Modelling of routing in multi-fibre WDM grid networks

Optical WDM networking has been researched as a technique for enabling the provision of new broadband services at a reasonable cost. A major problem is determining the number of wavelengths and fibres required to support a given traffic level, for an arbitrary topology. As a preliminary to overcoming this difficulty, regular networks are studied. Two cases are considered; first, the number of wavelengths on a fibre is limited and there may be multiple fibres between adjacent nodes, and secondly, there is a single fibre between each pair of nodes that is connected, which may carry an unlimited number of wavelengths. The latter is often not practical, since the number of wavelengths is limited by cost and performance issues concerning the transmitters, receivers and demultiplexing filters, and, for long haul systems, by nonlinear effects such as four-wave mixing. Networks without and without wavelength conversion are considered