Alcatel-Lucent Breaks Record with 31Tbps Over a Single Fibre Optic Cable

Global telecoms giant Alcatel-Lucent claims to have set a new world record after it successfully transmitted information (data) at the staggering speed of 31Tbps (Terabits per second) over a single long-haul 7200km optical fibre cable (i.e. simulating undersea transoceanic cable distances).

The experiment itself, which was carried out at by the firms R&D focused Bell Labs division on the Innovation City campus in Villarceaux (Paris), is understood to have used 155 lasers. Each laser was operating at different frequencies and carrying 200Gbps of data (single-carrier data channels) over a 50GHz frequency grid.

Normally such signals suffer from distortions and noise, which limit performance, but it’s understood that Alcatel-Lucent were able to resolve this by using an enhanced version of Wavelength Division Multiplexing (WDM) that works by splitting light up into different wavelengths so that it can carry more data (a variety of other methods were also used).

Philippe Keryer, AL’s Chief Strategy and Innovation Officer, said:

“Undersea fiber-optic transmission is integral to the digital economy, delivering vast amounts of video and data between countries, regions and continents. As our customers cope with increasing demand on their networks for data capacity and higher-speeds of transmission, our researchers are intensifying their application with tests like this to develop new technology solutions to transform global data networks. This underlines the strategic R&D focus we recently announced as part of The Shift Plan.”

The pace of development in this field has been startling and it’s easy to see just how far we’ve come by taking a quick look at some of the other recent developments. Back in May 2011 a team of German, UK and Swiss scientists successfully used Orthogonal Frequency-Division Multiplexing (OFDM) to send data at a rate of 26Tbps over a 50km long single-mode fibre optic cable (here).

Then in January 2012 a Japanese team working out of NEC successfully transmitted 4Tbps over a single “ultra-long haul” (10,000km) fibre optic cable (no repeaters) by making use of WDM just like Alcatel-Lucent (here). Lest we not forget all the other developments, such as the successful UK test of a new type of hollow fibre optic cable that earlier this year delivered speeds of 73.7 Tbps (here).

Alcatel-Lucent might have just set a new record and one that it is arguably most notable for its distance but such records are clearly made to be broken. GCHQ will probably get a headache if they want to “tap” (spy) on the next generation of transoceanic cables.