Abstract
The robustness of optical networks with respect to the accumulation of in‐band crosstalks was statistically studied in this paper, with emphases on the effect of network topology, identified by the network scale and physical connectivity. The in‐band crosstalks, a major and irreparable signal quality degrading factor, are induced by non‐ideal optical switches and demux/mux pairs at optical cross‐connect (OXC) in optical wavelength division multiplexing (WDM) networks. For the first time, our numerical simulations revealed that in a given network scale, there exists an optimum physical connectivity: the resultant overall accumulation of in‐band crosstalks can be minimized. Then the network scale was taken into account and the optimum network topology with respect to the accumulation of in‐band crosstalks was discussed for practical networks, with the limit of crosstalk ratio of the state‐of‐the‐art optical switches and demultiplexers. It was shown that proper network design can greatly relax the requirements posed on the optical switches and demultiplexers.