technical ip convergence w - recursos · pdf filetechnical ip convergence w ... cable &...

technicaloverview

IP convergencesolutions in practice

enabling e-Business through workableconvergence solutions

Key topics

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IP telephony

real-time IP

budgetary convergence

intranets

virtual private networking

‘click to call’

unified messaging

This Technical Overview looks at the practical issuesinvolved in the migration towards integrated networkscarrying multimedia traffic.

examines the context in which enterprise networksare evolving towards widespread deployment of , and thefactors driving convergence.

discusses the future of networking, and thebenefits that convergence will bring, in the form of newintegrated applications and extended access to corporateresources.

addresses some practical issues which the NetworkManager needs to address in moving towards fullconvergence while minimizing risk and disruption. Itconsiders two possible scenarios to illustrate how solutionsfrom Cable & Wireless are designed to simplifyand facilitate the migration.

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Part

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overviewtechnical

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Contents1 Background — drivers for change 2

What’s typically in place now 2

In the local area

In the wide area

New pressures on the network 3

Challenges faced by IT staff 4

Evolution in service delivery 4

The trend towards virtual private networking 4

A new generation of VPNs 4

2 The new enterprise network 5

Steps towards the converged network 5

Establishing an IP-VPN

Bringing voice onto the IP network

Benefits of convergence 7

Economies of scale

Reduced call charges

Integrated applications

Widening access

3 Solutions in practice 9

Budgetary convergence 9

Mitigating risk 9

Auditing your current network 9

Scenario 1: change driven by data requirements 9

Phase 1 — subsidiary working

Phase 2 — adding an IP-PBX server

Flexibility in the LAN

Scenario 2: change driven by voice requirements 12

Convergence in the wide area 13

Adding new applications 13

A predictable pricing model 14

Opening up new possibilities 14

Convergence as an enabler for e-Business 15

Cable & Wireless: Delivering the Internet promise 15

4 Index 16

IP convergence technical overview 1



1 Background — drivers for changeSection 1 outlines the context in which enterprise networks are evolvingtowards widespread deployment of IP and eventual convergence.

What’s typically in placenow

In the local area

Figure illustrates a typical config-uration at a single location, withvoice and data carried over separateinfrastructures and covered byseparate budgets for equipment,cabling, management and mainten-ance. This generally consists of:

• An Ethernet data , carrying and legacy traffic between s.Connections typically use Cate-gory (Cat-) or Cat- cabling.

• A for switching voice trafficbetween extensions and outsidelines, with telephones on thedesktop and dedicated cabling.

In the wide area

Figure shows what organizationstypically have in place for inter-sitecommunications. As in the ,voice and data communications areusually covered by separate budgets.The typical wide area enterprisenetwork might include:

• A corporate data network basedon frame relay, , privatecircuits or a combination, with (intranet) and legacy traffic carriedover links with requirements for acommitted data throughput.Different classes of service (CoS)may be available to supportparticular applications — forexample, an constant bit rate() service for realtimeapplications such as video.

2

data networkmanagement

‘data’ budget

‘voice’ budget

PBX management

router

Corporate WANInternet

PSTN and PSTN-basedvoiceVPN services

PBX

Category 3 (Cat-3), Cat-5 orCat-6 twisted-pair cabling

Telephone cabling

$

$

Figure 1. The pre-convergence LAN

The irresistible rise of Internettechnology

In a recent survey of the NetworkManagers of 251 major corporations,91% reported that IP is now thepredominant protocol on theircorporate network, or intranet. Morethan 35% of these communicate withother organizations via anextranet — a group of intercom-municating intranets, with accessrestrictions to isolate it from the widerInternet.

There is also a significant movetowards virtual private solutions.Overall, 42% of businesses in the UK,and 47% in the Netherlands, now seeIP-VPNs as the future. This figure risesto over 70% among Law firms — asector which by definition insists onthe highest levels of data security. Thispositive attitude reflects growingconfidence in IP as a secure, proventechnology.



• Some form of protected dial-upaccess to the corporate networkfor mobile and home workers— for example, the Cable &Wireless SecureDial service.

• Internet access, with a publiclyavailable web site for e-trading,marketing, etc. With an extranet,authorized users outside theenterprise may be granted accessto parts of the intranet viaInternet connections.

• lines for voice calls. Forintra-company voice traffic, manyorganizations use a managed,public network-based service likeCable & Wireless GlobalIntelligent Virtual Network,which provides a short-code DialPlan between sites, and incurslower call charges than standard services.

New pressures on thenetwork

Over the past five years or so, severalfactors have driven the need toupgrade communications andcomputing infrastructures.

• With more processing power onthe desktop, users are runningmore (and more complex) appli-cations, placing heavier demandson the network.

• Available bandwidth within the has increased in response tochanges in the type and volume oftraffic and the need for resilience.Increasingly, users have Mbit/sconnections to the desktop, andsome now have Gigabit Ethernet.

• The ‘desktop’ is no longergeographically fixed — staff needthe flexibility to access thecorporate network while travelingor working from home, and toshare desks in the office whennecessary.

1 Background — drivers for change


Corporate data WAN

QoS

PSTN

Internet

VoiceVPN services

PVCs

Frame relay/ATM networkHead office

Branch office

Branch office

Branch office

PBX

switch

router

no QoS

Frame relay/ATM access circuit

Frame relay/ATM PVC

PSTN line

Internet access (could be PSTNdial-up, private circuit or via aframe relay network)

Intranet traffic is carried overa frame relay/ATM core, withend-to-end QoS guarantees.

Figure 2. The pre-convergence enterprise network



Challenges faced by IT staff

The technical difficulties faced by staff are compounded by radical andrapid changes in the businessenvironment.

• Globalization means they mustdeal with more widely dispersedlocations, working across nationalboundaries.

• With mergers, acquisitions andreorganizations, sites often need tobe added to or removed from thenetwork at short notice, andprovided with the ability tocommunicate directly with oneanother in a meshed network.

• Applications also need to beadded, modified and removed asbusiness requirements change.

• Web pages are becoming morecomplex, expanding from simpletext and graphics to interactivemultimedia applications whichsupport e-Business.

Evolution in service delivery

The ‘traditional’ corporate datanetwork was based on privatecircuits, with fixed bandwidthbetween fixed locations. Now thatneither bandwidth requirements norlocations are fixed, this arrangementlacks the necessary flexibility andscalability.

Circuit-switched networks havelargely been replaced by packet- andcell-switched technologies such asframe relay and , with virtualconnections sharing bandwidth bystatistical multiplexing. This allowsfor a more efficient and cost-effectiveuse of bandwidth, especially for thebursty traffic carried over datanetworks.

Most of these technologies remainconnection-oriented, however, withspecified locations linked by perma-nent virtual circuits (s). Addingnew sites to an enterprise networkstill involves the provisioning of news and reconfiguring equipment,and access bandwidth is a limitingfactor.

The next step is to dispense withcircuits altogether, and use con-nectionless technology such as .Users, sites and devices can be addedto or removed from an -basedenterprise network at any time, bysimply validating user s andpasswords. An network is, bydefinition, meshed — a single,straightforward connection to apublic network Point of Presence(PoP) gives any-to-any connectivity,with no need to worry aboutconfiguring virtual circuits to shareaccess bandwidth.

The trend towards virtualprivate networking

As the enterprise network becomesmore inclusive and wide-reaching,the challenge of day-to-day manage-ment can be a distraction from thestrategic planning and innovationnecessary for continuouscompetitiveness.

Businesses are increasingly turningaway from fully ‘private’ networkingsolutions, and relying on operatorslike Cable & Wireless to supply andmanage their infrastructure, allowingthem to:

• reduce capital investment andmanagement overheads

• concentrate their own resourceson developing and supportingapplications

• benefit from the performance,reliability and capacity of a public

network, and the expertise andaround-the-clock availability ofspecialist staff

• be confident that future upgradepaths are built into the solution,thus mitigating technical risks

This is the virtual private network() — a solution providing securetransport of private traffic acrosspublic network infrastructure, withService Level Agreements (s)defining availability andperformance. -compatible sare known as -s.

A new generation of VPNs

was not originally considered tobe appropriate for running business-critical applications over an enter-prise network, because it could notdeliver guaranteed QoS, and securitywas a major concern.

With the development of Multi-protocol Label Switching (),s can now be configured acrosspublic networks with thenecessary QoS guarantees fordifferent traffic types, includingrealtime voice and video. For moreinformation about , see the boxon page .

As for security, with plus fire-walls and encryption techniques, -s can be made as secure as thefully ‘private’ alternative, with theadded advantage of providing easierand more flexible control over users’access to specific information.

1 Background — drivers for change

4



2 The new enterprise networkSection 2 looks into the future of IP networking, and at the benefits thatconvergence will bring.

Steps towards theconverged network

Figures and show how a typicalenterprise network might evolvetowards convergence.

Establishing an IP-VPN

One possible starting point is toreplace the existing infra-structure with an -, using to provide consistent,guaranteed QoS.

This new network will be flexibleand scalable, so that new users, sitesor applications can be added andintegrated whenever necessary.

Bandwidth is plentiful at the core,and can be added to access circuitswith no need for majorreconfiguration.

Migration won’t happen overnight— in most cases, the - willneed to be integrated with existinginfrastructure (e.g. ) for sometime. An advantage of in thisrespect is that it is a multi-protocoltechnology — the label-switchedpaths which are routed through an system can be switched by switches as well as by routers, allowing traffic to becarried across an core.


IP-VPN QoS

MPLS

PSTN

Internet

VoiceVPN services

Head office

Branch office

Branch office

Branch office

PBX

IP network

Access circuit

MPLS label-switched path

Physical edge router

MPLS router

Data and multimedia is carriedover the IP-VPN. Intranet andInternet traffic share anintegrated access circuit.

Figure 3. Data on the corporate IP-VPN

Categories of cabling

The unshielded twisted pair cabling(UTP) used in LANs is categorizedunder the EIA/TIA*-586 standard,according to the data transmissionspeeds supported, as follows:

• Category 3 (Cat-3) — up to10 Mbit/s

• Cat-4 — up to 16 Mbit/s

• Cat-5 — up to 100 Mbit/s

• Cat-5E — up to 1 Gbit/s

• Cat-6 (yet to be ratified) — Gigabitand beyond

* Electronics Industry Association(USA); Telecommunications IndustryAssociation (UK)



2 The new enterprise network

6

IP-VPN QoS*

MPLS

PSTN

Internet

Head office

Branch office

Branch office

Branch office

IP-PBX

IP-PBX

IP network

mediagateway

Media gateways between the IP networkand the PSTN will eventually allow localbreakout of external calls at the publicnetwork level rather than at the PBX.

* IP-VPN QoS will be availableat US sites in the near future.

All internal traffic, including voice,is carried over the IP-VPN.

The IP-PBX is connected onthe LAN. External voice callsbreak out to the PSTN, via anISDN Primary Rate Interface(PRI) card.

Router with PRI

Figure 4. The converged enterprise network

integrated networkmanagement

integratedmultimediaapplications

router

IP phone

PBX softwareserver(IP-PBX)

Corporate IP-VPNInternetGateways to PSTNfor external calls

Cat-5E/Cat-6 twisted-paircabling

$ single integrated budget

single Cat-5E/6 cablingport per extension

Figure 5. The converged LAN — integrated services to the desktop



Bringing voice onto the IP network

With the - in place, andplenty of spare capacity, internalvoice traffic can be routed over it.Voice calls consume relatively littlebandwidth, especially with com-pression techniques, and thus placevery little demand on the network.

Within the converged , therewill be just one cabling and switch-ing port per user, with integratedcabling (Cat- or Cat-) connectedto the desktop (Figure ). Telephoneshave been replaced with phones,connected directly to the .

Initially, sites will retain connections for external (outside ofenterprise) voice calls, which will beswitched either by an - con-nected on the (see the box onpage ).

In the future, separate connectionswon’t be necessary — external callswill be carried over the networkand broken out locally onto the via media gateways.

Some existing connections canbe kept as a backup resource in caseof emergency.

Benefits of convergence

Full convergence will bring togetherbusinesses’ information strategiesand communications strategies forthe first time, resulting in costsavings and improved efficiency andflexibility.

Economies of scale

With voice, data and video sharingboth infrastructure and equipment,the cost of ownership is greatlyreduced. A single budget now coversall access lines, equipment, cabling,installation, management andmaintenance.

With managed service options fromCable & Wireless, businesses canfurther reduce capital investment andmanagement overheads, focusingresources on strategic planning andapplication development andsupport.

Reduced call charges

Intra-company voice calls mayaccount for a significant proportionof monthly phone bills, even withthe lower charges incurred using a-based voice service. Thisparticularly applies to internationalorganizations. By routing internalcalls over the -, usage-basedcharges are eliminated.

For international calls outside thecompany, it may be possible toreduce charges by routing the callover the corporate network to theoffice nearest to the destination andthen breaking out locally to the.



MPLS — the key to IP-VPNs

Multi-protocol Label Switchingenables the provision of secure VPNs,with guaranteed QoS, over an IPnetwork.

With MPLS, there are no permanentvirtual connections between sites.Instead, secure, logical paths are setup through the network as and whenthere is traffic to deliver, using thebest route available at the time. Thismeans that users, sites or devices canbe added to the network at any time,without reconfiguration and withoutaffecting security or reliability.

In technical terms, MPLS makesrouters behave similarly to switches,integrating layer 2 (data link)information about network links(bandwidth, latency, utilization, etc.)with the layer 3 information in IPheaders (source and destinationaddresses, type of service and QoSrequirements).

The key feature of MPLS is theaddition of a short, fixed-length labelto each data packet that enters thenetwork. The labels act as ashorthand representation of the IPheaders, and are used to assignpackets to label-switched paths(LSPs). High-speed routers in the corenetwork use signaling information todetermine the routing of LSPs, takinginto account network conditions. Inessence, these routers make switchingdecisions based on the headers.

Media gateways

Media gateways allow voice traffic tobe passed between IP infrastructureand the PSTN, by providing conversionbetween the information carried ontelephone circuits and the datapackets carried over IP networks.

The call-control intelligence for severalmedia gateways is handled by amedia gateway controller(MGC).

Communication between gatewaysand MGCs uses the MediaGateway Control Protocol(MGCP), defined by the InternetEngineering Task Force (IETF).



Integrated applications

With applications sharing both infrastructure and end-points, voice, data andvideo can be integrated to keep up with new working arrangements andbusiness practices. Examples include:

• With unified messaging, users have a single inbox for voice messages, faxes,email and Short Message Service () messages from cellular phones. Theycan access their in-boxes from anywhere in the world, either from atelephone or via the Internet, to send and retrieve any type of message.

• ‘Meeting’-type and collaborative applications, which combine audio- andvideoconferencing, whiteboarding, etc. allow people to share resources andexpertise whenever they need to and wherever they are.

• Currently, many organizations have both call centers and websites, but theseare usually separate. Full computer–telephony integration () to thedesktop will enable the development of integrated call centers — forexample, the customer and call center agent will be able to view the sameproduct description or demonstration on screen while talking to each other.

• ‘Click to call’ facilities will allow users to set up voice calls by clicking onlinks on websites.

• Applications like distance learning will be enhanced by the ability to embedvoice links into electronic documents.

• With multicasting, organizations can make interactive training andinformation videos available to staff, who view them on their desktops ratherthan having to go to dedicated meeting rooms. Multicasting is also a cost-effective way of disseminating corporate messages.

Widening access

The network gives users -hour access to information and networkresources, from any location. All they need is a valid address and password,and a connection to the fixed or mobile public network.

Voice calls will be able to locate the recipient anywhere on the network, usingthe address.


8

The IP-PBX

Unlike traditional PBXs, which requirededicated (and costly) call-processinghardware, IP-PBXs run as softwareapplications on a network server.

IP-PBX software extends enterprisetelephony functions to packettelephony devices such as IP phones,multimedia processing devices andVoIP gateways.

IP-PBXs provide all the familiar PBXfeatures such as hold, transfer, divert,speed dialing, conference calls, etc.Reconfigurations and upgrades arecarried out through the software.

With some IP-PBXs, multiple serverscan be ‘clustered’ and managed as asingle, distributed, multi-site system,allowing capacity to be scaled up toinclude tens of thousands of users.Clustering also builds redundancy intothe system, improving availability andreliability.

IP-PBXs may be configured auto-matically to divert calls to the PSTN(via an interface such as ISDN PRI) ifbandwidth is not available in theWAN.



3 Solutions in practiceSection 3 considers how organizations might move towards full IP convergencewhile minimizing risk and disruption. Solutions from Cable & Wireless arespecifically designed to simplify and facilitate this migration. Two hypotheticalbut typical scenarios are discussed.

Budgetary convergence

While the benefits of convergenceare not questioned, in reality organiz-ations do not, without good reason,change what already works. Networkdevelopments will be driven by need,as the existing infrastructure becomesinadequate for supporting newapplications, additional users orcorporate expansion.

Any new investments in telecom-munications or data networks shouldhave convergence factored intothem. As the network evolves, thetraditional voice and data budgetswill converge, freeing up resources forfurther innovation and the develop-ment of e-enabled business.

The way this happens will depend onindividual circumstances. In practice,the process will usually be a phasedtransition rather than an overnighttransformation.

Mitigating risk

One reservation shared by networkmanagers about convergence is thatstandards for o are still in a stateof flux, with no clear consensus as towhich one will eventuallypredominate.

The . standards defined by theInternational TelecommunicationsUnion () represent the ‘voice-oriented’ approach, while SessionInformation Protocol (), definedby the Internet Engineering TaskForce () is seen as ‘data-oriented’. It is probable that morethan one standard will exist for theforeseeable future.

In the face of this uncertainty, anycommitment to capital investment isseen as risky, and managers may wishto delay major decisions.

Managed solutions from Cable &Wireless provide low-risk migrationpaths, with predictable pricingmodels, and rental options whichreduce capital investment. Built-inupgrades allow you to keep up withnew developments. And becauseCable & Wireless services are fullystandards-based, there’s no danger ofbecoming locked in to a proprietarysolution.

Auditing your currentnetwork

Before recommending a course ofaction, Cable & Wireless will workwith you to evaluate your currentnetwork, your priorities and yourrequirements for the future, askingquestions like:

• What are your voice and datatraffic volumes and profiles?

• How closely will you want tointegrate voice and data?

• What is your user profile? Whatproportion of your staff uses their most of the time?

• How much is your costingyou? You need to consider theongoing costs in terms ofupgrades to memory, software,hardware, firmware, etc. requiredto accommodate new users oradditional traffic.

• How do you handle incomingcalls? Are most of your calls

answered by an operator, or docallers dial direct to users’ desk-tops? Or are you running a callcenter-type application?

• How many sites do you have? Ifyou run a multi-site operation,how about using a centralizedoperator? How important is -type feature transparency betweensites?

Scenario 1: change driven bydata requirements

In this scenario, an organizationneeds to upgrade its corporate datainfrastructure — for example, to rollout new applications, to accommo-date new users or to migrate from to .

As for voice traffic, the existing currently meets the needs of mostusers. But its capacity is stretchedand upgrading or replacing it wouldbe costly. Therefore, any solution tothe data requirements must includenew voice capacity, with a view toeventual convergence.

Figure 6 (page ) shows a possiblephased approach, based on theCable & Wireless - service(see the box on page ). Cabling isupgraded as necessary, by providingCat- or Cat-6 to each desktop. Allnew user ports are o ready, withequipment either purchased ascapital, or leased on a per-port basis.A single network port for each userwill cater to both voice and dataneeds, with significant cost savings.

A layer switch (see the box on page), which supports voice as well asdata traffic, links the various networkelements.




3 Solutions in practice

10

IP-PBX

WAN — virtual privatenetwork using public networkinfrastructure for integratedservices. External voice callswill eventually break out at thepublic network node.

IP phones

IP phones

‘soft phone’

layer 3switch

layer 3 switch

workgroupswitches

workgroupswitches

Cat-5 cabling

Cat-5 cabling

One port per user

One port per user

All new data portsareVoIP-ready.

PHASE 2, continued

n

n

Add an IP-PBX (CallManager) software server.

Add additional IP phonesas necessary, with orwithout PCs.

PHASE 2

n Gradually phase out thelegacy PBX.

Add a router with PRI ports.n

PHASE 1n

n

n

Add IP phones to LAN portsfor new users.

For PSTN access, ‘piggyback’off the existing PBX, usingQ.931.

Retain existing digital andanalog extensions.

Q.931 card in PBX(supports up to about100 IP extensions)

Server with callmanagement software

24-channel (T1)connection

router/gateway

corporate dataWAN router

router withPRI ports

dial-up PSTN lines and access circuits to voiceVPN

dial-upPSTN lines

digital/analogueextensions

Figure 6. A transitional approach towards convergence, using Cable & Wireless IP-LAN



Phase 1 — subsidiary working

Initially, for access to the , the life of the existing is extended usinga form of ‘piggybacking’, or subsidiary working, as shown in the first part ofFigure .

Using the . signaling standard, the is linked via a specializedrouter or gateway to a segment. phones are installed on the for theadditional users, and integrated with their s if required.

A single . card (which occupies a extension slot) can support up toabout phones, with or without s.

To manage the Dial Plans for the new extensions, call management softwareis installed onto a server.

Phase 2 — adding an IP-PBX server

Later, an - software server is added, with phones on the desktop and asstand-alone units without s where necessary. This equipment can be afurther capital purchase or an add-on to the initial managed service contract.

Flexibility in the LAN

An - solution is especially appropriate for organizations looking todevelop more flexible working practices. Examples of -’s flexibilityinclude:

• The ability to configure virtual s (), minimizing networkcongestion by grouping ports that exchange a lot of traffic. s operateregardless of which physical port each user is connected to, so they simplifyadditions and changes of equipment and ports, and facilitate ‘hot-desking’.

• Wireless s, which are ideal for touchdown areas, where users can havewireless access to the without plugging their equipment into a physicalport. Cable & Wireless uses Cisco Aironet equipment, supplying datarates of up to Mbit/s depending on conditions.



Layer 3 switching

Switches traditionally operate at layer 2, the data link layer of the OSI model. Theygive of high throughput and low latency; but are limited in their scalability andflexibility, and in their support of multimedia and multicasting.

Routers operate at layer 3, the network layer, and can provide for security featuresand differential QoS requirements. But with their higher processing overhead they runthe risk of congestion in very busy networks.

Layer 3 switches combine the speed of layer 2 switching with the intelligence of layer3 routing. While routers carry out the processing in microprocessor-based engines,layer 3 switches use application-specific integrated circuit (ASIC) hardware to achievemuch higher forwarding rates than conventional routers.

Cable & Wireless service info

IP-LAN

IP-LAN is a complete, scalable LANconnectivity solution for sites with 100or more users. It includes:

• equipment (Cisco Ethernetswitches), which can be leased on aper-port basis or purchased

• design and installation services

• cabling upgrades if necessary

The three management options, allbacked by SLAs, are:

• Maintained — equipmentmaintenance and upgrades

• Monitored — proactive faultdetection

• Managed — the mostcomprehensive monitoringand management option

The Technology Refresh optionoffers regular upgrades to equipmentor software, also on a price-per-portbasis.



Scenario 2: change driven byvoice requirements

In this scenario, the organization’s is no longer adequate, and extravoice-traffic capacity is needed.Managers are hesitant to startinvesting in infrastructure whichmay become obsolete within acouple of years.

The Cable & Wireless Convergence Plus service (see the box onpage ) provides an answer, in theform of low-risk phased migrationfrom a traditional to a full telephony solution. The existing is replaced by a managed NortelMeridian , on an initial fixed-term contract, with a mixture ofstandard and extensions. Thetransition to telephony takes placeover the contract term.

Convergence Plus is particularlysuitable for applications whichdemand sophisticated featuressuch as centralized operators, audioconferencing or networked voicemessaging. It also includes severaloptions for call centers — from basicsoftware for simple agent working,up to enhanced server-based servicesthat support very high trafficvolumes.

The service has advanced networkingcapability. Figure shows how theInternet Telephony Gateway ()card can be used both for connecting extensions within the , andfor interconnecting sites over the, providing cost savings onintra-company calls. The Nortelsignaling standard, MeridianCustomer-defined Networking

(), provides feature trans-parency between Convergence Plus sites. Sites with other s canbe included in the network, using. for some feature transparency.

Policy management capabilitiesinherent to the gateway measure thenetwork QoS, and automaticallyreroute voice calls over the when necessary.

Pricing of Convergence Plus isbased on a simple and predictableformula — equipment, features andoptions are costed out on a per-extension basis. This makes it easy tobudget for additional extensions asthe system grows with your business.


12

digitalextensions

Meridian 1 PBX

CUSTOMER’S PREMISESCABLE & WIRELESS NETWORK

analogextensions

IP extensions

IP phone

switches

C&W Convergence PBX Plus

LAN

corporate data WANCat-5E cabling

ITG LAN cards

ITG WANcard

dial-up PSTN lines; access circuits to voiceVPNPBX monitoring link

Internet TelephonyGateway (ITG) cards

router

Figure 7. The Cable & Wireless Convergence PBX Plus approach to convergence



Convergence in the widearea

At the same time as the isupgraded, the need for extra capacityand flexibility in the wide area is metby migration to the Cable & Wireless- QoS service (see the boxbelow), with Class of Service optionsappropriate for the applicationsbeing run.

Managers can therefore concentrateon developing and delivering newapplications, confident that theinfrastructure exists to deliver them,backed by comprehensive s. Forexample, the Premium service optiondelivers realtime — transport of packets at sub- ms latencies,supporting realtime traffic.

For the time being, organizationswill retain public exchange lines(typically Mbit/s circuits) forexternal voice calls, while intra-company calls will be routed over the. Eventually, it should bepossible for all traffic to be carriedover shared access circuits, withexternal calls breaking out at a publicnetwork node.

Adding new applications

The point at which individual users’desktops are converted fromstandard extensions to integ-rated ports will depend partly ontheir need for new applications.

These applications include:

• Multicast services, an economicway of delivering trainingmaterial, corporate messages, etc.to users, who can sit at their desksand receive broadcast -stylecontent.

• Unified messaging — Cable &Wireless can give users messageboxes which receive voice, emailand fax, with some ability totransfer messages between them.This allows on-the-road staff toaccess their email over thecorporate and to receivevoice mail without payinginternational call charges.

See page for more informationabout integrated applications.



C&W service info

Convergence PBX Plus

This fully managed service is designedas part of a convergence strategyfrom a traditional PBX to a fullyintegrated IP-PBX platform. It isavailable on a rental basis only, withno capital outlay for customers.

The service is based on the industry-leading Nortel Meridian PBX range.It supports between 16 and 16,000extensions on a single system, andincludes:

• the PBX

• extension equipment

• connection (direct or indirect) tothe Cable & Wireless network

• installation and configuration

• cabling where necessary

• scheduled software and hardwareupgrades

• a range of options for applicationssuch as call centers

Three options are available for eachextension:

• a standard digital voice extension,with a choice of handsets

• IP migration, starting with a digitalextension and allowing swap-out toa VoIP port, equipped with an IPphone, during the term of thecontract

• an IP phone from day one

Figure 7 shows Convergence PBX Plusconfigured as a hybrid system, with amixture of extension types.

Cable & Wireless service info

IP-VPN QoS

This fully managed private network service will be available at US sites in the nearfuture. It uses the shared Cable & Wireless IP network infrastructure to providecustomers with any-to-any connectivity within a defined VPN, with an optionalfirewalled connection to the Internet.

The service uses MPLS at the core, offering much higher QoS levels than theservices delivered over the public Internet, together with a level of security equivalentto that in a fully private network.

Three prioritization levels, or Classes of Service (CoS) are available:

• Premium — realtime IP, for time-critical traffic such as voice and video

• Enhanced — for business-critical traffic such as transactions

• Standard — for non-critical traffic such as email

A single access link can be configured with a range of Classes of Service.



A predictable pricing model

With such fundamental changestaking place, managers need to feelthat they have a handle on theirbudgets, and that costs will not spiralout of control.

Cable & Wireless uses a simple andconsistent pricing structure for itsmanaged convergence portfolio,charging for each option on a per-userbasis, with management andmaintenance built into the cost.

Managers can therefore plan accu-rately for the future, allocatingresources according to the individualneeds of users.

Opening up new possibilities

A converged network offers enterprises more than just cost savings and newapplications; in a fully -enabled environment, businesses can find moreeffective ways of communicating with customers and associates.

A key feature of Internet telephony is Click to Call. A user browsing a website can click on a link to set up a simultaneous voice call using the sameconnection. The call can then be dynamically routed according to variouscriteria — the caller’s location, the availability of staff to take the call, time ofday, etc. As they talk, both parties can simultaneously view the same webscreen shots.

Within the enterprise, Click to Call facilitates collaborative working andincreases efficiency. And as more home users get access to high-speed Internetlinks, it will allow businesses to provide better service to online shoppers andpeople requiring customer service. The NetMeeting software that users needto set up o calls is included with Microsoft Windows® , and istherefore finding its way into many homes. Users’ only additional requirementwill be a microphone or other . input device. Alternatively, some of thenew generation of stand-alone web-browser phones will be .-compatible;and set-top boxes may soon be available, opening this capability up to thedigital market.


14

Figure 8. Simplified budgeting for current and future applications



Convergence as an enabler for e-Business

The services described in this Technical Overview are fundamentalcomponents for the delivery of an e-enabled infrastructure to supporte-Business. They have been designed to provide solutions based ontraditional communications budgets, thus focusing the next round of spending on driving the upgrade of the enterprise network towarda full e-Business environment.

The delivery of end-to-end QoS and voice/data integration arefacilitated by Cable & Wireless’s solutions for national, regional andglobal requirements. They provide the foundation for otherapplications and services, maximizing business benefits in theemerging electronic marketplace.

Cable & Wireless: Delivering the Internet promise

Cable & Wireless delivers the Internet promise to businesses in countries worldwide. With one of the fastest global Internet networkson the planet, we can help you succeed in e-Business with a full rangeof connectivity, web hosting, e-Commerce, voice and data or solutions. Visit our web site for more information.



Contact informationFor more information on business solutions and services, speak to yourCable & Wireless sales associate, or visit the Cable & Wireless web site:

http://www.cw.com

For more information on Cable & Wireless’s Convergence Solutions, emailus at [email protected], or visit the Cable & Wireless web site:

http://www.cw.com/us/convergence

Full details of the individual Cable & Wireless services described in thisTechnical Overview can be found on the C&W Consultants’ web site:

http://www.cw-reference.com/consult

This includes complete Service Descriptions, briefer Service Summaries and atechnical Glossary covering many terms associated with networking andother communications technologies.



16

4 IndexAATM, 2, 5

CC&W Convergence PBX Plus, 13

C&W IP-LAN, 11

cabling, 5

call centers, 8

Cat-5, etc., 5

Cisco equipment, 11

Click to Call, 14

connection-oriented technologies, 4

Convergence PBX Plus, 13

Ddigital TV, 14

distance learning, 8

Fframe relay, 2

H‘hot-desking’, 11

H.323, 9, 14

Iintegrated call centers, 8

International TelecommunicationsUnion (ITU), 9

Internet Engineering Task Force(IETF), 9

Internet telephony, 14

Internet Telephony Gateway (ITG)card, 12

IP-LAN, 11

IP-PBXs, 8, 11

IP-VPN QoS service, 13

Llayer 3 switching, 11

MMedia Gateway Control Protocol(MGCP), 7

media gateways, 7

Meridian Customer-definedNetworking (MCDN), 12

Microsoft NetMeeting, 14

multicasting, 8, 13

Multi-protocol Label Switching (MPLS),4–5, 7

NNetMeeting, 14

Nortel equipment, 12

Ppermanent virtual circuits (PVCs), 4

pricing model, 14

QQ.931, 11feature transparency, 12

Rrealtime IP, 13

SSession Information Protocol (SIP), 9

Ttouchdown areas, 11

Uunified messaging, 8, 13

Vvirtual LANs (VLANs), 11

VPNs, 4

Wwhiteboarding, 8

wireless LANs, 11



Cable & Wireless8219 Leesburg Pike,Vienna,Virginia 22182 www.cw.comCable & Wireless pursues a policy of continuous development of its products and services.This document is for guidance only and does not form part of any contract. It is subject tochange without notice.

©2001 Cable & Wireless USA. Inc. All rights reserved. 99259-9/01


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