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The Next Generation Network

Convergence is the word as networking vendors roll out an architecture that delivers a slew of services over a common IP-based infrastructure. Priya Jain reports

A next generation network (NGN) represents the convergence of network infrastructure and services, and integrates service provider offerings with Internet Protocol (IP) as the underlying technology.

Networking companies such as Cisco, Juniper and Nortel are making an attempt to bring next generation offerings to India. These are expected to deliver seamless transmission and integration of multiple services like data, voice and video to provide the required bandwidth and quality of service (QoS). These NGN services are to be delivered through IP-enabled MPLS networks.

"NGN infrastructure permits the convergence of all applications and services on to a single infrastructure with the needed QoS and bandwidth" - Prasad Babu Head, Systems Engineering India & Saarc Juniper Networks

The International Telecommunication Union (ITU) has specified the fundamental characteristics of the IP NGN. These include providing all kinds of services over all kinds of media, de-coupling services from networks so that a service is not defined by or limited to a particular type of network.

These NGNs also have open interfaces that offer flexibility to service providers, generalised mobility enabling end-user access to services wherever they may be, and, most importantly, providing end-to-end QoS. Service providers have different names for this concept. AT&T calls it ‘Concept of One, Concept of Zero,’ while British Telecom characterises NGN as the ‘21st Century Network.’

"Traditional services are under intense price pressure, and newer services will not have immunity from them for long" - Shrikant Shitole Business Development Manager Service Provider Cisco Systems India & Saarc

Says Prasad Babu, Head, Systems Engineering, India & Saarc, Juniper Networks, “NGN infrastructure permits the convergence of all applications and services on to a single infrastructure with the necessary QoS and bandwidth for each service with guaranteed service levels.” To this adds Shrikant Shitole, Business Development Manager, Service Provider, Cisco Systems India & Saarc: “The NGN architecture allows de-coupling the network’s transport and service layers. This means that whenever providers want to enable a new service, they can do so by defining it directly at the service layer without considering the transport layer. i.e. services are independent of transport details. IP allows NGN to integrate with the existing network infrastructure and transform it.”

Three levels

As mentioned earlier, IP is the foundation on which NGN is based. Convergence in IP NGN happens at three levels—application level, network level and service level.

At the application layer, carriers can integrate data, voice and video applications over a single broadband infrastructure. Application convergence opens the doors to all media services such as video-conferencing, which is effectively a new service integrating all the three basic ones i.e. data, voice and video. Other value-added services can also be delivered over any broadband connection. Babu explains that NGN creates application-level awareness in the infrastructure, which acquires the ‘intelligence’ to allocate as much bandwidth as is required by the user and bill the subscriber accordingly.

IP NGN allows end-users to avail of services from any access network. A user can utilise the same service in office, over a wireless LAN, a broadband connection, or a cellular network. These access networks have the ability to transfer the service and the state of the connection as the user roams, providing seamless connectivity.

In addition to applications and services, many carriers are already moving towards creating a converged network to eliminate the need to maintain several service-specific networks or to reduce multiple layers within a network. This ‘many services, one network’ model in which a single network can support all existing and new services will dramatically reduce the total cost of ownership for service providers.

With respect to the implementation of NGN Shitole comments, “Service providers will prioritise the layers of convergence in different ways. For instance, mobile operators focus on service convergence whereas cable operators target their efforts at application convergence so they can deliver video, data and voice services over a single connection. Service providers need to raise revenues and profits while reducing the cost of service delivery to create sustainable profitability. They can do this by offering services that are increasingly customer-centric; this demands a planned evolution to transform the network into an intelligent infrastructure.”

A question arises. What about the networks that are already in place? NGNs can be integrated with existing legacy systems, as Mallikarjun Rao, Director, Wireless Solutions, Nortel India explains. “Even though NGN provides multiple services through multiple bearers, interfaces in NGN are backward-compatible with the time-division multiplexing (TDM) infrastructure, hence it seamlessly integrates with a legacy system. It is not about replacing the legacy systems with NGN, but it is adding NGN to the legacy systems.”

Early days yet

Though none of the vendors have any customer yet for NGN in India, they believe that the advantages NGN offers are amazing. For the enterprise, NGN delivers a host of new services. These include high-speed data services, voice over broadband, video services like broadcast TV, video on demand, longer term video telephony, three-play services over mobility, and business services such as Layer 2 & 3 VPNs.

For service providers (SPs), NGN will offer new value-added services for top-line revenue growth, greater competitive differentiation, and increased customer loyalty. It will also help them regain control of networks and the services that run on them to have greater control over the business.

Remarks Babu, “NGN provides efficiency in network and 20-30 percent savings in transmission. SPs will also save on operating expenditure and capital expenditure. Users get multiple services at low prices, while multiple service providers save on the cost of talk.”

Shitole thinks that “traditional services are under intense price pressure, and newer services will not have immunity from them for long. Service providers need to build a more flexible, lasting and economical infrastructure that will both support existing services and support new and much richer services over time.”

Barriers to overcome

Before moving to NGN, each SP needs to ensure that it has a very clear set of objectives which it is trying to target with the NGN. This will include clear definition of the target market space, understanding the demand for services, clear understanding of the traffic flow and services mix in the network, carefully thought-out planning of phases of the NGN, and a very clear transition plan from the existing network to NGN. NGN deployment will require significant investment of planning resources, capital and operational resources.

Shitole throws some light on the regulation issues related to NGN. “There are a few regulation challenges such as VoIP in closed user group (CUG) and 3G spectrum that need to be addressed. VoIP is currently only allowed in a CUG environment but not in the PSTN environment. This results in companies investing and running two separate voice networks. Also, there is no clarity with regard to 3G spectrum allocation; this is delaying the roll-out of 3G services, and, in turn, delaying service-level convergence and the related application portability benefits for enterprises.”

However, the good news is that the Telecom Regulatory Authority of India has taken the initial step in defining an NGN framework for India, and has invited comments from the industry on defining NGN in the local context.

Apart from regulations, quality and reliability of service by the service providers is another issue. “QoS canbe implemented at a per subscriber level or a per service level. It can also be implemented at different points in the network from the home customer premise equipment to the digital subscriber line access multiplexer or the aggregation device,” explains Shitole.

Through NGN, next generation service providers will have a range of new possibilities for revenue and portfolio differentiation. This kind of service agility, as promised by vendors, is sure to create a stronger relationship between the carrier and end-user and can help increase customer retention.