Software-defined networking (SDN) is a computer networking technology that separates the control plane from the forwarding plane within a network. This separation allows the network control to be directly programmable and the underlying infrastructure to be abstracted for applications and network services. With SDN, network administrators can manage network traffic flows through a centralized controller, which uses software to determine the best path for data. This can be done without having to reconfigure individual network devices, making it easier to add new services and applications, and to troubleshoot and optimize network performance.
Some of the emerging trends in Software-Defined Networking (SDN) include the use of network virtualization, the use of network functions virtualization (NFV), and the use of software-defined WAN (SD-WAN).