Your company is deploying a private cloud based on OpenStack and has selected Contrail Networking as its SDN controller. Which two statements are true in this scenario? (Choose two.)
A. Underlay tunnels are established between virtualized and bare-metal servers.
B. MPLS over UDP tunnels are supported.
C. Overlay tunnels are established between virtualized and bare-metal servers.
D. MPLS over GRE tunnels are supported.
Why not B ?