Mobile operators around the world are feeling the strain as tremendous growth in data traffic swamps their networks. American, European and Chinese operators have withdrawn some of their unlimited data plans because they are unprofitable.
Just how this additional load affects the customer experience is difficult to pin down. The divergence in data consumption between heavy and light users is dramatic. AT&T’s CEO Ralph de Vega explained that around 2 percent of their users consume 41 percent of total data usage, leading him to indicate that tiered pricing could be a likely outcome. Other service providers validate these figures.
It’s not just straightforward data usage that’s the problem. Many smartphone applications actively perform frequent status checks, leading to congestion of the signaling channels and the core network. The result can be missed voice calls or poor coverage in many areas.
There are many ways of dealing with this issue, and we outline 10 different methods that could be used in different measures by operators in the next few years.
1. Expand existing cellsite capacity
Cellsite capacity can be expanded in several ways with additional hardware. More recent equipment can be software upgraded to the latest high speed version, known as HSPA+, which provides additional capacity as well as higher peak data rates.
This measure should not be confused with the various RAN sharing activities in progress in many countries. RAN sharing saves costs by reducing duplication of cellsites by two or more operators. It doesn’t by itself increase capacity.
2. Roll out LTE
The upcoming 4th Generation radio technology, Long Term Evolution (LTE), promises greater spectral efficiency and higher data rates than its predecessors. In the long term, this should lead to lower costs because it requires fewer cellsites to deliver the same payload.
In many countries, the spectrum to be used is not yet available and will have to be cleared. Spectrum may be expensive to buy. A wide range of supported devices is unlikely to become available until 2013 at the earliest.
3. Buy More Spectrum
In many countries this won’t be an option, but some governments are continuing to make new spectrum available. India has only recently auctioned 3G spectrum for the first time. The digital TV spectrum freed up across the U.S. and Europe releases attractive new frequencies for this purpose.
4. Offload data to Wi-Fi and Femtocells
By encouraging use of Wi-Fi hotspots at home and suitable indoor areas, operators can significantly remove a large proportion of data traffic from their networks. 3G signals at the common 2.1GHz frequency are poor at penetrating indoors, further enhancing the value of this approach.
Femtocells are miniature 3G cellsites, very similar to Wi-Fi hotspots, installed by consumers in their homes and connected using wireline broadband. Many operators are trialling or launching femtocell services with a view to solving both coverage and capacity problems.
5. Metro-Femto
The metro-femto concept, first outlined by Kenny Graham, head of new technologies and innovation at Vodafone, follows on from the domestic femtocell/Wi-Fi concept above. Large numbers of low-cost cellsites are installed in high data traffic areas, such as transport hubs, stadiums and city centers.
One approach involves hanging these from existing street wiring, or they can be integrated with street furniture. Due to their small size, these unobtrusive devices do not attract the same ire of large cell towers bristling with antenna.
6. Sideload
Anyone familiar with Apple’s iPod or iPhone will be aware of how it downloads content to a PC or Mac and transfers it across without going through the mobile network. Podcasts, music and films can easily be bought and updated.
This technique can be used for content bought on mobile devices too – for example, the shopping transaction could still be carried out over the air, but larger data files transferred by computer or through your home Wi-Fi or femtocell.
7. Traffic Shaping
This technique shares available bandwidth in a more balanced and even-handed way so that everyone gets a reasonable service at all times. This means that large file transfers or heavy video streaming sessions may be affected at peak times.
Traffic shaping commonly uses Deep Packet Inspection (DPI) within the core network to monitor and analyze each individual data session. It is also appropriate to use admission control at each cellsite to avoid individual users saturating the local capacity.
8. Data Pricing
Many networks today offer unlimited data usage and have suffered the consequences. Others have very high limits, such as Austria Mobilkom’s 19GB for a 19 Euro monthly tariff. We have seen many more networks introduce monthly caps on their data plans to address this.
An important factor here concerns education of the customer so that the meaning of data tariffs is fully understood.
Approaches to be considered include charging premium or blocking some types of data traffic such as streaming video, which places high demands on network resources.
9. Optimize/Compress data content
With video taking up a large proportion of mobile network data capacity, it makes sense to reduce the amount sent. Wastage can be avoided by preventing advanced download of buffered video that isn’t watched, or transcoding large screen high resolution video formats.
10. Improve Application Design
A more subtle form of data optimization involves encouraging and persuading application developers to write better behaved software. Many free and commercial applications are not written with due consideration of their impact on network resources. A program of education and encouragement might be further enhanced by rating applications based on their behavior. There would also be knock on effects of improved battery life and response time for the consumer.
Summary
Mobile network capacity management is a complex issue with many alternative approaches to be considered. Financial success awaits those operators who take a holistic approach, investing in the right tools and strategies to anticipate and meet their customers’ needs profitably.
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