December 3, 2004 Paris -- Alcatel, France Telecom, and Deutsche Telekom recently completed a successful field trial achieving a terabit per second transmission over an existing fiber link in France Telecom's network. This trial was conducted under the framework of the TOPRATE European research project, which began in 2001.
The goal of this research project is to investigate advanced ultra high channel bit-rate transmission technologies (170 Gbit/sec or more per channel) and to demonstrate terabit per second (1,000 gigabits per second) network transmission capacity over installed fiber infrastructure. The recent trial resulted in a point-to-point DWDM transmission of 1.28 Tbits/sec over a 430-km standard (ITU-T G.652) singlemode fiber link in France Telecom's network in the Marseille area.
Test results were achieved using eight densely packed optical transmission channels, each carrying a record bit rate of 170 Gbits/sec (160 Gbits/sec plus an overhead to allow bit error detection and correction). This channel bit rate is 16 times higher than the 10-Gbit/sec channel bit rate of current standard DWDM transmission products.
The TOPRATE field trial demonstrated that the severe sensitivity to transmission impairments associated with ultra-high channel bit rates can be managed over long distances and that traditional singlemode fiber -- the standard transmission medium in the networks of France Telecom and Deutsche Telekom -- is future proof with respect to a further increase of channel data rates.
Joëlle Gauthier, Alcatel's vice president, research and innovation, commented, " Research collaborations like TOPRATE are fruitful for Alcatel as they provide an opportunity to validate very advanced technologies, such as 160-Gbit/sec transmission, with field trials in our customer's networks. It accelerates technology maturation and allows us to integrate customer's needs at a very early stage in the development cycle."
Pascal Viginier, director of the R&D Division of France Telecom, says, "Increasing the bit rate per wavelength channel leads to potentially better equipment integration, higher capacity, and lower network costs. So as to enable new high-bit-rate services combining voice, data, and video, France Telecom needs to increase its network capacity at the lowest costs. This is why we analyze new disruptive technologies including 160 Gbits/sec."
One key issue of the trial was the compatibility of installed fiber infrastructure with such high channel bit rates over long distances. "The Marseille field trial demonstrated the great potential of France Telecom fiber infrastructure, thus allowing smooth network growth for many years," Viginier adds.