This is a short article on a relative “old” architecture, from the standardization point of view, but not yet fully used on top of its capabilities by the established MNOs (Mobile Network Operators).
3GPP Policy Control and Charging (PCC) architecture is an evolutionary not a revolutionary one. When it was proposed, their functions split off existing mobile IN (Intelligent Network, aka CAMEL) functions, translated from switch (voice) to packet domain.
The main architectural control elements specified are PCRF (Policy and Charging Rules Function) – for police control (a lot more than only QoS) – and OCS (Online Charging System) – for charging control. Since its first release, it is ones core network architecture with more updates over the last decade, and still work in progress.
Driving New Services
Over the past years most vendors describe bunch of possible business cases to validate the heavy investment on network capabilities to support all newly policy functions. However, the evolving part of the architecture plays its role and most of new products launched were focused on online charging services, with pre-paid data plans potentials and variations being a must.
Abstracting the architecture and thinking about policy user cases, we realize that a lot of business cases didn’t come to light due to enough support on legacy packet network elements and even on standards (one reason for too many spec upgrades) and regulatory issues.
On the network side, the capability to detect and inform the correct user traffic and application were main bottleneck that 3GPP specification try to address, e.g. with the TDF (Traffic Detection Function). A great number of business models can be explored at this configuration, but it’ll require a new network element (or new capabilities on existing ones), and new interface to PCRF. Virtualization (SDN and NFV) can play a role here, easing new capabilities adoption and deployment.
On the northbound side, the 3GPP standards are less restrictive, and the MNOs should decide how easy would be integration of new services , by defining a good APIs set to expose those policy control and charging capabilities (see my previous article on online charging future here). Vendors support in providing an open and fully configurable application interface is mandatory for MNOs willing to explore those capabilities.
On the regulatory side, the policy control services face a great pressure from net neutrality rules on some markets. Less net neutrality should drive new services models, but its still unclear how deep political changes as seen with Trump’s election and Brexit will affect the current regulatory direction.
As policy and online charging services are a cornerstone on MNOs market, the 5G ongoing discussion on core network architecture will certain drive another evolution round on PCC architecture, after VNF introduction as well.
Also IoT mass deployment will demand a strong policy control and differentiate charging from MVOs, something hard to achieve without a standard architecture.
Mindset Changing and Next Steps
As conclusion, the Policy and Charging Control architecture are a powerful technology for service differentiation. Though, a key paradigm on MNOs business systems must change.
Policy and Charging architecture should be understood as the lower end of the Operator’s service creation chain and not as core network elements. PCRF and OCS are better described as service platforms and service enablers’ functions, but they’ll add value only when tied on Operator’s service layer business process.
Operators’ online policy and charging capabilities must also be securely exposed to internal and external service partners to be able to fulfill the business models predicted by the industry.