Smartphone and tablet usage is continuing on an impressive trajectory. More devices keep appearing, nipping at the heels of the market leaders, while useful software and tempting content swell the app stores.
All great stuff – unless perhaps you’re a mobile operator trying to keep services up and costs down, or a mobile user who has discovered what capacity crunch means.
But surely the new fourth-generation technology, LTE, will fix all these issues when it becomes more widely available in Europe? After all, it will provide tens of megabits of bandwidth in each direction. So, the solution is there in the near future, right?
Well, it may help, but even if it does, it will only be for a time. Despite more efficient use of the spectrum, LTE is still limited by the laws of physics. In congested areas with large numbers of people all trying to use their favourite shiny gadgets at the same time, services break down.
Later this year in the UK, London’s Olympic venues and perhaps even the entire city may provide further insights into what we might all experience in the future.
Tackling mobile bandwidth overload
The question is, what can operators do now? In reality, there are several aspects that can be addressed, and a number of vendors offering products aimed at tackling the issue. The problem is there is no single simple solution, and operators need a portfolio of tools, each working to extract the best service from each of the various pinch-points.
Since their approach should really be about ensuring the end-customer experience is the best it can be, operators should look both at symptoms and root causes, and along every part of the network from subscriber to the core.
Fundamentally, there are too many people, using too many network-hungry applications in places where the wireless edge of the network does not have capacity or where there are bottlenecks in the base stations, the backhaul or core networks.
- Dissuade usage
One way to address this root cause of too many people is to dissuade usage. On the face of it, this approach might not seem palatable, but it could be accomplished in many ways without using blunt instruments such as tariff price rises or usage caps. Operators could do more to create or promote alternative services that lessen the total demand, or introduce incentives for time and place shifting, along similar lines to the UK’s off-peak Economy 7 electricity tariffs.
- Assess efficiency of network elements
The next thing to look at is the efficiency of each of the existing network elements. First, the wireless edge, the radio link. Is the currently available spectrum being used as efficiently as possible? The radio footprint of each cell tower is generally well planned individually, but could other radio elements such as micro and femto cells be added to usage hotspots? Could more be done to look at how usage patterns change over the day and the cells and antennas more dynamically aligned to cope better?
- Offload traffic to Wi-Fi
If cellular usage is the issue, what about offloading to Wi-Fi? A good idea in theory, but in some highly congested areas, such as airport lounges, Wi-Fi networks are more overloaded than cellular ones. The lower cost, or at least more predictable, all-you-can-eat type pricing models win over a lot of Wi-Fi users, and the sudden influx of popular tablet devices only pushes this growth further, straining networks that have often been planned and deployed in an ad hoc way. While Wi-Fi has been becoming a more professionalised service, it needs to be properly managed as a carrier-style product to offer carrier-grade service. This philosophy is rarely put into practice.
- Better traffic management
However, offloading to other radio connections does little to ease the burden on the backhaul network. Here the simple solution might be buy or rent more fibre, but as demand on backhaul from a mobile data capacity crunch is likely to be peaky, getting hold of more total capacity might not be economical. Traffic management then comes to the fore. Does every bit have to be delivered with the same expediency?
It may seem slightly taboo to suggest it, but does the network need to treat all data equally? No. This is not about undermining net neutrality or democracy of access, but about efficiently shaping and throttling the flow of bits to ensure that live services flow when they need to, and other less time-critical ones can be buffered and delayed to ensure better flow.
Taking a view of network content at the application level allows traffic to be managed better and allows other tools to be brought to bear, such as caching, compression and content adaptation. Here the smart application of context – user, location, device, content – means that data can be intelligently filtered before it even hits the backhaul network.
This management does not all have to take place in the core either, as smarter mobile devices have the power and capacity to pre-process much more information and reduce their own impact on the network. At least they could if only mobile application developers were more aware of the precious network and its limitations, and were more or parsimonious with its resources.
Just like dealing with congested roads and highways, there is no single solution to congested mobile networks and simply building more is not always better. But there are plenty of options available. They just need to be used in a concerted and coordinated way to minimise perceived impact on subscribers and costs to carriers