Crosstalk-Aware Optimal Resource Allocation Approaches In Elastic Optical Networks With Multi-Core Fibers

It has brought a huge increase of network data with the development of network applications,which causes insufficient network bandwidth resources.The traditional wavelength division multiplexing(WDM)optical network has been unable to meet the requirements of network transmission capacity.While the multi-core fiber elastic optical networks(MCF-EONs)can greatly increase the transmission capacity due to their large capacity and fine bandwidth granularity.However,as the spatial dimension of MCF-EONs increases,the process of network resources allocation becomes more complicated.And it faces a great challenge of inter-core crosstalk.Therefore,this paper studies the resource optimization methods with the crosstalk awareness to solve the problems of both the inter-core crosstalk and the optimal allocation of network resources in MCF-EONs.Firstly,in order to effectively deal with the problem of the inter-core crosstalk in MCF-EONs,we propose the method of calculating inter-core crosstalk for the trench-assisted optical fiber with seven core.According to the inter-core crosstalk evaluation method,a quantitative evaluation method of inter-core crosstalk is valued by combining with the weak and strict inter-core crosstalk mechanisms in MCF-EONs.This provides a theoretical basis for solving the inter-core crosstalk problem in MCF-EONs.Then,considering the static traffic demands in MCF-EONs,we establish integer linear programming(ILP)models to minimize inter-core crosstalk according to the weak and strict inter-core crosstalk mechanisms.And the RCSA heuristic algorithms are proposed to realize the minimum inter-core crosstalk for all traffic demands.Simulation results show that the proposed RCSA algorithms that minimize inter-core crosstalk are close to ILP models and are superior to traditional algorithms,achieving the optimization of network resources in MCF-EONs.Finally,considering the dynamic traffic demands in MCF-EONs,on one hand,we develop a service classification method to reduce the spectrum fragmentation.Moreover,we propose the crosstalk-aware RCSA algorithms based on different inter-core crosstalk mechanisms which can efficiently achieve the tradeoff between blocking probability and inter-core crosstalk.On the other hand,considering the effect of different modulation formats on the network performance,the RCSA algorithm based on different modulation formats is proposed to improve the spectrum efficiency.Simulation results show the proposed RCSA algorithm can effectively reduce the blocking probability.Also,the blocking probability and inter-core crosstalk under QPSK are better than BPSK.