Modeling an OBS Node under Critical Load and High Utilization Conditions

We consider a bufferless optical burst switching optical cross connect modeled as a continuous-time Markov chain based on a generalized Engset model. We focus specifically on critical load and other given levels of high utilization conditions and evaluate the required number of wavelength channels per cable to keep the blocking probability below a given level. We observe that although a large number of wavelength channels per cable are required to achieve low blocking probability under critical load condition, the required number of such channels decreases significantly if the utilization is allowed to drop to 90% or 80%. We also propose a new blocking probability approximation that is more accurate than previous approximations under critical load condition.