Efficient and accurate analytical performance models for translucent optical networks

This paper presents new analytical models for computing the blocking performance of translucent optical networks with sparsely located optical-electrical-optical regeneration nodes. Due to physical layer impairments such as noise and crosstalk, there is a maximum distance [called the transmission reach (TR)] that optical signals can travel before they have to be regenerated. Regeneration nodes that are allocated to a lightpath can also be used for wavelength conversion besides mitigating PLIs. The quality of transmission of a lightpath is satisfied if the length of each segment between two allocated regeneration nodes is less than the TR. We develop analytical models to estimate the call blocking probability for two typical regeneration node allocation policies. The first policy allocates regeneration nodes when the lightpath needs either regeneration or wavelength conversion, while the other allocation policy allocates regenerators only for signal regeneration. The analytical models strike a balance between computational complexity and prediction accuracy. The models are validated using extensive simulation results for a variety of network topologies and parameters.