Patent ID: 6198721
Filing Date: 2001-03-06
Classification: H04J

Abstract:
A method for data transmission in a 2-fiber ring network having a plurality of network nodes wherein each network node contains a terminal multiplexer and/or an add/drop multiplexer, which are connected via wavelength division multiplex units to the 2-fiber ring network, the method comprising the steps of:bidirectionally transmitting first working signals between a first terminal multiplexer and a second terminal multiplexer respectively of different network nodes via a first working connection over separate first and second light waveguides on a first portion of the network;bidirectionally transmitting first protection signals between the first and second terminal multiplexers via a first protection connection on a second portion of the network wherein a first wavelength is employed for the first protection connection which differs from other wavelengths respectively employed for other connections between other multiplexers on the first portion of the network;bidirectionally transmitting second working signals between a first add/drop multiplexer and a second add/drop multiplexer respectively of different network nodes via a second working connection over the separate first and second light waveguides; andbidirectionally transmitting second protection signals between the first and second add/drop multiplexers via a second wavelength is employed for the second protection connection between the first and second add/drop multiplexers which differs from other wavelengths respectively employed for other connections between other add/drop multiplexers on the second portion of the network.