Use of spare wavelengths for traffic restoration in multi-wavelength transport network

The paper describes three network protection strategies for a single link failure using spare wavelengths in multi-wavelength all-optical transparent networks. Use of spare wavelengths is shown to be effective and can be economical when a path restoration technique is used. It is also particularly suitable for high-bandwidth optical cross-connect nodes where the number of input and output ports are generally small. Based on the simulation results, the amount of redundancy required for full protection is dependent on the protection approach employed. Two algorithms for finding and allocating spare wavelengths are introduced. The algorithms are based on the genetic and heuristic algorithms