The Deutsche Telekom boffins at Telekom Innovation Laboratories (T-Labs), with help from Alcatel-Lucent (NYSE: ALU), have managed what they believe is the first 512Gbit/s transmission over a single 100GHz wavelength channel, with signals sent across a 734 km connection in the operator's network between Berlin and Hanover and then back again. The test, which the operator stresses took place on its production network and not a lab, equates to a "usable bit rate of 400 Gbit/s," according to a DT announcement and represents a four-fold increase in current capacity. (See DT Breaks Optical Speed Record.)

The operator says that the transmission involved the use of "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."

Huawei, meanwhile, has thrown its hat into the 400Gbit/s ring with the announcement of a 400Gbit/s system prototype that boasts up to 20 Tbit/s of capacity over a single fiber and a transmission distance of up to 1,000 km without regeneration. Light Reading will be reporting more about this development from the OFC/NFOEC show floor. (See Huawei Shows 400G DWDM Prototype .)

Over in Japan, the R&D team at NTT are excited about "an optical amplification technology that provides inexpensive wide dynamic range optical amplifiers and can handle burst signals generated in Ethernet PON systems." The result is the ability to offer 10Gbit/s services over access networks at up to 100 km. NTT will be presenting its findings at OFC/NFOEC on Thursday March 8. (See NTT Trials 10G PON at 100km.)

Get all the news from the Los Angeles event at our OFC/NFOEC Show Site.

— Ray Le Maistre, International Managing Editor, Light Reading