Which component serves as the brain of the SDN operation?

The SDN Controllers act as the brain of Software Defined Networking (SDN) operations. They are responsible for making decisions about how data packets flow within the network, managing and orchestrating the devices and resources. The controller maintains a comprehensive view of the entire network, allowing it to direct traffic flows, manage policies, and enforce rules.

In an SDN architecture, flow tables define the rules for packet forwarding but they do not make decisions themselves. Data forwarding devices, such as switches and routers, execute the instructions provided by the SDN controller but lack the intelligence to manage the network as a whole. The Open Virtual Switch (OVS) is a specific implementation of a virtual switch that can be used in SDN environments, but it also operates under the direction of the SDN controller. The controller’s capabilities in centralizing network visibility and control are what distinguish it as the brain of the SDN operation.