Traffic engineering of software-defined networks (SDNs) refers to network traffic monitoring and network status analysis to improve network performance, which can be achieved by addressing a variety of issues such as routing, congestion control, flow control, and load balancing. In this paper, a new traffic engineering approach is proposed that attempts to manage the traffic of SDN by adjusting the retransmission timeout. In the proposed approach, the initial retransmission timeout is determined based on transmission and propagation delays, and then this time is adaptively adjusted according to the priority of the packets, which depends on the type of packet and the number of elapsed hops. The conducted simulations in the Mininet tool have validated the effectiveness of the proposed approach in comparison to counterpart methods in terms of average throughput, average bandwidth utilization, end-to-end delay, and packet loss ratio. Eventually, analysis of the time complexity and message complexity demonstrates that the overhead of the proposed approach is negligible.

软件定义网络（SDN）的流量工程是指网络流量监控和网络状态分析，以提高网络性能，这可以通过解决路由、拥塞控制、流量控制和负载均衡等多种问题来实现。本文提出了一种新的流量工程方法，尝试通过调整重传超时来管理SDN的流量。在所提出的方法中，初始重传超时是根据传输和传播延迟确定的，然后根据数据包的优先级自适应地调整该时间，这取决于数据包的类型和经过的跳数。在 Mininet 工具中进行的仿真验证了该方法与同类方法在平均吞吐量、平均带宽利用率、端到端延迟和丢包率方面的有效性。最终，时间复杂度和消息复杂度的分析表明所提出的方法的开销可以忽略不计。