SD-WAN Underlay

[RS19]

I have a question regarding the underlay networking of Cisco SD-WAN.

Ex - I am using MPLS or Internet link as my underlay. OSPF is my service side routing protocol used for my DC & branch routing.

To establish IPSec tunnel over the underlay either with MPLS link or Internet link is it required to use BGP in case of Cisco SD-WAN ?

Is BGP required to have the underlay communicate with each other for establishing the IPSec communication ?

[stefan.radovanovici]

Your vedge must simply have IP connectivity over MPLS to the controllers and to the other vedges. How that's achieved depends solely on what your MPLS provider requires you to use between their CPE and your vedge. I can be static routing, BGP, OSPF.