Exploiting the transmission layer in logical topology design of flexible-grid optical networks

Flexible-grid optical networks are the most convincing candidate for the evolution of backbone optical networks thanks to their high spectral efficiency and flexibility. We propose an original approach to the logical topology design (LTD) problem in the offline planning phase. We deal with the LTD problem using heuristic algorithms incorporating a detailed transmission layer model. Several heuristic algorithms, allocating traffic demands in different orderings, are considered for lightpath provisioning. Traffic ordering schemes are mainly based on two parameters: traffic demands capacity and lightpath physical route length. Through simulative analyses, we provide a performance comparison of different heuristics, using parameters like spectral efficiency, amount of blocked traffic and total number of transceivers. We also show the importance of integrating a detailed physical layer modeling in the network design phase.