Multicast Data Transmission Restore In Fat-tree Data Center Networks

Most of the current data centers adopt a multi-tree called Fat-tree model,which uses abundant multiple paths to achieve bisection bandwidth and deploys a number of core switches to scale in its roots.Fat-tree data center networks can provide multiple links between any two hosts,further providing large aggregate bandwidth.However,the uneven distribution of traffic in the Fat-tree often leads to low efficiency of the transmission,so that the network bandwidth of the system cannot be fully utilized.Moreover,it may cause reduction of network processing capacity and result in the unpredictability of system performance.If there is no effective scheduling strategy and data recovery strategy,it is easy to cause link congestion and node receiving data failure,which will prevent the system to achieve high performance of parallel links and raise a lot of unpredictable problems.In order to solve the above problems,in this paper,we will propose a Multicast Data Restoration Strategy(MRDC)scheme in fat-tree data center networks.In this scheme,each receiver will be assigned to a suitable data backup system,which can recover the data by this system automatically according to the position of the server.Which finishing multicast transmission,the system can detect the failure server which has lost packets.If it does,the nearest server will transmit the same data to failure server until reception is successful.In addition,during the transmission of data,MRDC will firstly inform the multicast manager of all the information of the receiving servers,and then multicast manager will recover data by choosing the optimal link so as to avoid the possibility of link congestion during data restoration.Furthermore,the multicast routing algorithm can reduce packet loss rate and increase throughput of servers while does not increasing the link load and CPU usage rate significantly.There are many links between two devices in data center networks.In other words,there are many paths that can be chosen to send packets from one devices to another device.If not properly choosing a transmission path,it is easy to cause the oversubscription of a link during large-scale data transmission.In this case,it will cause the failure of data transmission,affect the performance of the system and lead to many unpredictable phenomena.Thus,we design a multicast routing algorithm to select the optimal link according to historical state and current traffic load of the link so as to promote the overall performance of the system.Therefore,it greatly reduces the bandwidth consumption and transmission delay,and increases the application throughput.