NFV is the virtualisation of network services that are being carried out by proprietary, dedicated hardware. NFV will decrease the amount of proprietary hardware required to launch and operate network services.
Before getting into the detail of NFV, it is important to first make a distinction between NFV and Software Defined Networking (SDN). The two are different but complementary technologies. Both SDN and NFV rely on software that operates on commodity servers and switches but they operate at different levels of the network.
SDN allows administrators to manage network services through lower-level functionality. This adheres to three principles:
- Separation of control and forwarding functions
- Centralisation of control
- Ability to program the behaviour of the network using well-defined interfaces
In contrast NFV is focused on network appliances that perform path control, protocol manipulation, logging/monitor/capture, content analysis, security control and similar functions. These functions are in use today as routers, firewalls, IDS/IPS, proxy caching, WAN acceleration, data centre and WAN load balancers. The concept should allow one item of hardware to deliver all of the network related functions at a location – whilst still selecting the products you require, for example, have a network from one supplier but a firewall from another, functioning on the same hardware.