FEATURE: Many Networks, One Subscriber -- Laying the Groundwork for Converged Services

Many Networks, One Subscriber -- Laying the Groundwork for Converged Services
Bridgewater System's Russ Freen explains how to leverage policy management to create dynamic, real-time service personalization.

Much as Nicholas Copernicus shook things up with the discovery that the sun, not the Earth, is the center of the solar system, network convergence shifts the center of service provider operations from the network to the subscriber.

Current service provider operations are built around specific infrastructure, allowing subscribers to access DSL services over DSL, 3G services over 3G and so on. With network convergence, the subscriber rises above individual access infrastructure to link with any service. This portability allows them to carry a single service regardless of the means they choose for access. In this case, the notion of 'DSL' or '3G' services ceases to be relevant.

To participate in the network convergence solar system, service provider operations must evolve to revolve around the new gravitational center: the subscriber.

One Subscriber, Many Services
The first requirement of subscriber-centric operations is a single repository of user profiles. This repository spells out the user's permissions to access networks and applications. It also serves as a single point of user management and provisioning.

Only with a converged view of the subscriber can the operator gain visibility to the subscriber regardless of access and link them to their personalized services. An architecture that enables applications to access the unified subscriber profile will simplify the application integration process and result in significant cost savings and reduced deployment times for service providers.

Subscriber interests are fickle. Therefore, service providers require the ability to launch services quickly and cost-effectively, using a common framework. The enterprise subscriber may expect to enhance an ongoing conversation with an important client, adding video or file sharing to the phone call as they move from the street to a high-speed hotspot at the airport. They may also expect to access a given application at X speed or quality of service (QoS) over their mobile phone and then access the same application at Y speed or QoS over a Wi-Fi connected laptop computer.

In the converged universe, subscribers will enjoy multiplied agility in using the services they desire on their own terms. The converged access subscriber can experience applications in a synchronized state, whether on a mobile or fixed network-connected device. They can continue work in a cab that began in the office.

In equal measure, service providers will enjoy new power and flexibility to respond to more varied customer demands with a greater variety of services and pricing schemes tailored to the subscriber.

Simplified User-Service Correlation
With convergence architectures like IP Multimedia Subsystem (IMS), opportunities multiply for development of advanced applications that generate additional revenue and differentiate services.

For example, an enterprise CIO may wish to give anytime, anywhere mobile roaming to sales people but not to administrative staff. Or Mom may wish to limit her teenager's data download traffic over the course of each month.

Such agility assumes that specific services must be correlated to specific subscribers in real-time as they log on to networks.

Historically, simple access to the network has been the function of traditional Authentication, Authorization and Accounting (AAA) systems. However, subscriber-centric operations require mechanisms to carry per-subscriber service policies-including roaming permissions, quality of service (QoS) settings, time-of-day permissions, data download thresholds and the like-across multiple networks owned and not owned by the provider.

This suggests that more must be done than simply look up subscriber authentication data to authorize network access. The AAA server becomes the logical nexus for the subscriber's personalized services and correlating that data with the subscriber logging in. This correlation then makes it possible to allocate network bandwidth and other resources on a per-subscriber, per-application basis.

Subscriber-Centric Policy Management
Real-time, dynamic control of personalized services requires policy decisions and policy enforcement. The subscriber profile becomes the center of not only authentication and authorization, but also for provisioning of personalized services to each of up to millions of unique subscribers.

Such a volume of policy decisions requires automation through a subscriber-centric policy management system. In other words, correlating subscriber to application is not enough; the process also must include a look-up of policies about each application. Only then can the proper resources be allocated to deliver the appropriate service to each subscriber.

The service provider can create differentiated services and service tiers by defining and automating service access and resource allocation policies at a granular level according to a wide range of variables, including subscriber, time, geography, bandwidth/QoS level, up-sell service trial, usage limits, or other parameters.

Even before IMS technology availability, applications like PTT, MMS and broadcast video can launch the era of subscriber-centric, policy-based delivery of converged services.

Dynamic Policy-based Provisioning
If the subscriber profile now stands at the center of the services solar system, policy could be compared to its force of gravity. Policy exerts control over routers, applications servers, deep packet inspectors and other pieces of the infrastructure to deliver the appropriate service to the appropriate subscriber.

The subscriber-centric policy system is rules defined by the service provider. If a Silver Service Tier user is allowed X bandwidth or full screen video, these rules reside in a single policy repository. The policy manager applies the rules to each authenticated subscriber and each service tier, reaching out to touch multiple components of the network that fall within the policy.

In line with putting the subscriber in charge, the policy management system also can be exposed to the subscriber. Via Web portal capability, the subscriber can look at and make changes in their account, selecting to graduate to the Gold Service Tier, for example, or clicking a 'turbo button' to take the Gold Tier for two hours, long enough to play a hot new online game.

Of course many policy decisions of this kind translate to specific line items in the bill. A subscriber-centric policy management system worth its salt will record the decisions and provide a standards-based interface to share them with mediation and billing systems.

The subscriber is succeeding the network at the center of service provider operations.

Subscriber-centric management of resources with granularity and real-time execution enables greater service differentiation and subscriber agility. Easier usage begets more usage. Empowering the subscriber to easily use personalized services adds up to service differentiation and revenue growth.

Service providers can begin preparing the way for this business imperative now by building a subscriber-centric policy management system. The fruits of this endeavor will include making converged services irresistible to subscribers and easily managed for service providers.

Russ Freen is Chief Technology Officer for Bridgewater Systems.