What Are The Components of Software-Defined Networking?
A standard SDN setup includes:
- Data plane used to move data packets through the network based on the directions given by the control plane
- A control plane used to determine where to route traffic through the SDN, following the design implemented. The control plane can follow a hierarchical design, using distributed controllers and a centralized root controller to determine where data packets should go, or a fully distributed design where controllers take a local view and synchronize together to make routing decisions.
- Applications are used to provide information about the status of the network to the controllers through a northbound interface.
- Central controllers, which route the data packets based on the information received from the applications and then provide a larger, more holistic view of the network to the applications.
- Network devices are charged with moving the data packets to the destination based on instructions from the controller.
These components are all contained in distinct locations of the SDN architecture. By keeping the control and data planes separate, the abstraction of the network control is possible in a way not available through a traditional network, and the centralized network control becomes directly programmable.