In Software Defined Networks (SDN), the controller needs to collect a lot of information from the switches that it manages and issue commands to them. Therefore, it is essential to keep the control channel open and available between the controller and the switches.

In the original implementation of SDN, the control channel and data channels share the same link, which leads to the potential of jamming attacks upon the controller.

Please describe:

(1) How is the jamming attack conducted?

(2) How can an attacker identify those links shared between data channels and control channel? (You can draw a figure to help you answer the first 2 sub-questions)

(3) How can we defend against such attacks?