OVN seems to assume that external networks are realized by a physical network, which is bridged to the logical router through a localnet port. In particular, OVN depends on ARP (and GARP) in the physical network to learn MAC bindings. However, it doesn't have to be this way. In this talk, we explore the possibility of realizing an external network as a logical switch on the overlay. This can be accomplished by using existing primitives in OVN, with a few minor modifications. We are interested in contributing our patches upstream, and working with the community to identify long-term improvements for this model.
