面向带宽碎片最小化和QoS保障的数据中心网络流量调度算法

随着数据中心网络流量的迅速增长，如何提高数据中心网络性能和服务质量成为了研究热点。然而现有的流量调度算法在网络负载加大时，一方面会导致网络带宽碎片化从而使得网络吞吐量降低，另一方面忽视了流量应用需求导致网络服务质量较差。为此，该文提出一种面向带宽碎片最小化和QoS保障的动态流量调度算法，算法综合考虑了带宽敏感的大流、时延与丢包敏感的小流的不同需求，首先根据待调度流的源地址和目的地址建立最短路径集，其次从中筛选出满足待调度流的带宽需求的所有路径，然后根据路径剩余带宽信息和小流应用需求情况为每条路径建立权重函数，最后根据权重函数值利用轮盘赌算法选择转发路径。实验仿真结果显示，与其它算法相比，所提算法降低了小流的丢包率和时延，同时在网络负载较大时提升了网络吞吐量。

A Traffic Scheduling Algorithm for Bandwidth Fragmentation Minimization and QoS Guarantee in Data Center Network

With the rapid growth of Data Center Network (DCN) traffic, how to improve the performance and service quality of data center network become a research hotspot. However, when the network load increases, the existing traffic scheduling algorithm on the one hand may cause bandwidth fragmentation results in the network throughput decrease, on the other hand, it neglects the traffic application requirements to lead to poor QoS. Therefore, a dynamic traffic scheduling algorithm for bandwidth fragmentation minimization and QoS guarantee is proposed. The algorithm takes into account the different requirements of the bandwidth-sensitive large flows, and delay sensitive and packet-loss sensitive small flows. Firstly, the shortest path set is established according to the source address and destination address of the to-be-scheduled flow. Secondly, all the paths that satisfy the bandwidth requirement of the to-be-scheduled flow are selected. Then, the weight function is established for each path according to the free bandwidth of the path and the application requirements of the small flow. Finally, the forwarding path is selected based on the weight function value by roulette algorithm. The network simulation results show that when the network load increases, the proposed algorithm reduces the packet loss rate and delay of small flows, and improves the network throughput compared with other algorithms.