OpenStack Networking networks are currently flat L2 domains - every machine can reach every other machine in one hop, the domain is a broadcast domain and OpenStack Networking's task is to ensure this holds true regardless of where VMs are placed. Limitations on L2 networks hold true - L2 networks are not great at scaling, which is why there's an 'inter' in 'internet', and joining these networks together involves various sorts of encapsulation.
We can add simple layer 3 networks to OpenStack Networking. The network is no longer flat, scales better and has significant advantages for public-facing services, and standard internet routing holds sway with no encaps; it has significant advantages when you're willing to lose L2 and the features that depend upon it.
We will discuss how we could do this with a minimum of complexity, and why it's a good idea.