Full form: Software-Defined Networking
Also known as: Software-Defined Networking, software defined networking
Quick Definition
An architecture that separates the network control plane from the data plane, enabling centralised programmability.
SDN decouples the network's control plane (decision-making) from the data plane (packet forwarding). In traditional networking, each device runs its own control plane independently. In SDN, a centralised controller makes forwarding decisions and programmes the data plane of individual devices via southbound APIs (e.g., OpenFlow, NETCONF). Northbound APIs expose the controller's capabilities to applications and automation tools.
In SDN, the control plane runs on the centralised controller, not on individual network devices. The data plane (forwarding hardware) remains distributed on each device. Cisco DNA Center is an example of an SDN controller.
An API architectural style that uses HTTP methods (GET, POST, PUT, DELETE) to interact with network resources.
APIs on an SDN controller that allow applications and management tools to communicate with the controller.
APIs on an SDN controller that communicate with and programme the network devices below.
Cisco's SDN controller and network management platform providing centralised automation and analytics.
SDN decouples the network's control plane (decision-making) from the data plane (packet forwarding). In traditional networking, each device runs its own control plane independently. In SDN, a centralised controller makes forwarding decisions and programmes the data plane of individual devices via southbound APIs (e.g., OpenFlow, NETCONF). Northbound APIs expose the controller's capabilities to applications and automation tools.
In SDN, the control plane runs on the centralised controller, not on individual network devices. The data plane (forwarding hardware) remains distributed on each device. Cisco DNA Center is an example of an SDN controller.
SDN falls under the Automation domain of the 200-301 exam. Understanding it in context with related terms like northbound-api and southbound-api is essential for answering scenario-based questions correctly.