Which model describes a network architecture that separates control and data planes?

The Software-Defined Networking (SDN) Model is designed specifically to separate the control plane from the data plane in network architecture. In traditional networking, both planes are typically integrated within the same physical devices (like routers and switches), where devices manage both the packet forwarding (data plane) and the routing decisions (control plane).

In the SDN architecture, the control plane is abstracted and centralized, allowing it to be managed separately from the data plane, which remains distributed across the network devices. This separation enables more flexible and programmable network management, as the intelligence and policies can be maintained in a centralized controller, while network devices can focus solely on forwarding traffic based on the instructions received from the controller. This leads to enhanced scalability, easier network configuration, and improved operational efficiency.

While the Layered Model and OSI Model describe various facets of network communication and functionality, they do not inherently define the separation of control and data planes. The Control-Plane Model might suggest an inclination towards control plane concepts but lacks the definitive structural representation of the separation present in SDN. Hence, the Software-Defined Networking Model is the most accurate choice in this context.