Routing,Spectrum And Core Assignment In Space Division Multiplexing Flexible Optical Networks

With the emergence of new applications and development of Internet technology,the network capacity required is growing explosively.In order to solve the waste of spectrum resources caused by excessive granularity of resource allocation and inflexibility in traditional wavelength division multiplexing network,flexible optical network with finer and flexible use of spectrum resources has come into being.However,as the transmission capacity of the traditional single-mode fiber is approaching the limit,the flexible optical network with space division multiplexing technology has become a hot topic in recent research,because it can greatly improve the optical fiber transmission capacity.Compared with the allocation of routing and spectrum resources in flexible optical networks,space-division multiplexing flexible optical networks have added new dimensions to make resource allocation more complicated.How to solve the problem of routing,spectrum resources and spatial channel assignment is very important.Multi-core fiber is considered to be one of the most promising technologies in the space division multiplexing technology.The integration of multi cores in the optical fiber can greatly improve the transmission capacity of the fiber.However,with the increase of the number of cores in the optical fiber,the inter-core crosstalk problem is caused,which seriously affects the signal transmission quality in the fiber.In addition,the problem of spectral fragmentation in flexible optical networks still exists in the space division flexible optical network,which seriously affects the network spectrum utilization.In order to solve the crosstalk problem,researchers have not only done a lot of researches on the physical structure of optical fibers,but also proposed a variety of routing,spectrum and core assignment algorithms for multi-core fibers.In this paper,we study the routing,spectrum and core assignment algorithms in space division multiplexing flexible optical networks and propose a novel resource allocation algorithm based on frequency slot areas.The algorithm takes advantage of the frequency slot area,taking into account the influence of crosstalk and spectrum fragmentation between cores,allocates different spectrum sets for the traffic requests and selects suitable cores for transmission.The simulation results show that the algorithm has good performance.Compared with traditional resources assignment algorithms,the proposed algorithm can better improve the resource utilization of the network and reduce the traffic blocking rate and the inter-core crosstalk.