Software-Defined Networking (SDN)

Software-Defined Networking (SDN) is an approach to computer networking that allows network administrators to manage network services through abstraction of lower-level functionality. SDN separates the network control plane from the data forwarding plane, enabling the network to be centrally controlled and programmatically configured.

In SDN, network intelligence is centralized in software-based SDN controllers, which maintain a global view of the network. Administrators can programmatically configure, manage, secure, and optimize network resources via open interfaces. This contrasts with traditional networks, where the control plane and data plane are coupled within proprietary hardware devices like routers and switches. SDN enables administrators to configure routing and switching policies from a centralized point without needing to manually reconfigure individual devices. For example, they can shape traffic from a centralized controller without touching individual switches. Overall, SDN provides more agile and flexible network management by abstracting underlying infrastructure for centralized control.