Impairment-aware optical network virtualization in single-line-rate and mixed-line-rate WDM networks

Optical network virtualization enables network operators to compose and operate multiple independent and application-specific virtual optical networks (VONs) sharing a common physical infrastructure. To achieve this capability, the virtualization mechanism must guarantee isolation between coexisting VONs. In order to satisfy this fundamental requirement, the VON composition mechanism must take into account the impact of physical layer impairments (PLIs). In this paper we propose a new infrastructure as a service architecture utilizing optical network virtualization. We introduce novel PLI-aware VON composition algorithms suitable for single-line-rate (SLR) and mixed-line-rate (MLR) network scenarios. In order to assess the impact of PLIs and guarantee the isolation of multiple coexisting VONs, PLI assessment models for intra- and inter-VON impairments are proposed and adopted in the VON composition process for both SLR and MLR networks. In the SLR networks, the PLI-aware VON composition mechanisms with both heuristic and optimal (MILP) mapping methods are proposed. A replanning strategy is proposed for the MILP mapping method in order to increase its efficiency. In the MLR networks, a new virtual link mapping method suitable for the MLR network scenario and two line rate distribution methods are proposed. With the proposed PLI-aware VON composition methods, multiple coexisting and cost-effective VONs with guaranteed transmission quality can be dynamically composed. We evaluate and compare the performance of the proposed VON composition methods through extensive simulation studies with various network scenarios.