DSMLB: Dynamic switch-migration based load balancing for software-defined IoT network

Abstract

The deployment of multiple controllers in Software-Defined Internet of Things (SD-IoT) networks enhance the distributed control plane scalability and reliability. With the rapid advancement of IoT, millions of smart devices generate enormous amounts of IoT traffic, causing significant challenges for the network to acquire the better Quality-of-Service (QoS) to the user. The control plane load management is crucial due to the dynamic nature of IoT networks and the heterogeneity of IoT devices in terms of flow generation rate. The load distribution among SD-IoT controllers relies on their available capacity to ensure optimal load balancing performance. The dynamic switch migration method was proposed in prior findings to handle load balancing distribution among controllers. However, the migration efficiency of conventional approaches is limited due to inefficient load balancing performance of the control plane after the migration of switch, leading to additional migration overhead on the network. Taking this into account, we propose a dynamic switch migration-based load balancing approach (DSMLB) to prevent control plane overhead and distribute traffic efficiently while considering heterogeneous IoT devices. The proposed DSMLB scheme measures the real-time load ratio to the mean load ratio of each controller by describing various load metrics and selecting the target controller by optimizing the migration efficiency with residual controller resource utilization. When choosing the candidate switches from the associated overloaded controller, DSMLB considers the migration efficiency and load balancing degree simultaneously for the fastest load reduction and enhances the load balancing performance. The simulation results show that DSMLB outperforms conventional approaches for efficient load balancing performance on a distributed control plane by reducing the controller response time up to 38.6% and migration cost about 45.5% on average. Moreover, DSMLB also improves controller load balancing rate and reduces communication overhead.