CCNA: Cisco Certified Network Associate — Question 343

What does an SDN controller use as a communication protocol to relay forwarding changes to a southbound API?

Answer options

• A. Java
• B. REST
• C. OpenFlow
• D. XML

Correct answer: C

Explanation

The correct answer is C, OpenFlow, as it is specifically designed as a protocol for communication between SDN controllers and network devices. Java, REST, and XML are not primarily used for this purpose; while REST can be involved in APIs, it does not directly handle the forwarding changes in the context of SDN communications.