Lightpath blocking performance analytical model for a single ROADM node with intra-node add/drop contention

In colorless and directionless ROADMs based on broadcast-and-select architectures, due to the intra-node contention, the number of lightpaths that can be added/dropped with the same wavelength is limited by the add/drop contention factor. In this paper, we develop an analytical model to evaluate the lightpath blocking performance for a single ROADM node with intra-node add/drop contention. The study indicates that the model is accurate to effectively predict the simulation results. Also, the add/drop contention factor shows an important impact on the lightpath blocking performance and properly raising contention factor can significantly improve the lightpath blocking performance.