4 x 40 Gbit/s transmission in 500 km long, dispersion-managed link, with in-line all-optical wavelength conversion

Transmission of 4 x 40 Gbit/s channels over a 5 x 100 km dispersion-managed link with in-line wavelength conversion of one channel is reported. Polarisation-independent conversion is demonstrated exploiting four-wave mixing in semiconductor optical amplifiers. Error-free operation after conversion and propagation is shown over both G.655 and G.652 fibres.