Virtual networks make things easier for the user at the planning level… at least in theory.
Network services don’t spring up unbidden from the earth but rather they’re coerced out of infrastructure in response to business and consumer opportunities. Every operations and management paradigm ever proposed for networking includes an explicit planning dimension to get the service-to-infrastructure and service-to-user relationships right. On the surface, virtualization would seem to help planning by reducing inertia, but don’t you then have to plan for virtualization? How the planning difficulties and improvements balance out has a lot to do with how rapidly we can expect virtualization to evolve.
What virtual networks do is disconnect “service” from “network” in at least some sense. They can do this by laying a new protocol layer on top of existing layers (the Nicira/VMware or software-defined WAN model), or by disconnecting traffic forwarding and network connectivity from legacy adaptive protocols (OpenFlow SDN and white-box switches).
Read more at No Jitter
