340 Gbit/s (32 × 10.66 Gbit/s) WDM transmission over 6054 km using hybrid fibre spans of large core fibre and dispersion shifted fibre with low dispersion slope

340 Gbit/s (32/spl times/10.66 Gbit/s) WDM transmission over 6054 km with a bit error ratio of less than 10/sup -9/ has been successfully demonstrated, using low dispersion slope hybrid fibre spans of large core fibre and dispersion shifted fibre and optical signal power optimisation.