A Survey of Controller Placement Problem in SDN-IoT Network

The Internet of Things (IoT) refers to the billions of intelligent physical devices connected to the Internet for collecting and sharing data. However, implementing IoT in large-scale industrial applications presents numerous challenges, including network management and scalability. These challenges encompass: complex network management tasks that are increasingly difficult to maintain, increased network resource usage, mobility, and high energy consumption. Software-defined networking (SDN) addresses these limitations by enforcing centralized control of all devices and leveraging a global network view. SDN is a networking paradigm that separates the control plane from the data plane, allowing managers to centralize the control of the network infrastructure. For large networks, such as IoT networks, multiple controllers are needed to manage the network efficiently. The Controller Placement Problem (CPP) involves the challenge of deploying the optimal number of controllers in a network while satisfying specific performance requirements such as latency, load balancing, and computation time. This paper provides an overview of recent research efforts addressing CPP issues in the SDN-IoT domain.