Hack the Route Start free Open app Containers and cloud networking
NFV (network functions virtualization)
Routers, firewalls, NAT and load balancers run as software on ordinary servers instead of as dedicated boxes.
A virtual network function (VNF) is one such function: a virtual router, firewall or load balancer, started, moved and scaled like any virtual machine. Clouds are built this way, and so is every lab here: each gateway and firewall is a Linux machine with a rule table. Related but separate, SDN splits the deciding (a controller) from the forwarding.