InterproviderInterprovider IPIP--MPLS InternetworkingMPLS Internetworking

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OutlineOutline

nn DriversDrivers

nn RequirementsRequirements

nn ChallengesChallenges

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Drivers: Target ApplicationsDrivers: Target Applications

nn MPLSMPLS--IPVPN: Extension of IPVPN services to out of IPVPN: Extension of IPVPN services to out of service territoriesservice territories

nn L2 L2 VPNsVPNs and L2 circuits: Extension of L2 VPN and PW and L2 circuits: Extension of L2 VPN and PW services to out of service territories services to out of service territories

nn VoIPVoIP and the new PSTN : and the new PSTN : InterproviderInterprovider VoIPVoIP servicesservices

nn Traffic tunnels: Efficient LongTraffic tunnels: Efficient Long--haul packet transport haul packet transport capacitycapacity

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Drivers: Target ApplicationsDrivers: Target Applications--IPVPN IPVPN

nn IPVPN Services: A typical ScenarioIPVPN Services: A typical Scenario

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Drivers: Target ApplicationsDrivers: Target Applications--IPVPN (cont.)IPVPN (cont.)

nn IPVPN ServicesIPVPN Services–– No single provider has the geographic presence to provide univerNo single provider has the geographic presence to provide universal IPVPN sal IPVPN

services to customers. Provider Options:services to customers. Provider Options:•• Only serve customers that are in the provider’s geographic areasOnly serve customers that are in the provider’s geographic areas

–– Burden of site interconnectivity is on the customer or a third pBurden of site interconnectivity is on the customer or a third party that acts on behalf the arty that acts on behalf the customer. customer.

»» However, service requirements are not limited to connectivity orHowever, service requirements are not limited to connectivity or plumbingplumbing–– Often lead to missed opportunitiesOften lead to missed opportunities

•• Use public facilities to bring the customer to the provider Use public facilities to bring the customer to the provider PoPPoP for IP VPN services. for IP VPN services. Often requires Often requires InterproviderInterprovider connectivity at some layer:connectivity at some layer:

–– Layer1 (TDM): Layer1 (TDM): »» Cost increases as a function of distance Cost increases as a function of distance »» Suboptimal use of bandwidth and dollars: e.g., transport of bestSuboptimal use of bandwidth and dollars: e.g., transport of best effort traffic in long hauleffort traffic in long haul

–– Layer 2 (ATM/FR/Ethernet VCs): Layer 2 (ATM/FR/Ethernet VCs): »» Cost increases as a function of distance and QoSCost increases as a function of distance and QoS»» Tradeoff between connection complexity, QoS and costTradeoff between connection complexity, QoS and cost

–– IP over the public Internet: Provider loses control of QoS and aIP over the public Internet: Provider loses control of QoS and availability. In other words vailability. In other words lose valuelose value

–– May be cost prohibitive or performance prohibitive: e.g., a US cMay be cost prohibitive or performance prohibitive: e.g., a US carrier serving customers arrier serving customers with international locationswith international locations

•• Work with other providers to costWork with other providers to cost--effectively extend IPVPN service reach effectively extend IPVPN service reach –– Route close to customer sitesRoute close to customer sites–– Create opportunities or competitive threat? Where is the value?Create opportunities or competitive threat? Where is the value?

–– IPIP--MPLS MPLS InterproviderInterprovider Internetworking is necessary to provide costInternetworking is necessary to provide cost--effective effective IPVPN services across many providers’ IPVPN services across many providers’ terrirotoriesterrirotories

•• Still need to define what internetworking meansStill need to define what internetworking means

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Drivers: Target ApplicationsDrivers: Target Applications--L2VPNs/PWs L2VPNs/PWs

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Drivers: Target ApplicationsDrivers: Target Applications--L2VPNs/PWs (cont.) L2VPNs/PWs (cont.)

nn L2 L2 VPNsVPNs::–– Provide customer siteProvide customer site--toto--site L2 (ATM/FR/Ethernet) connectivity. site L2 (ATM/FR/Ethernet) connectivity. –– Most prominent moneyMost prominent money--making data service todaymaking data service today–– Some think that they will not be fully replaced (for various reaSome think that they will not be fully replaced (for various reasons) sons)

by IPVPNs although conversion is happeningby IPVPNs although conversion is happening

nn InterproviderInterprovider L2 VPN/L2 VPN/PWsPWs over IPover IP--MPLS driversMPLS drivers–– IntraIntra--carrier carrier multiservicemultiservice convergence over IPconvergence over IP--MPLS networks will MPLS networks will

naturally lead to naturally lead to multiservicemultiservice convergence over the interconnect convergence over the interconnect •• Usefulness of the network/interconnect increases with usageUsefulness of the network/interconnect increases with usage•• InterproviderInterprovider ATM/FR circuits are common today and driven by ATM/FR circuits are common today and driven by

coverage:coverage:–– IntraIntra--carrier segments being increasingly carried over IPcarrier segments being increasingly carried over IP--MPLSMPLS–– Extend the IPExtend the IP--MPLS transport across the interconnectMPLS transport across the interconnect

•• Extension of evolving Ethernet virtual pseudo wire services and Extension of evolving Ethernet virtual pseudo wire services and Virtual Virtual Private LAN services across carrier boundaries to increase coverPrivate LAN services across carrier boundaries to increase coverageage

•• May be used to backhaul L2 Circuits for access to a provider IPMay be used to backhaul L2 Circuits for access to a provider IP--VPN VPN POP for IPVPN servicesPOP for IPVPN services

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Drivers: Target ApplicationsDrivers: Target Applications--VoIPVoIP

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Drivers: Target ApplicationsDrivers: Target Applications--VoIPVoIP (cont.)(cont.)

nn VoIPVoIP::–– Enterprise Enterprise VoIPVoIP transport (not network service) by providerstransport (not network service) by providers

•• Enterprises increasingly using Enterprises increasingly using VoIPVoIP for for intersiteintersite voice voice communicationscommunications

–– Transport mechanism among sites: IPVPNs or L2VPNsTransport mechanism among sites: IPVPNs or L2VPNs

–– Network Network VoIPVoIP services by providers: The new PSTNservices by providers: The new PSTN•• Today, carrier voice infrastructures are being migrated to Today, carrier voice infrastructures are being migrated to VoIPVoIP•• Next step, Next step, IntercarrierIntercarrier VoIPVoIP

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Drivers: Target ApplicationsDrivers: Target Applications--Traffic Tunnels Traffic Tunnels

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Services and Requirements From a Provider EyeServices and Requirements From a Provider Eye

nn InterproviderInterprovider IPVPNIPVPN–– Preservation of customer IPVPN privacy and connectivityPreservation of customer IPVPN privacy and connectivity–– Consistency of network services provided to the customer: Consistency of network services provided to the customer:

•• Customer gets same network services wherever he/she is connectedCustomer gets same network services wherever he/she is connected–– Ability to run the same applications between any two sitesAbility to run the same applications between any two sites

»» intermediate provider networks must satisfy application QoS requintermediate provider networks must satisfy application QoS requirements irements »» An approach is to categorize applications in terms of traffic clAn approach is to categorize applications in terms of traffic classes (e.g., voice, video, priority data asses (e.g., voice, video, priority data

and best effort services): An accepted approach todayand best effort services): An accepted approach today»» Customer cares about he/she gets and not how it is done albeit hCustomer cares about he/she gets and not how it is done albeit he/she needs to be convinced that e/she needs to be convinced that

it can be doneit can be done

–– Preservation of customerPreservation of customer--internal internal CoSCoS marking sitemarking site--toto--site and therefore across the site and therefore across the interconnectinterconnect

»» Provider ability to differentiate between markings needed for trProvider ability to differentiate between markings needed for transport and customer markingsansport and customer markings

–– Common edge policies on customer traffic treatmentCommon edge policies on customer traffic treatment

–– IPVPN availabilityIPVPN availability•• Integral part of any SLA Integral part of any SLA •• Impacted by many factors Impacted by many factors

–– one of the factors is network resiliency and fast reroute arounone of the factors is network resiliency and fast reroute around failuresd failures•• Ideally, must not be impacted by the presence of multiple intermIdeally, must not be impacted by the presence of multiple intermediate providersediate providers

–– Definition of Performance metricsDefinition of Performance metrics•• What they areWhat they are•• What their targets areWhat their targets are•• How to measure them and present them to the customer when multipHow to measure them and present them to the customer when multiple provider le provider

networks are transporting traffic between two customer sitesnetworks are transporting traffic between two customer sites

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Services and Requirements From a Provider Eye Services and Requirements From a Provider Eye (cont.)(cont.)

nn L2VPNs and L2 L2VPNs and L2 VPWSsVPWSs–– Ability to preserve the QoS/Bandwidth requirements of the L2 Ability to preserve the QoS/Bandwidth requirements of the L2

services as the services cross two or more provider IPservices as the services cross two or more provider IP--MPLS networksMPLS networks–– Transparency to customerTransparency to customer–– Availability/ResiliencyAvailability/Resiliency

•• Need to define methods to provide for Need to define methods to provide for interproviderinterprovider L2VPN and VPWS L2VPN and VPWS resiliency to reroute around failure pointsresiliency to reroute around failure points

–– Performance MetricsPerformance Metrics

nn VoIPVoIP: The new PSTN: The new PSTN–– Expectations are very high for QoS and availability as it attempExpectations are very high for QoS and availability as it attempts to ts to

replace the existing PSTN replace the existing PSTN –– HighHigh--level QoS for control and RTP streams with low delay, low jitterlevel QoS for control and RTP streams with low delay, low jitter

and very low packet lossand very low packet loss–– High availability and resiliency to network failuresHigh availability and resiliency to network failures

nn TrafiicTrafiic tunnelstunnels–– Bandwidth/QoS guaranteesBandwidth/QoS guarantees–– Resiliency to network failuresResiliency to network failures

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ChallengesChallenges

nn No standard way of building IPNo standard way of building IP--MPLS interconnects that satisfy all applications MPLS interconnects that satisfy all applications and their requirementsand their requirements

–– Even for IPVPN, there are many ways to build an Even for IPVPN, there are many ways to build an interproviderinterprovider VPNVPN–– The networking methodology has implications on how The networking methodology has implications on how CoSCoS is relayed across the is relayed across the

interconnect without losing specificity of the individual custominterconnect without losing specificity of the individual customer edgeer edge--connectionsconnections

nn No standard definition of services (traffic classesNo standard definition of services (traffic classes--meaning and behavior)meaning and behavior)–– Providers independently define services (traffic classes, servicProviders independently define services (traffic classes, service level targets, customer e level targets, customer

profiles) as they may target different applicationsprofiles) as they may target different applications–– Requires definition of service and DSCP/exp mappings across domaRequires definition of service and DSCP/exp mappings across domain boundaries in boundaries –– No standard way of defining policies to be applied to customersNo standard way of defining policies to be applied to customers

•• Each carrier defines its own Each carrier defines its own àà changes impact changes impact OSSsOSSs and/or overall service definitionsand/or overall service definitions–– Challenge to providing consistent network services to customersChallenge to providing consistent network services to customers

nn No agreedNo agreed--on mechanisms for network troubleon mechanisms for network trouble--shooting across providersshooting across providers–– HumanHuman Interaction across providers Interaction across providers àà delay in problem resolutiondelay in problem resolution

nn No standard mechanism for No standard mechanism for intercarrierintercarrier OAMOAM

nn No standard mechanisms for fast reroute around failures across dNo standard mechanisms for fast reroute around failures across domain omain boundariesboundaries

–– Depend on the interconnect methodDepend on the interconnect method

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Challenges (cont.)Challenges (cont.)

nn No standard definition for performance metrics, metric measuremeNo standard definition for performance metrics, metric measurements and nts and targetstargets

–– Each provider defines its own Each provider defines its own –– No standard way of presenting performance data for customer trafNo standard way of presenting performance data for customer traffic that crosses two fic that crosses two

or more providersor more providers–– Challenge the definition of SLAs when Challenge the definition of SLAs when multiprovidersmultiproviders are involved in the data path of are involved in the data path of

customer trafficcustomer traffic

nn Traffic policing/shaping per class at domain boundariesTraffic policing/shaping per class at domain boundaries–– Needed to protect domain Needed to protect domain –– But you can potentially impact customer traffic as the interconnBut you can potentially impact customer traffic as the interconnect is an aggregate ect is an aggregate

point. This can be more important to the party that owns the cuspoint. This can be more important to the party that owns the customertomer–– Should it be done? Should it be done per customer? Or should youShould it be done? Should it be done per customer? Or should you treat the treat the intercarrierintercarrier

link as a core link or as an aggregate link as a core link or as an aggregate intercarrierintercarrier links? links? –– Implications on interconnect methodImplications on interconnect method

nn How to How to statisfystatisfy the various target network services across carrier interconnectthe various target network services across carrier interconnect

nn InterdomainInterdomain security considerationssecurity considerations

nn Vendor Interoperability as different carriers are likely to haveVendor Interoperability as different carriers are likely to have different preferred different preferred vendors (problem also within a carrier network with multiple venvendors (problem also within a carrier network with multiple vendor equipment)dor equipment)

nn Billing, accounting and settlements Billing, accounting and settlements

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Challenges (cont.)Challenges (cont.)

nn Customer CareCustomer Care–– Who owns the customer: Who owns the customer:

•• Take order of new connectionsTake order of new connections•• Point of contact for problem resolutionPoint of contact for problem resolution

–– Who defines the service to the customer and impact as Who defines the service to the customer and impact as incremental need arises to work with more carriers to provide thincremental need arises to work with more carriers to provide the e same customer with additional connectionssame customer with additional connections

nn Most interconnections today are negotiated on a bilateral basis Most interconnections today are negotiated on a bilateral basis as no two carriers are the same as no two carriers are the same –– Big effort as number of carriers you peer with increasesBig effort as number of carriers you peer with increases

•• Effort increases as the number of network services you need to sEffort increases as the number of network services you need to support upport increases increases

•• The more the issues that you need to define and address are the The more the issues that you need to define and address are the bigger bigger effort iseffort is

–– This process will not be eliminated but This process will not be eliminated but •• how much of it can be simplified/reduced by standardization and how much of it can be simplified/reduced by standardization and

probably developing Best Common Practicesprobably developing Best Common Practices•• ForaFora and standard bodies need to complement each others to help and standard bodies need to complement each others to help

reduce the challenges and simplify the processreduce the challenges and simplify the process