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Chapter 2.  Planning, Design, Implementation, Operation, and Optimization Overview

Chapter 2.  Planning, Design, Implementation, Operation, and Optimization Overview

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withineachphase.



Figure2-1.PDIOOMethodologyforDeployingIPT

Solution



[Viewfullsizeimage]



AsshowninFigure2-1,thewholeprojecttypicallystartswith

thecustomerissuingaRequestforProposal(RFP).IPTvendors

respondwiththeIPTnetworkproposalbasedonthe

requirementsgivenintheRFP.Theplanningphasestarts

immediatelyafterthecustomerdecidesonaparticularvendor

solution.Chapter3,"Large-ScaleEnterpriseRequirementsfor

IPTelephony,"presentsthesampleRFP(thistaskisshownin

dottedlinesinFigure2-1)forafictitiouscustomer,XYZ,Inc.

Thesubsequentchaptersinthisbookcoverthevarioustasks

showninFigure2-1withinthePDIOOphasestorolloutIPTat



XYZ,Inc.Figure2-1showsthePDIOOtasksfordeployingthe

IPTsolutioninthedottedlines.NotethatFigure2-1showsthe

ommonlyfollowedtaskstodeployIPTbyfollowingthePDIOO

methodology.However,dependingonthetypeofthebusiness

andrequirements,youmighthavetoaddextrataskswithin

eachphase.



PlanningPhase

PlanningisthefirstphaseinthePDIOOlifecycle.Athorough

executionoftheplanningphasetaskslaysasolidfoundationfor

thedesignofanIPTnetwork.

Oneofthefirstimportanttasksintheplanningphaseisto

understandtheendcustomer'sexpectationsandrequirements.

Thesefallintotwomaincategories:

Businessexpectationsandrequirements

Technicalexpectationsandrequirements



Note

Thecustomerusuallyprovidesthebusinessand

technicalexpectationsandrequirementsintheRFP

document.Youshouldusetheinformationpresented

intheRFPfirstandthenconsultthevoicenetwork

architecturegroup,ITgroups,orothergroupsinthe

customer'sorganizationtoobtainadditional

information.



Fromthebusinessexpectationsandrequirementspointofview,

youshouldunderstandthecompany'sgoalsandvisionand

analyzehowtheserelatetothefutureIPTnetwork.More

particularly,informationthatmighthelpyoutoexecutethe

projectinatimelymannerandcompleteitwithintheprojected

budgetincludesthecompany'sgoalsforexpansioninthenext4

to6years,itscapitalexpenditures(CAPEX),itsoperational



expenditures(OPEX),itsreturnoninvestment(ROI),andits

expectationsregardinghowlongtheprojectshouldtaketo

plan,design,andimplement.

Fromthetechnicalexpectationsandrequirementspointofview,

youshouldunderstandthecompany'scurrentandfutureneeds

regardingIPTnetworkfeaturesandfunctionality.These

expectationsandrequirementsincludegeneralfeaturesthatare

requiredintheIPTnetwork,suchasnetworkredundancy,high

availability,convergence,security,networkmanagement,

applicationrequirements,utilization,performance,scaling

requirements,andsoforth.

Afteryouunderstandthesehigh-levelbusinessandtechnical

expectationsandrequirements,thenextphaseistoconducta

sitesurvey.Oneofthemostimportanttasksinthesitesurvey

istomeettherightgroupsofpeople(i.e.,LANgroup,WAN

group,IPnetworkgroup,legacyPBXandvoice-mailnetwork

group,applicationsgroup,etc.).Establishingtherightcontacts

helpsyoutoquicklyobtainaccurateinformationpertainingto

thenetwork.

Whileconductingthesitesurvey,youneedtoobtaindetails

regardingthefollowing:

ExistingLANinfrastructure,suchastheLANtopology,

equipmentdeployed,andcurrentLANQoSpolicies

WANinfrastructure,suchastheWANarchitecture,WAN

equipmentdeployed,existingQoSpolicies,trafficflows,

bandwidthassignments,andlinkutilizations

Layer3andLayer2infrastructure

IPaddressingscheme,includinghownetworkservicessuch

asDynamicHostConfigurationProtocol(DHCP)andDomain



NameSystem(DNS)aredeployed

Directoryandmessagingarchitecture

Layer3routingandroutedprotocolsusedinthenetwork

Legacytelephonyandvoice-mailinfrastructureand

telephonyfeaturessuchaspaging,operator,nightbell,call

center,MusiconHold,etc.deployedinthenetwork

Legacydialplanconfigurations

Currentutilizationandperformanceforvoiceanddata

networks

Currentnetworkmanagementinfrastructure

Currentday2supportandoperationssupportprocess

Afteryoucollecttheinformationbyconductingthesitesurveys,

youshouldperformadetailednetworkinfrastructure

assessmenttoensurethatthenetworkwillsupportIPT,that

newsystemsandapplicationswillbecompatiblewithexisting

systemsanddevices,andthatthenewIPTsystemwillperform

asplanned.Theinfrastructureassessmentshouldinclude

detailsregardinggapsintheinfrastructurethatneedtobefilled

tosupportIPTandrecommendationstostrengthenthe

infrastructuretosupporttheconvergednetwork.

Properexecutionoftheplanningphasewillleadtothe

following:

Realisticexpectationsofthescalability,performance,and

featuresofthenewIPTsystem



AnetworkinfrastructurethatisabletosupporttheIPT

traffic

Identificationofproperresourcestoacceleratetherolloutof

theIPTdeployment

AnIPTnetworkthatisalignedwithbusinessneeds

SuccessfulintegrationwithlegacyPBXandvoice-mail

systemsorcompletemigrationtoanIPTnetwork

DeploymentofIPTapplicationsandtheirintegrationwith

existingapplications

Chapter4,"PlanningPhase,"coverstheplanningphaseand

varioustasksinvolved.AppendixesB,"IPTPlanningPhase:

NetworkInfrastructureAnalysisQuestionnaire,"andC,"IPT

PlanningPhase:TelecomInfrastructureAnalysisQuestionnaire,"

includeNetworkInfrastructureandTelecomInfrastructure

AnalysisQuestionnaires,respectively,thatyoucanuseto

collecttheinformationrequiredintheplanningphaseandto

performthenetworkinfrastructureassessmentandgap

analysis.



DesignPhase

Afteryoucompletetheplanningphase,youshouldbegin

workingonthedesignphaseoftheIPTnetwork.Thegoalofthe

designphaseistoproposeanIPTnetworkdesignbyusingthe

informationthatiscollectedintheplanningphaseandthe

informationthatisprovidedbythecustomerintheRFP.You

alsoneedtocollectadditionalinformationthatisspecifictoIPT

featurerequirements.(RefertoAppendixesD,"IPTDesign

Phase:IPPhoneSelectionQuestionnaire,"andE,"IPTDesign

Phase:IPTRequirementAnalysisQuestionnaire,"fortheIPT

DesignPhaseQuestionnaires).

Youshouldconsiderseveraldifferentdesignalternativesbefore

arrivingatthefinaldesign.Thisproposeddesignshouldcater

tothecompany'scurrentandfutureIPTneeds.

Thedesignphaseconsistsofthefollowinghigh-leveltasks,

throughwhichdifferentcriticalareasofthenetworkare

designedbasedonIPTnetworkneeds:

Networkinfrastructuredesign

Designofcall-processinginfrastructureandapplications

Softwareversionevaluation

Designvalidation

AsshowninFigure2-1,thegoalofthedesignphaseisto

completetheprecedingfourdesignphasetasksandprovidethe

designdocumentthatproposesanIPTnetworkdesignthat

satisfiesthecustomer'sneeds.Thedesigndocumentshould

includetheproposedIPTnetworkarchitecturediagrams,



recommendedconfigurationsforvoicegateways,QoS

recommendationsforLAN/WAN,etc.Chapters5,6,and7cover

theprecedingfourtasksinvolvedinthedesignphaseand

explaintheindividualtaskswiththehelpofthecasestudy.

IPTnetworkdesignersshouldreviewthisdesigndocumentwith

thevoicenetworkarchitectureteamandinfrastructuregroups

inthecustomer'sorganizationtoensurethattheproposed

designmeetstheirrequirements.



NetworkInfrastructureDesign

Thefirsttaskofthedesignphaseistoenabletheexisting

networkinfrastructuretosupportIPT.Chapter5discussesthe

networkinfrastructuredesigntasksandfocusesonthe

followingdesignareas:

ChoosingtheIPTdeploymentmodel

DesigninganIPaddressingscheme,voiceVLANsforIPT

networkdevices,andIProuting

EvaluatingandselectingCiscoIPphonemodels

DesigningDHCPandTFTPservicesforCiscoIPphonesand

otherIPTendpointsinadditiontotheuseofDNSservices

Designingqualityofservice(QoS)intheLAN

Choosingthein-linepowerstandardanddeterminingthe

additionalhardwareneedsontheswitchesandthepower

requirements

DesigningtheLANandWANinfrastructureforresiliency



SizingtheWANlinksanddesignofQoSintheWAN



DesignofCallProcessingInfrastructureand

Applications

Thesecondtaskofthedesignphaseistochooseandsizethe

IPTcomponents,reviewandmakerecommendationsto

integrateormigratecurrenttelephonyapplicationswithorto

newIPTapplicationsbasedoncustomer'stelephony

requirements.Chapters6and7discussthefollowingdesign

tasks:

SizingtheCallManagerclusters

Sizingthevoicegatewaysandgatekeeper

PreparingtheIPTsystemtointegrateoraccessthe

corporateLightweightDirectoryAccessProtocol(LDAP)

directory

Designingdialplan

Choosingtherightdesignstepstomigrateorintegratewith

thelegacysystems(PBX,key,voicemail,orunified

messagingsystem)

IncorporatingthefaxandmodemrequirementsintheIPT

network

Deployingtheconferencingandtranscodingresourcesand

sizingthembasedontherequirements

Recommendingthesecurityandnetworkmanagement



solutions

CustomizingandsizingtheIPTapplicationssuchasAuto

Attendant(AA)andcallcenterapplicationIP-ICD

(IntegratedContactDistribution)

Designingandcustomizingthevoicemailsystem



SoftwareVersionEvaluation



Aswithanyotherproducts,theCiscoIPTproductshave

undergonemanysoftwarerevisions.Newversionsincludebug

fixestotheoldversionsandmanynewfeatures.Theheartof

theCiscoIPTsolutionisCiscoCallManager.Itinterfaceswith

otherapplicationsasdescribedintheprecedingsectionto

provideadditionalfeaturesandcapabilities.Youshouldreferto

theCiscoCallManagerCompatibilityMatrixavailableon

Cisco.comtoensurethatallthesoftwareversionsontheother

IPTendpointssuchasIPPhones,voicegateways,and

applicationsarecompatiblewiththeCallManagerversionchosen

forthedeployment.TheCiscoCallManagerCompatibilityMatrix

isavailableat

http://www.cisco.com/univercd/cc/td/doc/product/voice/c_callmg/ccmcom



DesignValidation

Thefinaltaskofthedesignphaseistovalidatetheproposed

designbybuildingaproofofconcept(POC)labandconducting

theacceptancetesting.ThePOClabtopologythatyoudesign

shouldemulatetheproposednetworkandmustcontainallthe

differentIPTcomponentsthatareproposedintheactual

design.

ThisacceptancetestingisnecessaryforasmoothrolloutofIPT



throughouttheentirenetwork.Toensurethis,you,alongwith

thecustomertechnicalteam,shoulddevelopatestplanthat

clearlydefinesvariousuniquetestscenariosandthenexecute

thetestplan.Typicalscenariosincludetestingthefollowing:

Internalandexternalphonecalls

Conferencecalls

IPTfeaturesthataredeployed

Failoverscenarios

CallsbetweenthesitesacrosstheWAN

Calladmissioncontrolfeature

WANcircuitfailureconditions

RecoverytimesforfailureswithintheLAN

Accesstovoicemailandmessagenotification

Voice-mail/PBXintegration

Callroutingandcallingprivileges

Systemrestorationfromthebackupdata

Whileyouaregoingthroughthisexercise,thetimethatyou

devotemustbereasonableenoughtocoverallthetest

scenariosdescribedinthetestplan.Followingaresomeclear

advantagesofgoingthroughthisexercise:



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