An efficient algorithm for converter placement in dynamic WDM networks

Wavelength conversion is effective in reducing the connection blocking probability and increasing the link utilization in wavelength-routed WDM networks. However, wavelength converters are expensive in the foreseeable future, which means only a limited number of converters can be deployed in a network. In such case, placement algorithms are used to determine the locations of a given number of converters such that the connection blocking probability is minimized. This paper developed a low-complexity analytical model to reflect the impact of the converter locations on the network blocking probability. Based on this model, an algorithm is developed for converter placement. Since an analytical approach is taken, the algorithm has the advantage of high efficiency, allocation of 500 converters in two exiting networks with 14 and 19 nodes takes no more than 1 second using a personal computer. Simulations show that the proposed approach outperforms the best existing algorithm in terms of blocking probability.