Cisco press voice over IP fundamentals 2nd edition jul 2006 ISBN 1587052571

VoiceoverIPFundamentals,SecondEdition
ByJonathanDavidson,JamesPeters,ManojBhatia,
SatishKalidindi,SudiptoMukherjee
...............................................
Publisher:CiscoPress
PubDate:July27,2006
PrintISBN-10:1-58705-257-1
PrintISBN-13:978-1-58705-257-6
Pages:432

TableofContents|Index

AsystematicapproachtounderstandingthebasicsofvoiceoverIP

Understandthebasicsofenterpriseandpublictelephonynetworking,IPnetworking,
andhowvoiceistransportedoverIPnetworks
Learnthevariouscaveatsofconvergingvoiceanddatanetworks
ExaminethebasicVoIPsignalingprotocols(H.323,MGCP/H.248,SIP)andprimary
legacyvoicesignalingprotocols(ISDN,C7/SS7)
ExplorehowVoIPcanrunthesameapplicationsastheexistingtelephonysystem
butinamorecost-efficientandscalablemanner
DelveintosuchVoIPtopicsasjitter,latency,packetloss,codecs,QoStools,and
security

VoiceoverIP(VoIP)hasbecomeanimportantfactorinnetworkcommunications,
promisingloweroperationalcosts,greaterflexibility,andavarietyofenhanced
applications.TohelpyouunderstandVoIPnetworks,VoiceoverIPFundamentalsprovides
athoroughintroductiontothebasicsofVoIP.

VoiceoverIPFundamentalsexplainshowabasicIPtelephonyinfrastructureisbuiltand
workstoday,majorconceptsconcerningvoiceanddatanetworking,andtransmissionof

voiceoverdatanetworks.You'lllearnhowvoiceissignaledthroughlegacytelephone
networks,howIPsignalingprotocolsareusedtointeroperatewithcurrenttelephony
systems,andhowtoensuregoodvoicequalityusingqualityofservice(QoS).



EventhoughVoiceoverIPFundamentalsiswrittenforanyoneseekingtounderstandhow
touseIPtotransportvoice,itstargetaudiencecomprisesbothvoiceanddatanetworking
professionals.Inthepast,professionalsworkinginvoiceanddatanetworkingdidnothave
tounderstandeachother'sroles.However,inthisworldoftime-divisionmultiplexing
(TDM)andIPconvergence,itisimportanttounderstandhowthesetechnologieswork
together.VoiceoverIPFundamentalsexplainsallthedetailssothatvoiceexpertscan
understanddatanetworkinganddataexpertscanunderstandvoicenetworking.

Thesecondeditionofthisbest-sellingbookincludesnewchaptersontheimportanceof
billingandmediationinaVoIPnetwork,security,andthecommontypesofthreats
inherentwhenpacketvoiceenvironments,publicswitchedtelephonenetworks(PSTN),
andVoIPinteroperate.Italsoexplainsenterpriseandservice-providerapplicationsand
services.


VoiceoverIPFundamentals,SecondEdition
ByJonathanDavidson,JamesPeters,ManojBhatia,
SatishKalidindi,SudiptoMukherjee
...............................................
Publisher:CiscoPress
PubDate:July27,2006
PrintISBN-10:1-58705-257-1
PrintISBN-13:978-1-58705-257-6
Pages:432

TableofContents|Index

Copyright
AbouttheAuthors
AbouttheTechnicalReviewers
Acknowledgments
IconsUsedinThisBook
Introduction
PurposeofThisBook
WhoShouldReadThisBook?
ChapterOrganization
FeaturesandTextConventions
Timeliness
TheRoadAhead...
PartI:PSTN
Chapter1.OverviewofthePSTNandComparisonstoVoiceoverIP
TheBeginningofthePSTN
UnderstandingPSTNBasics
PSTNServicesandApplications
DriversBehindtheConvergenceBetweenVoiceandDataNetworking

PacketTelephonyNetworkDrivers
NewPSTNNetworkInfrastructureModel
Summary
Chapter2.EnterpriseTelephonyToday

SimilaritiesBetweenPSTNandET
DifferencesBetweenPSTNandET
CommonETandPSTNInterworking
Summary
Chapter3.BasicTelephonySignaling
SignalingOverview
E&MSignaling
CAS

ISDN
QSIG
DPNSS
Summary
Chapter4.SignalingSystem7
SS7NetworkArchitecture
SS7ProtocolOverview
SS7Examples
ListofSS7Specifications
Summary
Chapter5.PSTNServices
PlainOldTelephoneService
ServiceProviderServices
Summary
PartII:VoiceoverIPTechnology
Chapter6.IPTutorial
OSIReferenceModel
InternetProtocol
DataLinkLayerAddresses
IPAddressing
RoutingProtocols
EIGRP
IPTransportMechanisms
Summary
References
Chapter7.VoIP:AnIn-DepthAnalysis
Delay/Latency
Jitter
PulseCodeModulation
VoiceCompression

Echo



PacketLoss

VoiceActivityDetection
Digital-to-AnalogConversion
TandemEncoding
TransportProtocols
Dial-PlanDesign
EndOfficeSwitchCall-FlowVersusIPPhoneCall
Summary

References
Chapter8.QualityofService
QoSNetworkToolkit
EdgeFunctions
TrafficPolicing
BackboneNetworks
RulesofThumbforQoS
CiscoLabs'QoSTesting
Summary
Chapter9.BillingandMediationServices
BillingBasics
CaseStudy:CiscoSIPProxyServerandBilling
ChallengesforVoIPNetworks
MediationServices
Summary
Chapter10.VoiceSecurity
SecurityRequirements
SecurityTechnologies
ProtectingVoiceDevices
ProtectingIPNetworkInfrastructure
SecurityPlanningandPolicies
Summary
PartIII:IPSignalingProtocols
Chapter11.H.323
H.323Elements
H.323ProtocolSuite
H.323Call-Flows
Summary
Chapter12.SIP

SIPOverview




SIPMessageBuildingBlocks
BasicOperationofSIP

SIPProceduresforRegistrationandRouting
SIPExtensions
Summary
Chapter13.GatewayControlProtocols
MGCPOverview
MGCPModel
MGCPCommandsandMessages
MGCPCallFlows

AdvancedMGCPFeatures
H.248/MEGACO
Summary
PartIV:VoIPApplicationsandServices
Chapter14.PSTNandVoIPInterworking
CiscoPacketTelephony
PacketVoiceNetworkOverview
PGW2200ArchitectureandOperations
PGW2200Implementation
PSTNSignalingOverIP
ChangingLandscapeofPSTN-IPInterworking
SessionBorderController(SBC)
Summary
Chapter15.ServiceProviderVoIPApplicationsandServices
TheServiceProviderDilemma
ServiceProviderApplicationsandBenefits
ServiceProviderVoIPDeployment:Vonage
ServiceProviderCaseStudy:PrepaidCallingCard
SessionBorderControl:ValueAddition
VoIPPeering:TopPriorityfortheServiceProviders
ServiceProviderVoIPandConsumerFixedMobileConvergence
Summary
Chapter16.EnterpriseVoiceoverIPApplicationsandServices
MigratingtoVoIPArchitecture
EnterpriseVoiceApplicationsandBenefits
AdvancedEnterpriseApplications
Wi-FiEnabledPhones

BetterVoiceQualityUsingWidebandCodecs



Summary



Index


Copyright
JonathanDavidson,JamesPeters,ManojBhatia,Satish
Kalidindi,andSudiptoMukherjee
Copyright©2007CiscoSystems,Inc.
Publishedby:
CiscoPress
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Allrightsreserved.Nopartofthisbookmaybereproducedor
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mechanical,includingphotocopying,recording,orbyany
informationstorageandretrievalsystem,withoutwritten
permissionfromthepublisher,exceptfortheinclusionofbrief
quotationsinareview.
PrintedintheUnitedStatesofAmerica1234567890
FirstPrintingJuly2006
LibraryofCongressCataloging-in-PublicationNumber:
2005934132

WarningandDisclaimer
Thisbookisdesignedtoprovideinformationaboutthe
fundamentalsofVoiceoverIP(VoIP).Everyefforthasbeen
madetomakethisbookascompleteandasaccurateas
possible,butnowarrantyorfitnessisimplied.
Theinformationisprovidedonan"asis"basis.Theauthors,
CiscoPress,andCiscoSystems,Inc.shallhaveneitherliability


norresponsibilitytoanypersonorentitywithrespecttoany
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Theopinionsexpressedinthisbookbelongtotheauthorand
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Wegreatlyappreciateyourassistance.

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AbouttheAuthors
JonathanDavidson,CCIENo.2560,istheDirectorofSP
SolutionEngineeringinIntegratedNetworkSystems
Engineering.HehascoauthoredVoiceoverIPFundamentals
andeditedDeployingCiscoVoiceoverIP.Hehasbeenwith
Ciscofor10yearsinpostsalessupport,marketing,and

engineeringdivisions.
JamesPetersistheDirectorofProductMarketinginthe
CarrierCoreandMultiserviceBusinessUnitatCiscoSystems.
HecoauthoredthefirsteditionofVoiceoverIPFundamentals
andiscurrentlyauthoringabookonmultiservicenetworking.
Jameshasmorethan20yearsexperienceinbuildingand
designingInternet-basedvoiceanddatanetworks,andproduct
development.
ManojBhatiaisaBusinessDevelopmentManagerforPartner
ProgramsatIPCommunicationsBusinessUnit(IPCBU)forCisco
Systems,Inc.Hewasamongthefirsttostartthesoftware
developmentforSIPtechnologyonCiscoVoIPgatewaysand
IOS-basedrouters.Hispastprojectsincludetechnical
marketingforVoIPproductssuchasmediagateways,call
agents,andSIP-basedresidentialvoicesolutions.PriortoCisco,
ManojworkedinNortelNetworksandSummaFour(nowCisco)
andhas14+yearsofexperienceintelephonyprotocolssuchas
SS7,callcontrol,andVoIPtechnologies.
SatishKalidindiisaSoftwareEngineerwithCiscoSystems.
Hehasmorethansixyearsexperienceworkingondevelopment
anddeploymentofVoIPtechnologies.Hehasbeeninvolved
withvariousproducts,includingIOSgatewaysandCisco
CallManager.Morerecentlyhehasbeeninvolvedwithsecurity
featuresonCCM.HeisagraduateofPurdueUniversitywithan
M.S.inengineering.


SudiptoMukherjeeisaSoftwareDevelopmentEngineerwith
CiscoSystems.Hehasproductdevelopmentanddeployment
experienceforavarietyoftelecommunicationdevicesfor

wireline,wireless,andVoIPnetworks.MorerecentlyatCiscohe
hasbeenworkingonSIPgatewaydevelopment.Sudiptohasa
bachelorsofengineeringdegreeinelectronicscommunication
engineeringfromGSInstituteofTechnology,Indore,anda
mastersdegreeinelectronicsdesignandtechnologyfrom
IndianInstituteofScience,Bangalore.




AbouttheTechnicalReviewers
BrianGracely,CCIENo.3077,isaTechnicalLeaderfor
Cisco/LinksysSmallBusinessSystemsBusinessUnit.Heis
responsiblefortheoverallsolutionarchitectureoftheLinksys
Onesolution,whichtargetsconvergednetworkingforsmall
businesses.HehasbeenwithCiscofor10yearsandhas
workedinanumberofdesign,engineering,marketing,and
supportpositions.HewasacoauthorofthefirsteditionofVoice
overIPFundamentals.
JesseJ.HerreraisaSeniorSystemsAnalystforaFortune100
companylocatedinHouston,Texas.Mr.Herreraholdsa
bachelorofscienceincomputersciencefromtheUniversityof
Arizonaandamasterofscienceintelecommunications
managementfromSouthernMethodistUniversity.
Responsibilitieshaveincludeddesignandimplementationof
enterprisenetworkarchitectures,includingcapacityplanning,
performancemonitoring,andnetworkintegrationservices.
Recentactivitiesincludewirelessandvirtualprivatenetwork
initiativesandsupportofelectronicbusinessservices.
BrionS.Washington,CCNA,hasmorethan10years

internetworkingexperience,withthelast4yearsdedicatedto
VoIP.HeisstudyingnowforhissecondR/Slabattemptandfor
theCCVPcertification.HelivesintheMidwest,whereheworks
asanetworkconsultant.


Acknowledgments
JonathanDavidson:
I'dliketogivespecialrecognitiontoJohnKaneforworkingso
diligentlyandpatientlywhileweputtogetherthissecond
edition.IalsowouldliketothankManojBhatia,Satish
Kalidindi,andSudiptoMukherjeeformakingthissecondedition
possible.
Ialsowouldliketoonceagainthankmychildren,Meganand
Ethan,forputtingupwithadadalwaystypingonhislaptop.
Youtwoarethebest.
ManojBhatia:
IwouldliketothanktheCiscopressteam,mycoauthorsand
reviewers,andChrisLosack,mymanager,forencouragingme
inthiseffort.
IalsowouldliketothankmywifeAnu,andmykids,Dhvani
andRhythm,forkeepingupwithmeduringlong-haulhoursof
researchandtypingforthetopics.Ihopetheyaremuchmore
awareofthebuzzwordVoIP,astheyarethetrueusersofVoIP
nowandintheyearstocome!
SatishKalidindi:
IwouldliketoacknowledgeJohnKaneandtheeditorialteamat
CiscoPressfortheirconcertedeffortsandencouragement.
Thankstoreviewersandmycoauthorsfortheirdiligentwork.
ThanksalsotomywifeValli,forbearingwithmeovermany

longnights.
SudiptoMukherjee:


Ithankmycoauthors,reviewers,andmymanager,Kimberly
Quinn,forprovidingsupportandencouragement.Special
thankstotheCiscoPressteamforitspatienceand
understandingasthematerialcametogether.
Ithankmyparentsfortheirencouragementandsupport.
IthankmywifeChandrima,andchildren,Shreyasiand
Joydeep,fortheirloveandsupportwhileIworkedonthisbook.


IconsUsedinThisBook
[Viewfullsizeimage]

CommandSyntaxConventions
Theconventionsusedtopresentcommandsyntaxinthisbook
arethesameconventionsusedintheIOSCommandReference.
TheCommandReferencedescribestheseconventionsas
follows:
Boldfaceindicatescommandsandkeywordsthatare
enteredliterallyasshown.Inactualconfigurationexamples
andoutput(notgeneralcommandsyntax),boldface
indicatescommandsthataremanuallyinputbytheuser
(suchasashowcommand).
Italicsindicateargumentsforwhichyousupplyactual


values.

Verticalbars(|)separatealternative,mutuallyexclusive
elements.
Squarebrackets[]indicateoptionalelements.
Braces{}indicatearequiredchoice.
Braceswithinbrackets[{}]indicatearequiredchoice
withinanoptionalelement.


Introduction
Inthefirsteditionofthisbook,whichwascompletedin1999,
therewasastrugglehappeningbetweenthe"new-worldservice
providers"andtheexisting"monolithicprovidersand
corporations."Weallknowtheendingtothisparticularstory.
Mostofthenew-worldcompaniesandserviceproviderswent
outofbusiness,andtheirassetswereliquidatedorconsumed
bythemonolithicserviceproviders.
ThefalloutfromthebubblebursthadanimpactonVoiceover
IP(VoIP)aswell.WasVoIPgoingtobeanadditionalvictimof
thetechnologiesandstartupsthatwereattachedtothenew
wayofdoingbusiness?Youdon'thavetolookintoacrystalball
todeterminetheoutcome.Themarketplacehasdecided.VoIP,
andingeneral,"IPcommunications,"isandwillcontinuetobe
thedefactomechanismforcommunicationsfortheforeseeable
future.
InarecentreportbytheTelecommunicationsIndustry
Association(TIA),residentialVoIPconsumersmorethantripled
in2005.TheTIAalsopredictedacompoundedannualgrowth
rateofmorethan40%through2009.Thiswouldaccountfor
morethan18millionconsumerVoIPconnections.Thisshows
thatpacketvoiceisnotonlygrowingrapidly,itisheretostay.

Thisisjustoneexampleintheconsumerspaceoftheadoption
ofthistechnology.Theadoptioninsmall,midsize,andlarge
businesseshasalsobeentremendous.
LegacyTDMPBXsarebeingreplacedatarapidpacebyfeaturerichenterprisebusinesscommunicationtools.Itisnotjust
aboutacheaperwaytotransmitvoice,butratheranentirely
newwayofcommunicatingwithyourpeersandassociates.
Theoriginalversionofthisbookhashadaratherlongshelflife.
MyoriginalcoauthorJamesPetersandIdesignedthebookto


focusonthebasicfundamentalsthatwouldallowforthistobe
areferenceformanyyears.Althoughthemarketplacemay
changeweektoweekandmonthtomonth,oncethebasic
foundationaltechnologiesareovertheirinitialhypergrowth,
theyusuallylevelofftoasteadytechnicalgrowthdrivenbynew
applications.
TheoriginalVoiceoverIPFundamentalsisadinosaurin
technicalbooklifespan,butmanyofitsoriginaltenetshold
true.Onegoalfortheupdateofthisbookwastorefreshallthe
technologyelementsthathavechangedoverthepastsixyears.
Forexample,SessionInitiationProtocol(SIP)wasjustbeing
finalizedin1999,andyettodayitisthecornerstoneformany
newapplications(mobilephone"pushtotalk"andtheIMS
architecture).Asecondkeygoaloftherefresh,andjustas
important,istodiscussthenewapplicationsforthese
fundamentaltechnologiesandhowtheyimpacttheirusers.


PurposeofThisBook
WhatisVoIPandinwhatwaysdoesitapplytoyou?VoIP

providesthecapabilitytobreakupyourvoiceintosmallpieces
(knownassamples)andplacetheminanIPpacket.Voiceand
datanetworkingontheirownarecomplextechnologies,and
therearemanybookswrittenoneachsubject.Thisbook
explainshowabasictelephonyinfrastructureisbuiltandworks
today,majorconceptsconcerningvoiceanddatanetworking,
transmissionofvoiceoverdata,andIPsignalingprotocolsused
tointerworkwithcurrenttelephonysystems.Italsoanswers
thefollowingkeyquestions:
WhatisIP?
Howisvoicesignaledintelephonenetworkstoday?
WhatarethevariousIPsignalingprotocols,andwhichone
isbestforwhichtypesofnetworks?
Whatisqualityofservice(QoS)andhowdoesoneensure
goodvoicequalityinanetwork?
Inadditiontocoveringtheseconcepts,thisbookalsoexplains
thebasicsofVoIPsothatanetworkadministrator,software
engineer,orsomeonesimplyinterestedinthetechnologyhas
thefoundationofinformationneededtounderstandVoIP
networks.
Thisbookismeanttoaccomplishthefollowinggoals:
Provideanintroductiontothebasicsofenterpriseand
publictelephonynetworking


IntroduceIPnetworkingconcepts
Provideasolidexplanationofhowvoiceistransportedover
IPnetworks
Coverthevariouscaveatsofconvergingvoiceanddata
networks

ProvidedetailedreferenceinformationonvariousPublic
SwitchedTelephoneNetwork(PSTN)andIPsignaling
protocols
Althoughthisbookcontainsplentyoftechnicalinformationand
suggestionsforwaysyoucanbuildaVoIPnetwork,itisnota
designandimplementationguideinthatitdoesn'tprovide
detaileddeploymentinformation.




WhoShouldReadThisBook?
Eventhoughthisbookiswrittenforanyoneseekingto
understandhowtouseIPtotransportvoice,itstargetaudience
comprisesbothvoiceanddatanetworkingexperts.Inthepast,
voiceanddatagurusdidnothavetoknoworunderstandeach
other'sroles.Inthisworldoftime-divisionmultiplexing(TDM)
andIPconvergence,however,itisimportanttounderstandhow
thesetechnologieswork.Thisbookexplainsthedetailssothat
voiceexpertscanbegintounderstanddatanetworking,and
viceversa.
Thebooklayoutgeneratesyetanotheraudience:Thosewho
havelimiteddataandvoicenetworkingknowledgebutare
technicallysavvywillbeabletounderstandthebasicsofboth
voiceanddatanetworkingalongwithhowthetwoconverge.
Despiteitsdiscussionsofvoiceanddatanetworking,thisbook
isreallyaboutVoIP,andtheprotocolsthataffectVoIPare
explainedingreatdetail.Thismakesthisbookareference
guideforthosedesigning,building,deploying,orevenwriting
softwareforVoIPnetworks.

ReadersfamiliarwithIPnetworkingmightwanttoskipChapter
6,"IPTutorial."Similarly,voice-networkingexpertsmightwant
toskipChapter3,"BasicTelephonySignaling."