Given that virtualization really is a paradigm shift for network architectures—how networks are developed and operated and the services we use are created, assured and billed—it is useful to remember that Software Defined Networking (SDN) has been around for a while. For example, did you know that WMFoundry was first introduced in 2000? Its close cousin for virtualization of CSP (News 
– Alert) infrastructure, Network Function Virtualization (NFV), has very deep roots going back to the soft switches of the early part of the 2000s as well.
