Analytical and simulation availability models of ROADM architectures

The paper presents analytical and simulation availability models for evaluation of optical node availability. Analytical models are developed for six ROADM (reconfigurable optical add and drop multiplexers) architectures. Availability/cost figures are calculated, compared and discussed. For one of ROADMs simulation model is created and Monte Carlo simulation of times to failure and times to repair is carried out. A new measure k-out-of-n availability of a node is introduced. Analytical and simulation availability figures are compared. The possibility of simulation model application to other node architectures is discussed.