Which of the following connects the SDN controller and SDN networking devices and relays information...

In Software Defined Networking (SDN), APIs are used to manage the communication between different components of the network. The Southbound API connects the SDN controller to the networking devices such as switches and routers, enabling the controller to send instructions to the network devices and gather data from them. This API is essential for the controller to enforce policies and ensure the proper functioning of the network infrastructure.

The other APIs are:

Northbound API: Interfaces between the SDN controller and the applications running on the network.

Eastbound API and Westbound API: Generally used for communication between different SDN controllers or other similar systems.

References:

EC-Council Certified Network Defender (CND) Study Guide

SDN architecture documentation