CAPE TOWN At Cape Town's Elswood Secondary School, even the metal grills welded into its walls did not deter burglars from ripping out the copper cables that delivered Internet to the students of this tough neighbourhood.
But Elswood's pupils were saved by alternative technology - free wireless connection via unused parts of the TV spectrum known as white space. It's being provided by a consortium led by Google as part of a wider trial. Elsewhere in the country Microsoft is operating similar pilots. Both are racing to fine tune a technology that could ultimately bring cheap broadband to the entire continent.
"Using white spaces will definitely be a more cost effective way to take Internet to the masses," said Spiwe Chireka, an analyst at research firm IDC.
Africa is the world's last major untapped market for Internet access. Only 16 percent of its billion people use the Internet - half the penetration rate of Asia, according to the International Telecommunication Union.
Most Africans who can access the Internet do so via mobile phones because few have the landlines that have been the means of connecting in Western countries. This has pushed broadband usage to 11 percent this year from just 2 percent in 2010. But mobile phone companies are reluctant to build costly masts and networks in remote rural areas - meaning hundreds of millions of Africans have little prospect of ever going online.
Google and Microsoft are chasing this massive new market, aiming to provide white space Internet access to rural swathes with no coverage and in megacities where overcrowding and built up areas can mean frustratingly poor phone reception.
Africa's thinly populated airwaves - Zimbabwe, for instance, has only one TV station - make it ideal for this technology because of the abundance of available spectrum. Microsoft is running pilot schemes in Kenya, Tanzania and South Africa with the aim of launching commercial projects thereafter. Google is sponsoring trials in schools, including Elswood, across South Africa.
While for both firms the logic of developing cheaper ways to access new customers is clear, the incentive for governments is also compelling. World Bank research shows that a 10 percent increase in broadband penetration can result in an extra 1.4 percentage points of annual economic growth.
"This is really welcome," said Patrick Muinda, a spokesman at Uganda's education ministry. "We need as much bandwidth as we can get. More children are being taught computer studies as a subject and more computers are being purchased for use on e-learning platforms. This would just hasten that process."
HOW IT WORKS
Television networks leave idle gaps between channels in order to protect themselves from interference from other networks. The technology uses these "white spaces" to transmit and receive wireless data signals.
The adapted TV radio waves can travel up to a 10-kilometre radius, making them ideal for connecting off-grid villages. They penetrate walls better than mobile signals. And they're cheap to provide: building a white spaces mast costs a tenth of the amount needed for a normal telecoms base station, said Arno Hart, project manager for the Cape Town white spaces trial being funded by Google.
"It's a great medium for ... wifi hotspots anywhere, so that any population or demographic profile can have access to good affordable Internet," Hart said.
Local Internet service providers are helping: In Tanzania Microsoft has partnered with UhuruOne to provide connection to students at the University of Dar es Salaam. In January the project will be expanded to four universities, giving more than 72,000 students broadband access for $5 a month.
In Kenya, Indigo Telecom and the United States Agency for International Development are working with Microsoft to provide wireless broadband to rural schools, a health clinic and government office in remote areas of the Rift Valley province.
Indigo is currently providing free Internet to schools but plans to charge those living in the surrounding community $1.50 per month for connectivity in future. It has provided the infrastructure - fibre, masts and radios - while Microsoft supplies the software and applications.
"We've started in areas that economically are not viable for mobile phone companies to start in," said Indigo's chairman Peter Henderson. "The strength of our operation is low cost of connectivity that lends itself to the areas that previously would digitally have been forgotten."
Vodacom, South Africa's biggest mobile phone company, said it was following the technology closely.
"It's an interesting initiative. At this stage it's not clear how it will be managed from a regulatory perspective, so it's difficult to speculate on how it may impact the overall provision of connectivity," spokesman Richard Boorman said.
Governments have largely welcomed the technology though some officials have expressed reservations about whether it could affect or cross into bandwidth reserved for the military, emergency services and air traffic control.
African regulators are also watching closely to allay concerns that broadcasters could be affected by interference, said Whitney Cubbison, communications director for Microsoft's Africa initiatives.
One country, which Microsoft declined to name, has warned that the process to change its regulations could take another couple of years.
Google's Cape Town trial is backed by the South African regulator, which is using the test case as the basis of future regulation, and has said Google can continue the project past its original September end-date.
Regulators in Malawi and Senegal, countries with only a handful of broadcasters and plenty of available spectrum, have also expressed keen interest in the technology, Google said.
Microsoft says it is in talks with 10 more African governments to start trials but will not say which ones or how much the tests will cost.
"At this point, we feel there is ample proof that white space radios can coexist with incumbent licensees without any risk of interference," Cubbison said.
Back in Cape Town, schools participating in the trials hope everything works out. They are keen to hang on to their new, faster and more reliant Internet.
"We don't mind paying for it because it works for us," said Paul Haupt, head of IT at The Settlers High School, a more affluent school in the Cape Town trial. "We've gotten used to a good service."
Tyler Jacobs, an Elswood 10th grader working on his homework during a break in a packed computer room, summed it up: "It makes life so much easier."
(Editing by Sophie Walker)
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