What are the key features of SDN network architecture?

The key features of Software-Defined Networking (SDN) architecture include a clear separation between the control plane and the data plane (forwarding layers), centralized control, and the use of open interfaces. This separation allows for more flexible and efficient network management.

Centralized control gives a single management point for the entire network, enabling administrators to make changes and optimizations without the need for manual configuration of each individual device. This approach allows for dynamic reconfiguration and improved overall network performance.

Open interfaces facilitate communication between the different layers and components within the network, promoting interoperability and flexibility. By adhering to standard protocols, SDN can easily integrate various vendors' equipment and technology, fostering innovation and reducing vendor lock-in.

In contrast to the other options provided, the characteristics mentioned in the correct choice accurately reflect the foundational principles of SDN, particularly the importance of separation and centralization in the architecture.