
TheoverallIPcommunicationindustryhasgainedsignificant
momentum.TheoriginalSelsiusSystemsproductfamily
acquiredbyCiscohasexpandedandevolvedattremendous
speed.OverfourmillionIPphonesandoverthreemillionUnity
seatshavebeendeployed.
Inearly1999,Iwasaskedtobuildasmallteamofnetwork
consultingengineersinordertohelpCiscocustomersand
partnerswiththeplanning,designing,implementation,
operationandoptimization(PDIOO)ofIPcommunication
networksbyprovidingthemwithtemplates,toolsandbest
practices.SalmanAsadullahandRameshKazawereamongthe
firstfewseniorengineerswhoIaskedtohelpwiththistask.We
beganworkingwithourcustomersandduringthisprocesswe
definedthePDIOOprocessesforcorestepsthatarerequired
fordeployingIPcommunicationsolutions.Theseprocessesand
bestpracticesarebeingsharedinthisbookusinghypothetical
customerscenariosintheformofacasestudy.Aswithany
emergingtechnology,theseprocessesandbestpractices
changeoverthetime,buttheapproachappliedremainthe
same.Today,ourteamsupportssomeoflargestCiscoIP
communicationdeployments,somewithoverwith10,000IP
phones.Theteam,whichstartedwiththreenetworkconsulting


engineers,hasgrowntoover30engineersinthecourseoffour
years.
Oneday,SalmanandRameshwalkedintomyofficeand
presentedtheideaofwritingabookbasedontheexperience

weacquiredonthisrollercoasterride.Withthestrongtechnical
backgroundandexperiencetheygainedbyworkingwiththe
largestIPcommunicationsnetworks,itwasavaluableidea.
WhilereviewingtheirfinaldraftofthebookIwasimpressedto
seehowbeautifullytheyhavemadeanexcellentguideonhow
toapproachtheIPcommunicationprojectusingPDIOOlife
cycleforsmall-to-mediumsizedeployment.Iamconfidentthat
thereaderwillfindthisbookhighlyvaluableandpractical
becauseitcanbeusedasareferenceguidetocreatea
frameworkforyourIPcommunicationconvergenceprojects.
Regards,
HimanshuDesai
SeniorManager,AdvancedServices
IPCommunicationsServicesTeam


Introduction
IPtelephony(IPT)technologyhasgainedwideacceptancein
theindustrybecauseitoffersnewwaystocommunicateand
enablesrichmediacommunicationcapabilities.Recentstudies
haveshownthatdeploymentofIPTalsohelpsimprove
employeeproductivityasaresultoffastermoves,adds,and
changes;increasedusermobility;andreductioninthetimeto
setuptelecommunicationinfrastructurefornewofficespaces.
Theseareafewofthemanybenefitsthataremotivating
organizationstomovetoIP-basedPBXdeployments.
Successfuldeploymentofanynewtechnologysolutionrequires
thoroughunderstandingofthefunctionofvariouscomponents
involvedandtheinteractionamongthem.Thearchitectsand
engineerswhoaretaskedwithimplementingtheIPTsolution

mustensurethattheproposedarchitecturemeetsallthe
requirementsandisalsoscalableinthefuture.Toassistthe
architectsandengineersinaccomplishingthistask,thisbook
dividesthedeploymentofIPTintoplanning,design,
implementation,operation,andoptimization(PDIOO)phases.
Thisbookaddressesthemostimportantinformationthat
customers,networkengineers,andarchitectsshouldcollectin
eachphaseofthePDIOOmethodologyindeployingCiscoIPT
solutions.


GoalsandMethods
Thegoalofthisbookistobeausefulguidefornetwork
engineersandarchitectsgoingthroughthevariousphasesof
planninganddeployingaCiscoIPTsolution.Thisbookhelps
youtomakethedecisionsthatbestsuitaparticularnetwork
scenario.
ThemajortasksinvolvedineachphaseofthePDIOO
methodologyareexplainedwiththeaidofacasestudythat
includesthemostcommonlydeployedCiscoIPTarchitectures,
telephonyfeatures,andapplications.Youcanusethe
questionnairesintheappendixestocollectdetailsaboutthe
customer'scurrentnetworkandtogatherIPTrequirementsto
proposethemostsuitableIPTnetworkarchitectureanda
detaileddesign.
Tokeepthisbookconcise,in-depthdiscussionof
communicationprotocolsisnotincludedbecausethis
informationisreadilyavailableinotherbooksandinRequests
forComments(RFCs).

TargetCallManagerRelease
Thedesignprinciplesandguidelinesdiscussedinthisbookare
applicabletoCiscoCallManagerversion3.3.3andabove.With
thereleaseofnewversionsofCiscoCallManager,youmightfind
newfeaturesandscalabilityenhancements.However,thebasic
designrulesandthePDIOOmethodologyremainthesame.


HowThisBookIsOrganized
Thisbookisorganizedintothreeparts.
PartI,"OverviewofTechnology,Protocols,andthePDIOO
Methodology,"discussestheVoIPandIPTtechnologyand
relatedprotocols,mechanisms,architectures,andbasics.Italso
laysthefoundationofthePDIOOmethodologyanddiscusses
whythePDIOOmethodologyiscriticalforsuccessfulIPT
networkimplementation.PartIincludesthefollowing:
Chapter1,"CiscoIPTelephonySolutionOverview"
Chapter2,"Planning,Design,Implementation,Operation,
andOptimizationOverview"
PartII,"Large-ScaleIPTandVoice-MailNetwork,"buildsonthe
materialdiscussedinPartIandprovidesareal-worldexample
withtechnicaldetails,examples,designtips,andconfiguration
examplesateachphaseofthePDIOOmethodologyonhowto
buildasuccessfulandefficientlarge-scaleIPTnetworkfrom
scratch.PartIIincludesthefollowing:
Chapter3,"Large-ScaleEnterpriseRequirementsforIP
Telephony"
Chapter4,"PlanningPhase"
Chapter5,"DesignPhase:NetworkInfrastructureDesign"

Chapter6,"DesignofCall-ProcessingInfrastructureand
Applications"