An Effective Routing Mechanism for Link Congestion Avoidance in Software-Defined Networking

In the network environment with limited network resources, the overall bandwidth is usually competitively shared among various application users. The traffic engineering techniques presented for resolving the bandwidth sharing, e.g. limited traffic rate and traffic blocking, may not be able to satisfy the requirement for all types of services. In this paper, we propose an effective routing mechanism for link congestion avoidance in the software-defined networking (SDN) environment. We use a SDN controller to handle actions and forwarding rules. The bandwidth is dynamically allocated to deal with link congestion using a centralized control mechanism. According to the bandwidth utilization, we redirect the traffic from congested links to enhance the efficiency of link usage. In the experiments of emulating congested traffic, we are capable of getting better network performance of throughput, jitter, and packet loss rate using the proposed traffic rerouting, as opposed to the environment without traffic rerouting.