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Cool-Tether turns phones into high-speed hotspots

Nokia E75

By Barry Collins

Posted on 1 Dec 2009 at 09:49

Microsoft Research has found a novel way of beating the deplorably slow speeds of mobile broadband, by combining several phones together to make one high-speed hotspot.

Dubbed Cool-Tether, the system harnesses the mobile data connection of multiple mobile handsets to build an on-the-fly Wi-Fi hotspot.

It's not the first time Microsoft's unveiled the concept: a 2007 research project called Combine suggested a similar means of tapping the bandwidth of several handsets.

However, Combine proved too power hungry, because even when a phone was only asked to transfer a small chunk of data it remained in a high-power state for several seconds afterwards, quickly draining the smartphone's battery.

Cool-Tether alleviates that problem by calling on fewer phones to deliver longer bursts of data, maximising the amount of data delivered in those battery-draining sessions.

"To address the challenges of energy efficiency, Cool-Tether carefully optimises the energy drain of the WAN (GPRS/EDGE/3G) and Wi-Fi radios on smartphones," Microsoft's research paper claims.

"We prototype Cool-Tether on smartphones and, experimentally, demonstrate savings in energy consumption between 38%-71% compared to prior energy-agnostic solutions."

The system is most likely to be harnessed in developing nations such as India, where mobile internet is far more prevalent than fixed-line access.

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User comments

Nice idea but...

One annoying trend that's messed up my tethering experience lately has been the way that phone companies in london have clubbed together, doing their own version of "combine" so that they can have several networks all sharing a single base station. This went so well that O2 were obliged to advise iPhone customers to turn off 3G mode... so if you have a desk-full of phones, the chances are that they will all share one base station's capacity - even if they are on different networks.

By Steve_Cassidy on 2 Dec 2009


Although 5 phones may be using the same base station for their connection, they will only have a limited amount of data each can download, where as if those connections are shared to one source (laptop/mobile) the download speed will be larger.

By Carter89uk on 2 Dec 2009

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