Mobile data consumption continues to grow rapidly, largely driven by smartphones and tablets. This has resulted in the introduction of so-called Long Term Evolution (LTE) mobile technologies, better known to the public as 4G and eventually 5G mobile network. These LTE technologies boost the availability of maximum capacity, which is needed to support the demand from individual mobile cells, further boosting the mobile broadband traffic explosion.
The emerging Internet of Things presents another vast challenge to mobile networks, that will need to backhaul vast amounts of data. Furthermore, the need for a more ‘granular’ approach and resulting evolution towards ‘small’ cell architecture configurations is expected to redefine the backhaul need for mobile networks.
Mobile communication today requires far more bandwidth than current infrastructure is capable of providing. FTTH, however, can help rapidly move data between mobile and fixed networks. According to a study by the Fibre to the Home Council Europe, using fibre for this ‘mobile backhaul’ is becoming the norm in advanced mobile networks.
Guaranteeing access
“Our position on fibre for mobile backhaul is very straightforward,” states FTTH Council Europe President Edgar Aker. “We see FTTH Networks and wireless networks being complementary, not as competing. A mobile network without strong fibre support - and fibre backhauling - simply can’t meet today’s needs.”
“An often-heard argument against rolling out fibre is the claim that wireless is cheaper and nobody needs a connection faster than 100 Mb/s today. That sounds convincing – as long as you forget wireless is a shared medium! One good example is the situation in Germany, where the companies that had first obtained LTE frequencies were obliged to roll out in rural areas first. That led to celebrating amongst the inhabitants of villages and small towns who would finally have access to 100 Mb/s. However, once dozens, even hundreds of people actually started to subscribe to a single LTE base station, everyone’s bandwidth plummeted. After all, if 20 customers have to share 100 Mb/s, nobody will get more than 5 Mb/s. Hardly future-proof or ‘next generation’ access! To ensure all people to have enough bandwidth the wireless link needs to offload its data to a wired infrastructure within a short distance. To guarantee sufficient mobile bandwidth, you simply need a lot of high-speed - preferable symmetrical and low latency - fixed connections feeding the mobile LTE base stations. The people in Rural Germany will then get the promised 100MB/s or – with 5G potentially – even more. Regional fibre penetration will increase as a result of such a customer experience.”
Changing network requirements
“In 2013, the FTTH Council Europe carried out a study with IDATE, who concluded that LTE and wireless activities are real drivers for FTTH. Deployment of fibre into 4G/5G Mobile base stations will require deep fibre penetration, in the range of 500m max, and this will only support the business case for installing Fibre-to-the-Home. Especially in Urban and Suburban areas, population density requires every building to be connected with a fibre (FTTB) to provide enough mobile coverage. For rural areas, we think fibre is the only serious future-proof solution for getting next generation broadband into peoples’ homes. There is no way a single wireless solution could do this – the bandwidth simply isn’t there. In recent years, user habits and related requirements have changed from being satisfied with one fairly low-bandwidth connection at home, to expecting to seamlessly stream 4k or 8k video to multiple devices. Doing this with a fully wireless solution would mean enormous bottlenecks, especially when people are sharing the medium. The prime bottleneck is the mobile backhaul, offloading the data and bandwidth to a fixed infrastructure. People – wherever they live - are now used to the idea of mobile working, which also changes network requirements. Mobile in this sense also means WiFi-connection inside the home or office, offloading data rapidly to a FTTH network.”
“When wireless operator Turkcell’s subsidiary Superonline started planning its LTE network in Turkey’s larger cities, they discovered that installing base stations on buildings would require a lot of fibre. So, they thought, why not take that fibre straight to the end user? Superonline is now one of the biggest and fastest-growing fibre operators in the greater European region. Last Spring, their CEO told me they had 700,000 customers– none of whom had cancelled their mobile phone subscription.”
“According to the IDATE study, Femtocells and even smaller Picocells will be a critical part of LTE network deployments. These small, low-cost, low-power base stations are generally employed in residential or business environments where they improve the indoor signal. Given the issues in urban areas and the poor indoor penetration of high frequency LTE (2.6 GHz), LTE femtocells can improve the performance of service provider networks.”
Mutually supportive
“Many experts are aware of the need for fibre for mobile traffic offload, but decision makers don’t always share this sense of urgency. At the moment, many governments and stakeholders are insufficiently aware of the need for fibre in mobile networks. What’s more, many mobile operators don’t want to create too much awareness for fibre, as they can use their infrastructure to provide internet connections to users outside the urban areas. Positioning themselves as an alternative to broadband, could give them access to public money. Last year, Austrian operators had to pay 2 billion Euros for LTE frequencies, even though Austria is not a very large market. If an operator has to pay that kind of money, they will definitely try to claim a share of public funds meant for broadband - which we think would be better spent on FTTH.”
“We expect to see increasing convergence between fibre and mobile. One new European network has already announced it will incorporate enough dark fibre to accommodate mobile operators’ future LTE and 5G rollouts. Lower Austria’s fibre network plan for rural towns and villages also discusses making the network directly available to mobile operators. In the view of the FTTH Council Europe, mobile and fibre rollouts are mutually supportive.”
Given the high capacity potential of optical fibre, using FTTH appears to be one of the best technical solutions for mobile backhaul. Today, operators tend to choose GPON, as it is the configuration delivering higher bandwidth. FTTx & FTTH networks are currently being deployed by significant carriers such as AT&T, Verizon, Cox and TeliaSonera for their LTE network backhaul. Most cell sites are fibre-fed in metropolitan areas in China, Japan and Korea. NTT DoCoMo and China Mobile are massively deploying fibre to backhaul their sites.
SOURCE: FTTH Council Europe Webinar “FTTH: THE Solution for Mobile Broadband? Focus on Europe.”
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