The unified foundations

For most CIOs (chief information officers), the goal of putting all their organisation's applications, including voice and video, onto one big, simple and intelligent Internet protocol (IP) backbone is a top priority. Many have already done so, and, according to Forrester Research, an IT advisory company, about one-third of all organisations will have a unified IP network by 2010.

This rush to convergence is understandable. Many businesses, notes a recent report from Bearing Point, an analyst firm, currently have a patchwork of networks that are "cobbled together, often resulting in inefficiencies, high costs, inadequate disaster recovery and an inability to deliver new bandwidth-intensive applications". Even if the economic arguments were not so overwhelmingly in favour of standardising on one network, the technical ones – in terms of manageability and ease of use – would be.


Going mobile

Eventually, local area and wide area wireless networks will link seamlessly into fixed networks – with handover of services and billing occurring quietly in the background. Building out IP networks into the wireless world, however, is a difficult technical challenge that is further complicated by intense competition and by regulatory pressures.

The development of SIP and IMS technology will provide mobile operators with a technical platform to deliver presence and device ‘awareness' to IP-based networks, enabling application layer convergence of the mobile and fixed communications worlds. "Once you have a SIP-enabled phone, you won't even know you are on an IP network," says Paul Mankiewich, chief technology officer of mobility for Lucent's Bell Laboratories.

Rolling out the technology, say analysts, will take five to 10 years. At this point, services such as mobile VoIP, push-to-talk, and ad hoc voice and video conferencing should all become available.

But one big question remains: how will the mobile network operators support the all important real-time voice packets? At present, 3G cellular networks have too much latency to support VoIP.

The solution will come in the form of 3.5G – HSDPA (high-speed downlink packet access). Initial services are likely to run at about 3.4 megabits per second (Mbits/s), but this will rapidly increase. Equipment manufacturers believe they can reach speeds of 100 Mbits/s. According to Mankiewich, Bell Labs has conducted trials where it has been able to get better voice perfomance using VoIP than using circuit switched technology and GSM phones.

WiMax networks offer another wireless alternative. By 2007/8, WiMax networks covering a radius of some 4-6 kilometres should be widely available. With connectivity of between 0.5 Mbits/s and 75 Mbits/s, and little latency, they will be able to comfortably support VoIP.

The technology for the truly converged network is, therefore, in place. The major concern for operators is how they transform their business models.



But there are some big riders to this otherwise simple proposition. Building a successful, unified infrastructure, it turns out, is a far more complicated, and longer-term, project than many managers are anticipating. Most of the big projects publicised today are still in their early stages.

Basic beginnings

First, the assertion that full convergence is happening today needs clarification. Sometimes, the IP backbone covers only certain applications or geographies, and none so far reaches effectively into the all important area of mobile applications (see box, Going mobile).

Second, many integrated networks have not been designed to support the requirements of the truly unified networks that will emerge over the next several years. At the very least, networks will be required to support low latency applications such as voice, high bandwidth applications, such as video streaming, and resource hungry applications, such as transaction management. They must also be able to differentiate between applications so that their performance can be protected if necessary.

Furthermore, few networks have been modelled to anticipate how usage patterns might change once modern, converged applications are installed – and how these applications affect each other. Many businesses, having switched to IP-only networks, have encountered performance problems.

A third issue is that converging different core services onto the backbone, and even adding in advanced features such as ‘presence', using the session initiation protocol (SIP), is of limited value without upgrading, extending and even rethinking the array of applications and processes that will exploit the technology. "If you see this is a way of ripping out costs, you've missed the point of convergence," says John Wright, general manager, Mobility, BT Retail.

In most cases, enhancements will be handled by the major application providers, such as SAP and Microsoft; but in other areas, extensive upgrading and re-engineering will be necessary. A centralised platform to deliver services may be required.

Leading operators and equipment providers are aware of all of these issues, and are designing networks that are ‘application aware'. These vary in sophistication, in their adoption levels and in their ‘openness'. But none of these technologies are yet used on the ‘open'


The vision…and the reality


The network will be unified in every sense: for the user, the handover from a cellular service to a WiFi service or an ethernet connection will be seamless, whether the application is voice or data. All services and all users will be accessible from anywhere, one directory will serve all services, and communications between devices will intelligently sense formats and the context in which the service is being sent. For CIOS, it will be possible to manage this whole network with one set of tools and one set of service level agreements.


Most user organisations do not yet have unified networks and VoIP, the first big converged application, has only just reached maturity. Public telephone networks have yet to switch over from old style circuit connections, and mobile services lack bandwidth and full IP support. Most enterprise applications do not yet exploit convergence, and most installed networks do not yet use all the management functions becoming available. Convergence for most is five or ten years away, but early adopters are already seeing benefits.



Internet, so quality of service of, for example, voice over IP (VoIP), cannot be guaranteed unless it is supported from end-to-end by a network operator.

New standards

One widely adopted standard for improving quality is MPLS – multi-protocol label switching. This method, now widely supported by equipment makers, involves identifying the source of IP packets and attaching a label to them according to agreed priorities. From then on, all routers and switches on the network can prioritise the traffic.

In June this year, Cisco, the leading provider of IP telecoms equipment, introduced a more advanced set of products as part of its AON (application-oriented networking) architecture. This involves installing devices on a network (or upgrading some existing routers) that are capable of rapidly reading and understanding the context of the messages. For example, it might be able to differentiate between a purchase order and an invoice.

Nick Earle, vice president of marketing, planning and operations for Cisco, EMEA, says the innovation will have an "impact on enterprise IT architecture as profound as the migration from mainframe to client/server in the 1980s".

Many service operators and system integrators also address the potential application performance issues. BT, for example, takes a thorough, services-oriented approach based on taking a centralised view of the entire unified network. Its application assured infrastructure (AAI) involves analysing network requirements in advance, building performance models, and then implementing a converged network based on technology from a number of vendors.

IT analyst company Gartner says that service providers could soon be delivering application-level guarantees to more than one-third of their clients. But their challenge, it says, is to turn project work into a regular service.


Unification building blocks

IMS (or IPMS): The IP multimedia subsystem is a standardised architecture that specifies how network operators can provide converged multimedia services regardless of access technology, wired or wireless. Applications include push-to-talk, videoconferencing and content sharing. The advantages for operators include faster launches for new services and a central repository of user data.

IP: As communications mechanisms and access technologies converge upon the Internet protocol, truly unified communications become possible, with all voice and data carried over the same network.

SIP: The session initation protocol is the control mechanism at the heart of any converged network and device. Connection addresses can be associated with people rather than their communications mechanism, thus allowing one number for all devices. SIP provides ‘presence' awareness.

HSDPA: Also known as ‘3.5G', high-speed downlink packet access is a mobile data service capable of transfers as speeds of up to 10 Mbit per second. This will enable it to support IP multimedia services. Mobile operators plan to deploy HSDPA in 2005-6.

AON: Application-oriented networking devices from vendors such as Cisco and 3Com intelligently process XML and other messages to help tune the IT infrastructure for a service-oriented architecture, application acceleration, quality of service and integration.

MPLS: Multiprotocol label switching is a data-carrying mechanism, designed to unite traditional circuit-switched and new packet-switched networks. It also prioritises the transmission of data packets depending on their needs.

3G: Third-generation mobile data services technology brings faster transmission speeds to phones and laptops than exsiting GPRS systems and enables video calling and other real-time data intensive services.

WiMax: A wide-area (4-6 kilometres) wireless broadband technology, initially used by service providers for backhaul. When the latest 802.16e standard is ratified, it will be used by individuals' mobile devices in much the same way as WiFi networks are now. Trial services are already underway.



Perhaps the biggest infrastructure challenge, however, is architectural. How are these new, unified IP-based services and applications to be delivered and integrated – and how is it be done rapidly, flexibly and cost effectively?

The telecoms companies, both mobile and fixed, have the answer, in the form of the IP multimedia subsystem (IMS), which will ultimately work on top of a pure IP infrastructure. IMS is an open platform based on SIP and enables the service providers to develop, deliver and manage IP-based services that are end-user and device aware. To those with an enterprise IT background, it is analogous to the way that web services orchestration platforms can be used to deliver plug in services for the service-oriented architecture.

The IMS is capable of supporting a large number of add-on services, and will be able to manage important functions such as security, identity management and billing. For this reason, the service operators see it as vital – if expensive. Forrester Research recently said that IMS systems could cost operators hundreds of millions of dollars each to build.

Analysys, a telecoms research company, recently forecast that all the major mobile operators would deploy IMS systems within five years – even though it warned that these systems are expensive and risky. Although IMS platforms were originated by mobile operators, however, they are likely to be more widely adopted, with major fixed-line operators also seeing this as a way to gain a competitive edge over rivals. By installing a good IMS, operators will be able to deliver a richer variety of services to their customers, often more quickly and more flexibly than those using alternative approaches.

This raises the question: Will IMS also be important to enterprise customers? "We think so. But it probably won't be called IMS," says Jerry Caron, an analyst with Current Analysis, who foresees the development of similar tools for use by enterprises.

Using the IMS model, he says, it will be possible for enterprises to build a framework for cost effectively delivering IP services, such as VoIP, video-enabled applications and ‘presence'. These networks will be able to link seamlessly into external networks, so in this way, some business will be able to become their own carriers – at least for part of the network.

Application platform

One of the benefits of SIP and the IMS model is that it should prove flexible enough for operators (and enterprises) to add in new application functions – even those have yet to be invented or articulated. IMS has been compared to enterprise resource planning (ERP) systems, in that it could support a huge range of corporate applications.

One example is the use of context and profile data, which is not yet supported by SIP and IMS . "There is a third leg (after signalling and traffic bearing) that's coming into telecommunications – a hidden revolution, and that is context data," says Rick Hull, head of network data and service research for Bell Labs, now part of Lucent Technologies.

Context may involve, for example, giving the messaging service information on user context as well as explicit preferences, possibly by profiling recent phone calls and analysing the user's relationships and history. Without this, the new infrastructure could add more complexity, rather than make it easier to use.

With so much complexity, one question repeatedly arises. How much of this will businesses hand over to service operators, and how much will they do themselves? In theory, it will be possible to build or enhance most next generation network applications in-house, especially using tools such as Microsoft's LiveLink server, and link these to SIP-aware services running on remote networks. But most CIOs are likely to weigh up the risks and rewards and opt for an outsourced service, even if they retain some critical applications in house.

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Ben Rossi

Ben was Vitesse Media's editorial director, leading content creation and editorial strategy across all Vitesse products, including its market-leading B2B and consumer magazines, websites, research and...

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