Uncertain Multicast Routing In Software-Defined Networking

Multiple duplications are scattered and deployed in network and any one of them can be used as the source of multicast transmission.The uncertain sources can be a good opportunity of optimizing multicast routing by sharing paths and reducing multicast links.Unfortunately,current multicast methods are stubborn to exploiting the advantages of uncertain sources.And each network device has their own control logic which limits flexibility and correctness of multicast routings.All above drawbacks make it hard to deploy uncertain multicast routing.Recently,software-defined networking makes it possible to innovate network applications,such as uncertain multicasting.It aims at decoupling control logic from data planes of devices.This innovation forms the brain of network which can be programable.In order to achieve these objectives,the following work is carried out:(1)Minimizing transfer cost of uncertain multicast routingDistributed file systems for data center provide redundant data duplications which are stored in different servers to improve data transfer.For each receiver,the sender's uncertainty problem is how to select the proper senders for the data source for minimizing total transfer cost of uncertain multicast routing.In fact,it is an NP hard problem.In our work,the optimal model of the problem is built,and approximation algorithms are designed.(2)Uncertain multicast routing algorithms designing for the minimum costMinimum-cost multicast routing can be abstracted as the famous Steiner tree problem,which can exploit the advantage of uncertain sources to optimize multicast routing.In this paper,the two approximation algorithms were designed.One is Primary-MCF(P-MCF)method,and its innovation is to build the minimum-cost forests,where each receiver is connected to one and only one sender.The other method is Enhanced-MCF(E-MCF),which can achieve further optimized approximation ratio than P-MCF.The Steiner tree is approximated by the current minimum spanning tree.Current algorithms ignore a lot of links which can be shared by multicast paths if they are added into routings.E-MCF method can find shared nodes which are located in these multicast paths.Shared nodes are used to build a better multicast routing with more shared links,which reduce the total transfer cost.Algorithms are tested under the three types of large-scale data center network,i.e.random network,random regular network and the scale-free networks.(3)An innovative design of multicast applicationIn addition to the previous two questions,a protocol for multicast transmissions is designed.This design includes adding multicast group membership,setting up and managing a multicast group,and constructing forwarding of multicast routing and configuration rules on data plane.Different from the traditional network,SDN advocate separating control logic from data plane.Hence,centralized control logic can simplify multicast group management.Meanwhile,traditional IP multicast management are also compared.To sum up,SDN will gradually replace the existing network.Hence,SDN can give a huge impact on current future network application,such as a renewed design for multicast.