white paper flexi ng versus routers

7/31/2019 White Paper Flexi Ng Versus Routers

1/16

Meeting the demands of converged networks:

Routers or purpose-built gateways?

White Paper


2/16

2 Routers or purpose-built gateways white paper

Executive summary:Choosing routers or gateways for converged networks

For many years fixed and mobilecommunications infrastructure haveevolved along different paths, being

based and developed on differentsystem architectures and optimized tomeet different communications needs.

The delivery of Internet servicesthat are independent of device andlocation, and the high maintenancecosts to run separate networks areencouraging fixed and mobile networkcommunications service providers(CSP) to consider the convergenceof their networks.

This raises the question about whicharchitecture approach, fixed or mobile,is better suited to the need of futurenetworks. In short is it better toimplement routers with built-in mobilegateway functionality, or to deploynetwork gateways with built-in router functions?

Future growth opportunities areplentiful on the mobile side. Oneresearch firm predicts that mobilebroadband subscriptions will exceed

1 billion during 2011. Such growth isbeing driven by the availability of high-speed wireless connectivity,great consumer devices deliveringexcellent customer experience, andthe rapidly growing popularity of socialnetworking.

The characteristics of mobilecommunications impose technicaldemands that are not seen in fixednetworks. For example, the rapid riseof smartphones is creating large

volumes of network signaling trafficthat generate no revenue for the CSPyet must be handled efficiently in order to avoid congestion that can damageservice availability.

This essential difference betweenfixed and mobile traffic characteristicsleads to multi-dimensional scaling

requirements. There are four keydimensions of mobile networks thateither routers or gateways mustaccommodate - high throughputcapacity, high signaling capacity, highsession density and integrated serviceintelligence. Inability to provide highperformance, scalability and flexibilityin all four dimensions can lead to apoor customer experience and restrictCSP business growth.

It turns out that routers are largely

unable to manage the combination of data and signaling traffic that mobilenetworks create, whereas purpose-built mobile gateways based on open,standards-based hardware platformscan not only support key routingcapabilities, but are also able to meetthe requirements of existing and futuremobile packet core networks.

The Nokia Siemens Networks FlexiNetwork Gateway uses a uniquedesign based on the open ATCA

platform that achieves lower cost,higher performance and better flexibility than a router-based platform.

When comparing routers and purpose-built gateways in terms of cost andthroughput, some CSPs concludeerroneously that purpose-builtgateways are relatively expensive.Yet its the benefits of ATCA (fast timeto market, commercially availablecomponents, latest innovations tokeep pace with Moores law describing

the long-term trend in the history of computing hardware) that makepurpose-built mobile gatewaysultimately more efficient than fixedrouter-based solutions.

Table of contents

2 Executive summary: Choosingrouters or gateways for convergednetworks

3 Growing digital lifestyle puts newdemands on the mobile packet core

5 Mobile broadband raises newchallenges

8 Gateways with router functionality or routers with gateway functionality?

11 The value of open, standards-basedhardware platforms

12 Nokia Siemens NetworksFlexi Network Gateway

14 Conclusion: Gateways outperformrouters in converged networks

15 Abbreviations

2


3/16

3Routers or purpose-built gateways white paper

Growing digital lifestyle puts new demandson the mobile packet core

The booming digital lifestyle iscreating unprecedented change in thecommunications sector. It could be

argued that the scale of change over the last five years has been greater than in the preceding 100 years. Inlittle more than five years, for example,Facebook has grown from launchto claim 500 million users by theend of 2010, helping to make socialnetworking the fourth most popular online activity globally.

The rate of change shows no signs of slowing. It is likely that by 2015, mobiledata traffic will have increased by far

more than 1,000 percent, reaching23 Exabytes per year, equivalent to6.3 billion people each downloading a

digital book or 2-3 music files everyday. There are already 500 millionsmartphone or tablet computer users.In five years, there are likely to be twobillion.

Mobile technologies will dominatethe growth in the number of peopleconnected over the next five years. In2010, out of a total world population of

just under 7 billion, 3.1 billion peoplehad mobile access, with 600 millionusing fixed connections. By 2015 the

number of fixed connections willremain flat while 4.4 billion peoplewill have mobile connectivity.

It is not just applications like socialnetworking that are driving this extremegrowth.

The sheer number and variety of devices, particularly smart devices,being connected is booming too.Communications networks will needto deal with a huge number of homedevices like desktops, machines, smartovens, electricity meters, 3D HDTV, settop boxes, and video gaming consoles.

Figure 1: Internet market growth

Source: Combined analyst data and NSN AnalysisHarbor research Pervasive Internet & Smart Services Market Forecast

0%

200%

400%

600%

800%

1000%

1200%

2009 20150 bn$

500 bn$

1.000 bn$

1.500 bn$

2.000 bn$

2.500 bn$

3.000 bn$

Voice

Data

Dataapps

Adjacentindustry

Traffic growthof 50% YoY

Objectsgrowth of 40% YoY

Subscriber growthof 10% YoY

3


4/16


Meanwhile, we are seeing huge growthin the number of mobile Internetdevices such as laptops, netbooks,

tablets, eBook readers, smartphones,MP3 players, digital cameras, portablenavigation devices, connected cars,and body sensors.

Many of these devices and their applications depend upon the deliveryof real-time content to and from thecloud. There is growing demand for high definition (HD) video conferencing,

HD audio streaming, 3D HDTVstreaming, video sharing, mobilepayment, remote office working, home

automation, smart grid control,security, and remote health monitoring.

A third driver of growth is the rise of individualization and communities.Professional communities and socialnetworking are creating demand for shared information and sharedlocation. In addition, content andapplications are being tailored to

users or groups of users needs, suchas advertisements, entertainment andconnected objects.

Such is the pace of development thattechnologies and applications arebreaking out of the classicaltelecommunications market and beingadopted by vertical markets such asenergy, building, retail, healthcare,transport and security.

Figure 2: Smart services market growth

0 bn

10 bn

20 bn

30 bn

40 bn

50 bn

60 bn

R e v e n u e p e r y e a r

Healthcare

Retail Energy Transport Security Industrial IT &networks

Building

27%

25% 34%

33%

34% 40% 29%

35%

2 0 1 1

2 0 1 0

2 0 1 2

2 0 1 3

70 bn

80 bn

280 bn market in 2013 with an average growth rate of 33% (CAGR)

Source: Harbor Research Pervasive Internet & Smart Services Market Forecast (2010-2013)

4


5/16


Mobile Broadband growth is a globalphenomenon being driven by thedramatic evolution of terminals, rapid

growth of laptop data cards andwidespread deployment of high speednetworking technologies.

People rely on their smart devicesto help them make decisionslarge and small instant information,instant peer advice, and onlinerecommendations are increasinglyinfluencing what people do every day.Today, more than 150 million active

users access Facebook through their mobile devices and these mobile usersare twice as active as non-mobile

users.

In developed countries, users expectsimilar performance as fixed broadbandand mobile voice. In growth markets,mobile broadband through basichandsets is the first and only access tothe Internet for many people. Predictingand modeling mobile broadband trafficis more complex than mobile voice or text messaging ever has been.

Nearly 1 Exabyte (EB is a number with18 digits) of IP traffic was sent over mobile devices and networks during

2008. That figure will rise dramaticallyin the next few years. Several regionsof the world will then be transferringmore mobile data per month than theyare today.

Mobile broadband raises new challenges

Figure 3: Total mobile network data traffic from 2008 to 2014

Source: ABI Research, 3Q2009 Mobile Data Traffic Analysis

0

5

10

15

20

2008 2009 2010 2011 2012 2013 2014

M o

b i l e

d a

t a t r a

f f i c i n E x a

b y

t e s

AfricaMiddle EastLatin AmericaNorth America

Asia-PacificEastern EuropeWestern Europe

5


6/16


becoming a killer application for router-based gateways. In manydeveloped markets smartphone

penetration is more than 20% andgrowing rapidly with new shipmentsrising at up to 80% per year.

The four dimensions of network demand

There are four key aspects, or dimensions, of mobile broadband thatmobile packet core platforms andproducts must tackle:

High Throughput Capacity: Coupled with flat mobile datatariffs, new mobile devices andradio access technologies haveencouraged consumers to viewmobile broadband as a viablealternative to fixed broadband.Consequently, mobile Internetuse via handsets tripled in2010, creating more and moredata traffic that networks musthave the capacity to be ableto handle.

Yet thats not the whole story becausewe also need to consider the typesof traffic being generated by mobile

devices. Laptops tend to create justhigh volumes of data traffic. But,smartphones generate high volumesof signaling traffic, which can peakunexpectedly and cause poor network performance when a newapplication gains in popularity or anew smartphone operating system isreleased for instance.

An average laptop with a data cardconsumes up to six times more trafficthan the most active smartphone

currently. But a smartphone is alwayson and produces a lot of signalingtraffic as it disconnects and reconnectsto the network while looking for updated content. This constantsignaling creates no revenue for the CSP but can create networkcongestion, poor handset battery lifeand slow online response.

In the future, mobile networks willhave to deal with all the traditionalmobile devices, but smartphones are

High Signaling Capacity: The increasing popularity of smartphones with interactive

applications that connect to theInternet frequently has created aleap in the volume of signalingtraffic in the mobile gateway.

In addition, mobile networks seemany more transactions than fixednetworks. Sessions (or bearers) arecreated, modified and disconnectedas mobile subscribers are switchedbetween base stations and/or SGSNs and as devices movebetween different radio access

technologies, for example from LTEto 3G and vice versa.

Figure 4: Broadband wireless subscriptions from 2008 to 2014

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

2008 2009 2010 2011 2012 2013 2014

M o

b i l e

d e v

i c e s

i n m

i l l i o n s

C ons ume r d ata card s E nte rp ris e data card s S martp ho ne s Mob ile d evic es in us e

Source: Yankee Group Research, Sep 2010 Link Data Global ConnectedView Forecast

6


7/16


This tearing down of radio accessbearers creates many packetdata protocol (PDP) context

modifications with Direct Tunnel, inwhich RNCs are connected directlyto the gateway, bypassing theSGSN. I-HSPA even removesRNCs altogether, a 3GPP flatarchitecture that is also used in LTE(see Figure 5).

Moreover, LTE will significantlyincrease signaling load, because allsubscriber movements are directlyvisible to the gateway. User profilesare also often accessed and

changes reported back to policycontrol and charging systems in thecore network.

High Session Density: Moresubscriptions, always-onconnectivity, and an increasingnumber of applications (dongles,M2M, IM and push email) aredriving high session density. Theadvent of smartphones with multipleapplications running creates notonly high levels of data traffic, but

multiple sessions (or bearers) per

subscriber/terminal. LTE is always-on with default bearers for everyconnected device. Additionally,

multiple dedicated bearers per subscriber for services with differentQuality of Service (QoS) further increase the number of sessions.

Service Intelligence: Typically, just5% of subscribers consume morethan 90% of network capacity. Bydifferentiating services and applyingdifferent QoS to different services,CSPs can make the most efficientuse of limited capacity and optimizetheir network resources. This enables

them to avoid network congestionand build customer loyalty byensuring a superior customer experience on all mobile devices.

With network-based intelligence,CSPs can offer different services todifferent subscriber classes, enforcefair usage limits, enable differentcharging for premium servicesbased on content or by using DeepPacket Inspection (DPI), and collectstatistics about subscriber behavior

to optimize customer care.

All four dimensions require theability to provide high performance,scalability and flexibility in order not to

endanger the customer experienceand restrict CSP business growth. Aproper balance across all dimensionsis needed to maintain systemperformance.

Network evolution towards flatter architecture is very important toconsider. The replacement of BSCs andRNCs by LTE Base Stations means thatthe MME and S/P-GW will face higher demand for mobility management andsignaling load, and many more network

elements that need to be interfaced.

Figure 5: The evolution of traditional Packet Core to Evolved Packet Core (EPC)

Evolved Packet Core

2G

BSC

RNC

Radio access network

eNodeB

IMS

Services in packetdata network

Internet

Operator services

Company intranets

PCRFHLR/HSS AAA Charging

3G

User plane

Control plane

BTS

NodeB

MME

SGSN

S-GW P-GWLTE

7


8/16


Fixed networks have typically beenbuilt using access multiplexers (e.g.DSL Access Multiplexers (DSLAM)) to

connect subscribers and broadbandaggregation nodes to concentrateuser traffic. The BRAS/BNG terminatesthe connections and authenticatessubscribers, assigns IP addresses androutes data traffic to and from theInternet and other corporate servicesor data services.

In mobile networks, subscribers accessdata services by connecting via variousradio access technologies (2G, 3G, andLTE) to the mobile packet-switched

core and to the mobile circuit-switchedcore domain for telephony. The ServingGPRS Support Node (SGSN) or server handles subscriber authenticationand mobility management, while theGateway GPRS Support Node (GGSN)or gateway terminates the packet dataconnections from the user device,handles IP address allocation, routesand forwards IP packets, and performspolicy and charging functions.

However, the rising use of Internet

services across a wide range of devices independent of whether peopleare stationary at home or are traveling,and the high cost of running separatenetworks are encouraging fixed andmobile CSPs to consider theconvergence of their networks.

This raises the question of whichapproach to network design is better suited for future networks - gatewaysor routers? Is it better to deploy routerswith built-in gateway functionality or

gateways with built-in router capabilities?

How routers and gatewaysdiffer

In general, routers have beendeveloped for high capacity packetforwarding in fixed networks and arebuilt on the basic design principle of aclear separation between control plane(routing engine) and forwarding plane(packet forwarding engine) to achievehigh resiliency and reliability.

Routers offer powerful packetforwarding with high-performance IP/MPLS lookup and are optimized for wireline speed any-to-any forwarding.

They are robust and implementcomprehensive protocol support for routing and transport and provide awide range of different interfaces fromlow bit rate to ultra-high capacity (PDH,SDH/ATM, 100 Gigabit Ethernet).BNGs have developed from fixedbroadband termination, wherebandwidth is the main factor withtypically very little state information(for example no mobility), simplecharging, and limited use of controlinterfaces.

In contrast, purpose-built mobilegateways must fulfill various other functions, besides forwarding packetsand routing between the Gn (interfacebetween SGSN and GGSN) and Gi(interface to PDN, e.g. Internet).

Mobile networks pose additionalrequirements, including managingsubscribers and their sessions inconjunction with mobility. Securityand redundancy must also be

handled at the subscriber and/or session level.

Routers separate the controlplane and user plane

As mentioned above, a key architecturalaspect of routers is that they decouplethe user plane (UP) from the controlplane (CP). While this works well for

routing and forwarding, it is not the idealarrangement for mobile gateways.

Current router-based GGSNs terminatethe GPRS Tunneling Protocol (GTP) onan application blade, which means thatall traffic is forwarded internally to ageneral purpose CPU. The centralizedcontrol plane creates transactionsbetween the routing engine and thepacket forwarding engine to handlesignaling, which reduces the routersoverall switching capacity and may

cause bottlenecks between separatecards.

Gateways with router functionality or routers with gateway functionality?

Is the market moving togateways?

A few years ago, a major router vendor introduced apurpose-built mobile gatewayinto its portfolio by acquiringa small company. In October 2009, Current Analysis said:The acquisition is essentiallya tacit acknowledgement thatrouters are not the best fit for all network applications you cannot develop everyspecialized network application

on a router and get whatoperators need.

8


9/16


typically run fewer sessions due to theabsence of subscriber mobility. Also,subscriber management and policy

handling have not been a prioritybecause very little state information isneeded in fixed broadband networks.

Session scalability in routers is limitedby their use of ASICs and depends onthe memory architecture (TCAM) whichcan lead to swapping of sessions dueto limited memory. The separated UPand CP architecture requires twice asmuch memory footprint.

A purpose-built gateway, on the other

hand, can use standard memory likeSynchronous Dynamic RAM (SDRAM),enabling faster evolution and providingsignificantly greater capacity for sharedsubscriber session handling.

The impact of different packetflows

Incorporating a mobile gateway with arouter-based platform relies on therouters separate mobility/services

engine and forwarding engine to handleCP and UP traffic respectively. Themobility/services engine typically usesgeneral purpose processors to managethe CP, while the forwarding engine hascustom ASICs to handle UP traffic. Thiscan lead to bottlenecks, as CPtransactions need to be communicatedacross blades.

In contrast, a purpose-built gatewaybased on flexible ATCA architecturecan use a single blade to handle both

UP and CP traffic, enabling the use of shared RAM for extremely efficientoperation. UP and CP performancecan be handled flexibly within theblades and is software-configurable.

Traffic handling and QoS for each bearer requires

substantial memory

Routers are typically very powerful, butdo not provide enough memory tohandle the high number of sessionswith state information that are seenat the GGSN and which will evenincrease with the introduction of flatall-IP networks and the advent of LTE.

High subscriber and session densityrequire a large number of queuesand corresponding policers/shapers

per session (or bearer) to limit thebandwidth and implement subscriber and service individual quality of service.

Unlike fixed networks in which eachsubscriber has a dedicated bit rateand access (DSL for instance), mobilenetworks suffer from scarce radioresources, which are also sharedamong several subscribers in a radiocell. To ensure fair usage for allsubscribers, bandwidth may need to be

modified during a session using policyenforcement.

Routers use Application SpecificIntegrated Circuits (ASIC), but evenprogrammable ASICs cannot provideenough queues for the high number of subscribers and sessions. Furthermore,the development of new ASICs iscostly, requiring a sizeable market to

justify the necessary investment, andlengthy, which may not be able to takeaccount of new items developed by

3GPP standardization.

In contrast, purpose-built gatewaysusing software-configurablesolutions based on flexible hardware

(see section The value of open,standards-based hardware platformson page 11) can incorporate changes

quickly. For example, the addition of new user plane (UP) counters is trivialcompared to an ASIC-based solution.

Substantial memory is needed in amobile gateway application to handlethe high density of subscribers andtheir sessions. A typical approach for router design is to use Ternary Content

Addressable Memory (TCAM), that cando a very wide data search in a veryshort, fixed time period to implementlongest prefix match operation for

routing lookup and packet classification.But this kind of technology is expensiveand provides less capacity in thesystem or on a specific blade.

Routers with separated UP and CPdemand even more memory becauseaccess to the subscriber session profileis required for both UP and CP for instance, and because high densityrequires fast access to simultaneouslyhandle the traffic of multiplesubscribers. Even worse, if UP and

CP separation happens on dedicatedboards, then additional processingis needed to keep session profilessynchronized across different blades.

Mobile networks create manymore sessions than fixednetworks

Flat all-IP networks and always-onsmart services (for example electricitymetering) create a huge number of

sessions that need to be supported inthe gateway. Classical routers are notbuilt to manage high numbers of sessions because they have beendeveloped for fixed networks that

9


10/16


charging. Conventionally this is not anissue for fixed networks. The mobilegateway is well placed to report serviceusage to the Policy and ChargingRules Function (PCRF), which thenmodifies session QoS or activatesdifferent policy rules (for instancethrottling).

Policy Charging and Control (PCC)requires substantial flow processingflexibility. A routers ASIC-basedprocessors cannot handle dynamicPCC filters. Furthermore, ASIC-based

In addition, signaling performance canbe scaled up linearly just by addingmore service blades.

Meeting CSPs need for asmart bit-pipe

Mobile networks typically havescarce radio resources that mobileCSPs must manage efficiently byimplementing packet metering for bandwidth management and by usingsophisticated policy enforcement and

UP has limited memory for PCC rulehandling. In addition, charging,especially online charging, requiresconsiderable interaction between theUP and the CP. The decoupledarchitecture of routers is difficult toscale up to meet this requirement.

To summarize, the following key driversdifferentiate the ATCA platform-based,purpose-built mobile gateway frommobile gateways built on top of aclassic router-based platform:

Figure 6: Comparison of packet flow

Flexi Network Gateway ATCA architecture

Mobile gateway on top of a router

Typicaltraffic flow

Flow withL7 DPI

Optimumtraffic flow

Traffic flow for non-optimum case

Serviceblade

Serviceawareblade

Mobility &servicesengine

Routingengine

Forwardingengine

User plane DPI analysisControl plane

Serviceblade

Routingengine

Forwardingengine

Single blade type for user plane (UP) and control plane (CP) Both processed on the same blade (UP processing up to L4). UP and CP performance handled flexibly within the blade. Flows requiring L7 analysis (DPI) switched to another blade

(same hardware).

Decoupled user plane (UP) and control plane (CP) Separated routing engine / mobility & services engine (CP) and

forwarding engine (UP). In optimum scenario, UP only goes via forwarding engine. In other

scenarios, UP needs to be taken to mobility & services engine. L7 Deep Packet Inspection (DPI) on separate blade.

Flexi Network Gateway Routers

Supports key routing capabilities like VRF, IP/MPLS, and BGP.

Support various routing protocols and manytypes of interfaces.

Focuses simultaneously on throughput,signaling, sessions, and service intelligence. Are strong in line rate forwarding, but only withIP/MPLS lookup.

Provides huge memory on board for closeinteraction of user plane and control plane.

Have low memory consumption and pay highpenalty if packets need to be processed ondedicated application hardware.

Benefits from software-based solution for flexiblefeature implementation and from fast hardwareevolution.

Cannot be utilized fully (unused capacity) if usedfor mobile gateway due to bottlenecks.

Gains from ATCA ecosystem (open standard andoff the self).

Use proprietary hardware, making them costlyand inflexible.

10


11/16


Routers on the market today tendto use proprietary chipsets in theform of ASICs, which leads to longer

development cycles and generallyhigher costs because of limitedeconomies of scale.

A more cost-effective approachadopted by Nokia Siemens Networksis to base hardware on AdvancedTelecommunications Computing

Architecture (ATCA) technology asthe strategic common platform for itsgateway and many other core products.

ATCA is an industry specificationcreated by the PCI Industrial Computer

Manufacturers Group (PICMG) thatdefines open standards-basedguidelines for the design and

manufacture of next-generation carrier-grade communication equipment.

Using commercial off-the-shelf (COTS)components that are available frommultiple vendors around the worldreduces the cost of hardware and helpsto achieve fast time to market for thelatest technology industry-wide. ATCA-based hardware is also easily scalableto meet demand and can be designedinto different form factors for moreflexible deployment in a CSP network.

Unlike routers based on ASICs,gateways using standard multi-corepacket processors (MPP) are more

flexible in adapting to changing trafficprofiles and provide dedicated hardwaresupport to accelerate TCP/IP packetdata processing. MPP technology ismodular, highly flexible and scalable,and enables fast development cyclesfor new functionality. The MPP conceptallows full software programmabilityand enables interface capacity to beexpanded easily to meet future networkgrowth.

Control Plane scalability is equally as

important in the mobile environment asUser Plane scalability because of highsignaling loads. The Nokia SiemensNetworks Flexi Network Gatewayimplements service blades with severalmulti-core MPPs and plenty of SDRAMmemory to handle user plane andcontrol plane traffic on the sameboard in a very fast and flexible way.This achieves independent and linear scalability for both planes, as wellas flexibility to modify UP and CPresource allocation by software

configuration on the fly.

Figure 7: Flexible configuration for user and control plane

The value of open, standards-basedhardware platforms

UPCP

Signaling-intensiveconfiguration

ConfigurationOptimization

UPCP

Throughput-intensiveconfiguration

11


12/16


Nokia Siemens NetworksFlexi Network Gateway

The Nokia Siemens Networks FlexiNetwork Gateway is a purpose-built,carrier-class gateway to meet the

needs of all mobile broadbandnetworks. It can be deployed as anintelligent, high-capacity GGSN for HSPA and I-HSPA networks, and at thesame time as an enhanced 3GPP R8Serving and PDN gateway for LTE with

built-in policy and charging functions inthe same rack.

Flexi Network Gateway offers leadingperformance for mobile packet corenetworks making it about twice aspowerful as other gateways on themarket. Its unique design fullyeliminates inter-board communication,

and thus avoids the internal systembottlenecks that routers can suffer.

Flexi Network Gateway provides highlyefficient scaling in all four dimensions of mobile broadband networks asdescribed in section Mobile broadbandraises new challenges on page 5.

Figure 8: Flexi Network Gateway product family

High Throughput Capacity: Flexi Network Gateway provides the highest mobile data throughput capacity on themarket. Within a fully equipped rack, it can provide 360 Gbps (based on 512 Bytes packet size).

High Signaling Capacity: Flexi Network Gateway is highly and linearly scalable, and a three-shelf ATCA platformis able to handle 108,000 signaling transactions per second.

High Session Density: Flexi Network Gateway in a full rack configuration can handle 21.6 million sessions (PDPcontexts or EPS bearers).

Integrated Service Intelligence: Flexi Network Gateway design is flexible and scalable, allowing the serviceintelligence functionality to be predictable. Deep Packet Inspection (DPI) software can be updated and run withoutany interruption of the gateway functionality. It can identify more than 600 different protocols (for example multiplekinds of P2P traffic), representing the vast majority of applications and Internet protocols used today. Leadingservice intelligence on flexible and scalable hardware helps to ensure a superior end user experience andoptimization of network resources.

Next-generation hardware and software platform

DPI DifferentiatedCharging

PolicyEnforcement

Security SecurityReporting

GGSN

2G, 3G

S-GW

2G, 3G, LTE

P-GW

2G, 3G, LTE

Stand-alone L2

2G, 3G, LTE, DSL,WiMAX, CDMA, etc.

BNG

DSL

Flexi Network Gateway product family provides multiple applications based on a commonhardware & software platform, as well as versatile common value adding features on top.

12


13/16


To help CSPs to stay in control of their network, Flexi Network Gatewayprovides Integrated Operationand Maintenance capabilities for configuration management, faultmanagement, and performancemanagement. A mobile gatewayapplication is often a loose hardwareintegration, a box hosting several

independent gateways (GGSN for 2G/3G and S/P-GW for LTE) andDPI nodes. Flexi Network Gatewayenables a CSP to log in on every cardseparately.

Figure 9: Unique 4D scaling makes Flexi Network Gateway the most powerful gateway

Leading service intelligenceto ensure user experiencewhile optimizing network

Leading session density for always-on subscribers21.6 m and 36 m in 2012

MME

S/P-GW

Leading signaling capacity for Smartphone traffic in LTE108 k tr/s and 324 k tr/s in 2012

Leading throughput toaccommodate traffic explosion360 Gbps and 1.44 Tbps in 2012

13


14/16


Conclusion:Gateways outperform routers inconverged networks

Routers used to perform mobilegateway applications provide sufficientthroughput capacity for packet

forwarding, but fall short when it comesto meeting the needs of mobilenetworks in other aspects. Routers arealso unable to scale easily in line withthe changing traffic profile demands of mobile networks.

Routers typically lack sufficient capacityto handle high subscriber and sessiondensity and the huge signaling trafficand state information seen in networkstoday and which will increasesubstantially as LTE networks come on

line. Routers also lack the necessaryservice intelligence and policyenforcement capabilities required byCSPs.

These shortfalls arise because routersuse centralized control planeprocessing that can create a severe

bottleneck with respect to signaling andmobility, especially in LTE networks.Because they separate the control anduser planes, routers cannot adequatelyhandle the combination of data andsignaling traffic that mobile networkscreate.

Nokia Siemens Networks Flexi NetworkGateway is a purpose-built gatewaythat meets all mobile gatewayrequirements. Flexi Network Gateway isbased on an ATCA platform, which

achieves lower cost, higher performance and better flexibility than arouter-based platform. In January 2010,Current Analysis stated: Nokia

Siemens Networks packet core isranked No.1 based on impressiveGGSN capacity and service support.

Nokia Siemens Networks foresees thatfixed and mobile networks will continueto converge over the next few years.

Against this backdrop, implementingmobile packet core gateways that alsoprovide site router functions has manymore advantages than the edge router being enhanced with mobile gatewayfunctionality. Flexi Network Gateway asan intelligent edge can meet the needsof converged networks long into thefuture.

14


15/16


3GPP Third Generation Partnership Project AAA Authorization, Authentication, Accounting ASIC Application Specific Integrated Circuit ATCA Advanced Telecommunications Computing Architecture ATM Asynchronous Transfer Mode

BGP Border Gateway ProtocolBNG Broadband Network GatewayBRAS Broadband Remote Access Server BSC Base Station Controller CAGR Compound Annual Growth RateCOTS Commercial off-the-shelf CP Control PlaneCPU Central Processing UnitCSP Communications service provider DPI Deep Packet InspectionDSL Digital Subscriber LineDSLAM DSL Access MultiplexersEB ExabyteeNodeB LTE Base StationEPC Evolved Packet CoreEPS Evolved Packet SystemGi Interface to PDN, e.g. Internet

GGSN Gateway GPRS Support NodeGn Interface between SGSN and GGSNGPRS General Packet Radio ServiceGTP GPRS Tunneling ProtocolHD High DefinitionHDTV HD TelevisionHLR Home Location Register HSPA High Speed Packet AccessHSS Home Subscriber Server I-HSPA Internet HSPAIM Instant MessagingIMS IP Multimedia SubsystemIP Internet ProtocolLTE Long Term EvolutionM2M Machine-to-machineMME Mobility Management EntityMPLS Multi Protocol Label Switching

MPP Multi-core Packet Processor NodeB 3G Base StationP-GW Packet Data Network GatewayP2P Peer to Peer PCC Policy Charging and ControlPCRF Policy and Charging Rules FunctionPDH Plesiochronous Digital HierarchyPDN Packet Data NetworkPDP Packet Data ProtocolPICMG PCI Industrial Computer Manufacturers GroupQoS Quality of ServiceRAM Random Access MemoryRNC Radio Network Controller SDH Synchronous Digital HierarchySDRAM Synchronous Dynamic RAMS-GW Serving GatewaySGSN Serving GPRS Support Node

S/P-GW Serving GW / PDN GWTCAM Ternary Content Addressable MemoryTCP Transmission Control ProtocolUP User PlaneVRF Virtual Routing and ForwardingYoY Year on Year

Abbreviations

15


16/16

www.nokiasiemensnetworks.com

Nokia Siemens NetworksP.O. Box 1FI-02022 NOKIA SIEMENS NETWORKSFinlandVisiting address:Karaportti 3, ESPOO, Finland

Switchboard +358 71 400 4000 (Finland)Switchboard +49 89 5159 01 (Germany)

Product code: C401-00702-WP-201103-1-EN

Copyright 2011 Nokia Siemens Networks. All rights reserved.

Nokia is a registered trademark of Nokia Corporation,Siemens is a registered trademark of Siemens AG.The wave logo is a trademark of Nokia Siemens Networks Oy.Other company and product names mentioned in this documentmay be trademarks of their respective owners, and they arementioned for identification purposes only.

This publication is issued to provide information only and is notto form part of any order or contract. The products and servicesdescribed herein are subject to availability and change withoutnotice.

white paper flexi ng versus routers

Documents