A hierarchical control plane for SDN (Software-Defined Networking)

[parisa.va...@gmail.com]

Hi,

I'm working on sdn . I want to have a two layer hierarchy for controllers. But I do not find any good tutorial for connecting controllers to each other and sending message betweeen them.

 I have several local controllers which control their own domain, I also have a root controller that is connected to these local controllers and control them.

How can we design this?

I wanted to ask you for help. How can you connect controllers to eachother ? 

Regards,

parisa