SDN中基于负载均衡的最优路径选择算法研究

针对传统网络控制与转发的紧耦合，其路径分配算法的全局性差，实时性不足，根据软件定义网络的集中控制，提出一种基于马尔科夫链负载均衡(Markov Chain-Load Balancing ，MC-LB)算法。该算法使用马尔科夫链的转移概率计算链路重要性，并同时对业务流请求量和网络负载均衡率两个目标进行优化，获得多请求下的最优路径分配。通过大量实验对比表明该算法优于传统SPF（Shortest Path First）算法，最大可以增加网络负载均衡率30%，提升网络业务流请求接受率20%。达到了负载均衡效果，提高了网络的性能。

Optimal Path Allocation Algorithm Based onLoad Balancing for SDN

To solve the problem that path allocation algorithm has poor globality and lack of real-time in the tightly couples of traditional network control and forwarding, the paper used centralized control of Software Defined Networking (SDN) to propose the Markov Chain-Load Balancing (MC-LB) algorithm. The method calculated link importance by transition probability of Markov chain, and optimized the business flow request quantity and the load balance rate of network simultaneously to get optimal path in multi-requests. Large experiment results comparing analysis proves the algorithm is superior to the traditional SPF (Shortest Path First) algorithm which can increase the 30% network load balance rate and 20% business flow request acceptance rate in some cases. The proposed algorithm achieve the effect of load balancing and improve the performance of network.