By Dean Bubley, Disruptive Analysis
Summary: One of the most popular ways to deal with mobile broadband traffic growth is to “offload” it, typically to WiFi access points or femtocells. Also giving improvements in indoor coverage, these methods reduce load on the main macro-cellular network, cost of backhaul, and can also improve users’ experience in terms of speed.
However, the range of possible offload options is proliferating fast; they also involve a complex mix of control by operator, end-user, device and/or third-party service providers. This is generating a requirement for mobile broadband operators to be more intelligent and strategic in how, where and what traffic they divert to these alternative accesses. As operators develop their own IP-based data services, they may wish to treat these differently to bulk Internet downloads in terms of data routing. There is also a significant potential role for fixed and cable operators to run “managed offload” services on behalf of the mobile carriers. Understanding and managing offload effectively will be a key driver in future profitability and reliability of mobile broadband services.
Background
This white paper covers a number of issues around next-generation offload of mobile data network traffic to reduce load on operators‟ Radio Access Networks (RANs) and core networks, as well as the role of Deep Packet Inspection (DPI) systems in enabling this.
It has been written by the independent industry analyst and consulting firm Disruptive Analysis, and sponsored by Continuous Computing, as part of an initiative to promote thought-leadership, differentiation and innovative networking concepts for the mobile broadband and network policy-management marketplace. The opinions expressed are Disruptive Analysis’ own, and are not specific endorsements of any vendor’s or operator’s products or strategy.
Introduction- The emergence of the offload concept
The concept of mobile broadband offload first started to become a major theme in 2008. Disruptive Analysis and others noted that the bulk of mobile data on cellular networks was originated from, or destined for, the Internet, rather than the operator’s own services, and was therefore unnecessary to push through all the complex core network machinery rather than connect via a more direct and inexpensive route straight to the Internet.
Since then, an even more pressing concern has arisen: the need to offload the RAN because of heavy congestion from both the volume of network traffic and the associated signalling load from smartphones and their applications. Readers will no doubt be very familiar with the general data explosion / tsunami / capacity crunch stories, and the iconic scissors-style graphs of data volumes out-stripping growth in revenues.
Recently, a variety of offload solutions have emerged, mostly WiFi-based, and many intended for deployment with firefighting levels of urgency. Some of the early offload variants have been comparatively “clunky”, especially those involving user intervention to switch to WiFi, although improvements in connection manager software has made this somewhat more seamless. Longer-term and more elegant options are also now being proposed, notably with femtocells / small cells, Long Term Evolution (LTE) or later versions of the 3GPP standards, such as SIPTO (Selective IP Traffic Offload).
The general aim is to get as much of the low-value, bulk Internet traffic off the mobile operator‟s network as quickly and painlessly as possible, with the lowest cost, with the aim of reducing current congestion and delaying future capex for upgrades. And if elements of the cost or management of the infrastructure can be borne by someone else (e.g., the user themselves), then so much the better.
