Software-defined networks (SDNs), as an emerging paradigm by separating the control plane from the data plane, increases flexibility and network utilization and reduces redundancy and operational cost. Traffic management of software-defined networks can be defined as network traffic monitoring and analyzing measures to improve network performance and quality of service metrics. Traffic management as an effective instrument for optimizing network traffic can offer the appropriate services according to network situation. Due to the inherent characteristics of SDN, special techniques are required to analyze, predict, and adapt the network traffic in order to achieve an efficient traffic management mechanism. This paper surveys traffic management techniques of SDN in four distinct categories including, routing, load balancing, congestion control, and flow control to cover the impressible issues. Moreover, the differences between SDN and traditional networks are analyzed in terms of traffic management necessities across the various groups to further determine the dimensions affecting research in this area. Furthermore, the available algorithms in each group and their role in traffic management are reviewed as well as the research challenges and future trends.

作为通过将控制平面与数据平面分离的新兴范例，软件定义网络（SDN）可以提高灵活性和网络利用率，并减少冗余和运营成本。可以将软件定义网络的流量管理定义为网络流量监视和分析措施，以提高网络性能和服务质量指标。流量管理作为一种优化网络流量的有效手段，可以根据网络情况提供适当的服务。由于SDN的固有特性，需要特殊的技术来分析，预测和调整网络流量，以实现有效的流量管理机制。本文从四个不同的类别对SDN的流量管理技术进行了调查，包括路由，负载平衡，拥塞控制，和流量控制来解决令人印象深刻的问题。此外，根据各个组之间流量管理的必要性分析了SDN与传统网络之间的差异，以进一步确定影响该领域研究的范围。此外，还回顾了每个组中可用的算法及其在交通管理中的作用，以及研究挑战和未来趋势。