Abstract: In the present invention, fast dynamic dispersion compensation on a per-packet basis is performed by using a header recognition scheme at each node in an optical network to extract from each packet the path and bit-rate information. A decision can then be taken on whether dispersion compensation is needed for that packet, and if so, what would be a suitable amount of such compensation.

Abstract: In a method of transmitting data over an optical transmission network, the data to be transmitted is divided into a plurality of data streams, each of which comprises data packets of predetermined lengths with the packet lengths of each stream differing from those of the other streams. Individual packet streams are associated on to respective wavelengths of a wavelength division multiplexed optical signal for transmission over the network.

Abstract: An optical tunable filter/wavelength converter comprises an input for multiple wavelength traffic carrying signals &lgr;1-&lgr;m, an output for converted wavelength carrying signals (&lgr;1′-&lgr;m′), means (20) for routing each of the traffic carrying signals through a demultiplexer to an individual semiconductor optical amplifier (SOA) (22) or to an interferometer arrangement. A laser source (26) provides a further input wavelength to the SOAs, or to the interferometer arrangements, to enable cross-gain or cross-phase modulation from the input signal which thereby provides the converted signal. Means is provided for selectively routing the converted signal to the output.

Abstract: An optical routing device for wavelength division multiplexed (WDM) optical signals includes an optical switch matrix (50) having a first optical switch array (54) and a second optical switch array (52), the first optical switch array being adapted to couple optical signals to the second optical switch array on the basis of the wavelength of respective optical signals. The second optical switch array (52) includes a number of optical switch devices, each of which is dedicated to route traffic on a respective wavelength. The device includes a drop traffic path and a through traffic path, in which the drop traffic path includes a transponder unit (170; 220) that is selectively reconfigurable to couple signals to a through traffic path and thereby provide a signal regeneration path. The transponder unit (170; 220) may be tunable so as to provide a wavelength translation function for any optical signal received by the transponder unit. This feature enables efficient sharing of transponders.