SDN
Software Defined Networking

SDN describes the process of abstracting and centralizing much of the control activity related to packet forwarding and handling processes which would typically take place within an individual network router or switch. Therefore, the network router/switch would only be forwarding user plane traffic, whilst receiving control information on forwarding decisions from a centralized SDN Controller. In turn, the SDN Controller can provide an abstracted, end to end view of the network to SDN Applications. These SDN Applications can then request and reserve network resources which are appropriate to that application, ensuring that overall, the packet transport network is much more service and application aware.