Original URL: http://www.theregister.co.uk/2012/03/07/deutsche_telekom_data_record/

Deutsche Telekom shatters data-transfer speed record

734 kilometers, one second, 77 CDs

By Rik Myslewski

Posted in Data Networking, 7th March 2012 00:29 GMT

Researchers at Deutsche Telekom's T-Labs have blasted bits at impressive velocity down a single optical fiber, breaking the previous long-distance data-transfer record by more than a factor of two.

The bit boffins achieved a 512 gigabits-per-second transmission rate over a single optical fiber from Berlin to Hanover and back, a distance of 734 kilometers. Subtracting out the error-correction overhead, the total usable bandwidth was 400Gb/s – enough, T-labs points out, to transmit a stream of data equivalent to 77 music CDs in one second.

Just last December, a team of Canadian and US researchers managed to sustain a computer-to-computer data transfer of a combined 186Gb/s between the University of Victoria Computer Centre and the SuperComputing 2011 convention in Seattle – and that was a combined 88Gb/s in one direction and 98Gb/s in the other.

T-Labs popped all their bits down a single 100GHz fiber line at just over five bits per cycle.

"This tremendous transmission performance was reached using innovative transmission technology with two carrier frequencies, two polarization planes, 16-QAM quadrature amplitude modulation and digital offline signal processing for the equalization of fiber influences with soft-FEC forward error correction decoding in the receiver," T-Labs explains.

This new technology, they say, would enable a standard 48-channel, 100GHz optical-fiber transmission/reception setup to achieve a total throughput of 24.6 terabits per second. A quick bit of multiplication shows that system to be able to squirt 3,696 CDs-worth of data in one second.

There was no need to replace the fiber itself. As T-Labs notes, the channel was in place, and the modifications were made to the transmitters and receivers. As such, the improvements in data-transmission rates could be achieved without the expense of laying new fiber.

"We are very proud of having attained this tremendous transmission performance over the Internet under real-world conditions," said T-Labs manager Heinrich Arnold.

In The Reg's humble opinion, if these rates are stable, repeatable, and relatively easily and inexpensively deployable, Herr Arnold and his team have much to be proud of. ®