With WAN to WAN enabled on the MCN, remote site routes are advertised by MCN.
· Clients are aware of MCN local routes as well as other client site routes
· From client perspective, all routes are considered as MCN routes
When WAN-to-WAN forwarding is not enabled on the MCN, Branch to Branch communication issues are encountered in the customer network.
SD-WAN appliances running in client mode are not aware of other branches subnets until WAN-to-WAN forwarding is enabled on MCN. Once this option is enabled, branch SD-WAN nodes become aware of other branch subnets and all the traffic destined to other branches is forwarded to MCN. MCN routes it to the correct destination.