IT has already virtualized servers and storage, what about networks?
Today’s networks are having to evolve because they were never designed to support the unprecedented traffic demands of businesses, users and applications. Telecom operators today cannot fully predict how their customers will use services and what demands this will put on the network. These demands change dynamically by the hour, by the minute, by the second. And it is simply not economical for operators to build a highly over-capacity network, which sits idle most of the time and handles complexity and volume for just some of the time.
Enter Software Defined Networking (SDN) and Network Function Virtualization (NFV). The idea behind these is to add more flexibility to networks. SDN allows networks to be configured and re-configured much more dynamically by splitting the Management (Control Plane) from the Traffic (Data Plane). This allows for more flexibility on how to route traffic and how to handle varying traffic loads. NFV migrates the functions of dedicated switches and routers to servers, which run ‘Virtual’ instances of switches, services and applications, which again provides more flexibility to the operators.
That’s the upside. Now the downside: complexity and much reduced control of physical parameters of the network. Operators can design and build router networks based on the known hardware characteristics of the devices. Once they build the network, they have an idea of what the performance (latency, bandwidth, etc.) should be. When the management of the traffic is detached from the traffic itself and more so when the physical hardware is not a known platform but a generic server blade, the performance of the network suddenly goes from mostly-known to mostly-unknown.