Technology Update : Issue no. 3/2009

Convergent policy control

J. Javier Pastor

Policy control in telephone networks

Telephone networks have evolved from dedicated links (from an exchange to end users) to a common broadband network that is shared by a multitude of end users who must compete for quality of service.

In this new context, operators strive to provide a high-performance network that delivers highly rewarding multimedia experiences, encourages customer longevity, and supports market-differentiating services.

Policy control plays an important role in regulating this new reality. By applying policy control in their networks, operators can

• guarantee the bandwidth of higher-revenue services;
• allow market segmentation;
• assure fair usage of the network, thereby giving all end users the same access opportunities;
• stop or reduce services that retard network performance; and
• provide the best end-user experience.

Policies are enforced in the policy controller node, which is situated between the service and transport domains. This location enables operators to control the upper and lower domains by aligning service needs with transport network behavior. As a result, the transport domain can be configured to maximize the user experience. In other words, subscriber- and service-aware control enables operators to optimize network performance.

 

The way to convergence

Operators continually endeavor to minimize costs and network complexity. One outcome of these efforts was an audit or comparison of the fixed and mobile network domains in order to identify synergies as well as redundant functions. This work, in turn, led to the approach defined in 3GPP to employ a single core network to take care of several heterogeneous accesses.

Clearly, operators stand to benefit from this kind of convergence – in particular, those operators who manage both fixed and mobile networks. Vendor product offerings, for instance, will be much simpler, approaching a one-size-fits-all model. Likewise, operators will be able to use the same “box” to control fixed as well as mobile nodes. Convergence will thus yield better-optimized networks with simpler architectures and less need for maintenance.

Figure 1. The convergent lens

In addition, where policy control is concerned, operators will only need to configure a single box for the fixed and mobile domains, which means they can apply common and consistent policies to both networks. This, in turn, caters for real-life end-user movement from, say, the fixed network to the mobile network, seamlessly setting the stage for true multi-access networks.

The Ericsson solution
Ericsson’s product offerings have traditionally been divided into two categories: products for mobile networks and products for fixed networks. above.

Now, however, by making the most of the Redback acquisition and by drawing on solid experience of policy control in mobile networks, Ericsson can offer convergent policy control. The new convergent policy controller will be a major and valuable asset to service providers (fixed as well as mobile) who implement IP and broadband next-generation networks and service portfolios.

CONTRIBUTORS

Jose Javier Pastor joined Ericsson in 1998 and has worked in a variety of areas including design, system management and standardization. He has devoted the past five years to 3GPP standards that drive policy control architecture. He is currently responsible for releases of SAPC (Ericson’s policy controller). Javier holds an M.Sc. in telecommunications engineering from the Universidad of Valladolid, Spain.