Robust plans for spectrum allocation in elastic flexgrid optical networks

We study the spectrum allocation problem in flexgrid optical networks under demand uncertainty. Using elastic spectrum allocation the slots assigned to a lightpath can be changed under different restrictions without service disruption. We study five different technologies to manage these changes. It is shown that the two least efficient models are less computational demanding than the other variants. A computational study using comparable integer linear programming formulations reveals that the additional slots required by these models is directly dependent on the restrictions of the employed technology.