Network Function Virtualization (NFV) is a relatively new term in the industry. There have however been virtual appliances in production for over five years serving as routers, switches, firewalls, VPN concentrators and protocol redistributors. Customer case studies for the use of NFV include partner networks, the cloud as a common meeting place, cloud bursting, virtual private cloud, and extending traditional networks into the cloud. The overlap between Software Defined Networking (SDN) and Network Function Virtualization (NFV) will also be explored. How things change at scale - what happens when you try to manage hundreds of virtual networks. A glimpse into the future, and the virtual telco.