Research On Multicast RMSA In Elastic Optical Datacenter Network

With the large-scale commercial use of 5G technology,the variety and number of emerging applications are increasing rapidly.Multicast account for a large proportion of these emerging applications,such as distributed cloud computing,cloud games,Ultra HD network TV and live webcasting.Compared with other types,multicast resource allocation,i.e.routing modulation and spectrum assignment(RMSA),is more complex and requires a large amount of total bandwidth,which causes enormous pressure on the current optical backbone network.To solve this problem,the multicast oriented distributed sub-tree scheme in the elastic optical datacenter network(EODN-DST)was proposed.In the EODN-DST scheme,datacenters are used to replace the source nodes of multicast.By allocating appropriate datacenter for the destination node,the establishment of optical path consumes less network resources and uses resources more efficiently.Therefore,this paper focuses on the targeted optimization of multicast RMSA in the EODN-DST scheme.First of all,for the special grouping and routing process in the EODN-DST scheme,a K-optimal grouping distributed steiner sub-tree(K-OG-DSST)algorithm is proposed.In the grouping part of the algorithm,the distributed subtree of one grouping scheme is expanded into a forest of distributed subtrees of multiple grouping schemes,and each grouping scheme achieves the best structure through algorithm adjustment.The simulation results show that compared with the latest algorithms in elastic optical network(EON)and elastic optical datacenter network(EODN),K-OG-DSST algorithm has the best performance and the lowest blocking probability.Secondly,the network bottleneck problem in the EODN-DST scheme is studied.After finding out the cause of the network bottleneck problem,i.e.the backbone links in the network is overused(compared with the secondary links).The link-aware cost calculation(LA-CC)formula and the link-aware distributed steiner sub-tree(LA-DSST)algorithm using this formula are proposed,and the optimal parameter value of the LA-CC formula is found through simulation tests.Simulation results show that LA-DSST algorithm has the lowest blocking probability compared with the latest algorithms in EON and EODN.In summary,this paper analyses and summarizes the related technologies such as EODN and optical multicast,and improves the shortcomings in EODN-DST scheme to improve the network performance when multicast is deployed in EODN.