Joint Optimization of Latency Monitoring and Traffic Scheduling in Software Defined Heterogeneous Networks

Since the current Internet is only able to provide best-effort services, the quality of service (QoS) for many emerging businesses cannot be well guaranteed, especially for delay-sensitive services. Meanwhile, due to the privatization of the network management, it is difficult to provide on-demand QoS services in large-scale heterogeneous networks. In addition, attacks from unauthorized access users also threaten the security of the whole network. Therefore, heterogeneous networks bring new challenges to the flexible control of different network equipment. Software-defined network (SDN) is an emerging paradigm which separates the network’s control logic from the underlying different network elements. Moreover, it promotes the centralization of network control to improve end-to-end QoS services, and introduces the program ability to mitigate threats. In this paper, we design a monitoring loop of link latency by using both LLDP and Echo probing modules. Then, a dynamic routing algorithm is proposed to select optimized transmission paths based on the information of link latency. Next, we develop a routing application assorted with the monitoring mechanism by extending the RYU controller. More specifically, we implement our solution in a semi-practical SDN testbed. Finally, the overall feasibility and efficiency of the proposed solution are experimentally verified and evaluated.