Deep Packet Inspection in PCEF Systems

By Charlie Ashton, VP of Marketing for 6WIND



This week, 6WIND joins Qosmos, RadiSys and Tilera in the Network Intelligence Alliance booth at Broadband World Forum in Paris. Both Deep Packet Inspection (DPI) and broadband network infrastructure are major topics of discussion at this event, so it seemed appropriate to share some thoughts on one of the major applications of DPI in 4G networks, as seen by us in our role as a provider of packet processing solutions.


The advent of 4G networks has raised the bar to the point where users expect to have constant access to advanced multimedia services, delivered via smartphones, tablets or laptops, regardless of their location. Subscribers who select premium rate plans rather than “best-effort” options expect to receive an experience commensurate with the higher costs. Streaming video should be a TV-like experience. Operators are required to provide a wide range of enhanced services to a fast-growing subscriber base, while delivering more traffic per subscriber, supporting more applications and offering an ever-expanding of client devices with advanced capabilities.


Network operators, on the other hand, face an on-going challenge to maximize their Average Revenue per User (ARPU) to offset constant increases in CAPEX and OPEX caused by investments in network capacity expansion and the adoption of advanced services. “Network Intelligence” is one key to maximizing ARPU: if the operator has real-time knowledge about the traffic characteristics and demand in their network, segmented by application, by user and by time-of-day, then they can deliver customized services that provide high value to specific customers. In addition, real-time application-level analysis of network traffic, including advanced heuristics or pattern recognition, allows operators to defend their networks against ever more sophisticated security threats and attacks.


DPI technology provides a solution both to the subscriber expectations outlined above and the operators’ needs to maximize ARPU. DPI-based networking equipment looks deep into a packet’s payload in order to classify traffic flows based on their application, as well as to capture appropriate application-specific content from those flows. Once the equipment has access to that information about the application and the content, it can perform networking functions such as forwarding, security, usage analysis, traffic management, resource allocation, QoS and billing.


The “network intelligence” provided by DPI enables these functions to be performed with much more sophistication than in traditional networking equipment where decisions are based only on the packet header. Operators now have access to a wealth of information as a result of data mining, profiling and analytics, all of which are key to the creation of personalized service packages based on a deeper understanding of customers’ needs.


Within a 4G wireless network, Policy and Charging control (PCC) functions provide operators with advanced tools for service-aware Quality-of-Service (QoS) and charging control. Within the network, the Policy and Charging Enforcement Function (PCEF) identifies and associates applications and/or users with specific traffic flows, applying policies to individual sessions based on requirements defined by a network element called the Policy and Charging Rules Function (PCRF).


Architecturally, PCEF is part of the PCC function defined as part of 3GPP specifications. PCEF interfaces with the Packet Data Network Gateway (PGW) and with the PCRF. Physically, it can be implemented either as a dedicated blade, or integrated into the PCRF, or as a co-located but separate appliance. Regardless of the actual implementation, however, the advanced DPI functions required for PCEF place significant performance stress on the underlying processor platform, due to the real-time processing bandwidth required to evaluate and act on sophisticated heuristics or generate advanced billing information.


6WIND and Qosmos have partnered to provide an integrated solution that addresses these challenges. With tight integration between the companies’ products, network equipment providers can add Qosmos’ real-time Network Intelligence capabilities and 6WIND’s advanced, multicore packet acceleration to their solutions, benefitting from proven interoperability between the two complementary technologies. This accelerates time to market for advanced mobile, cyber security and network applications.