What Is SDN (Software Defined Networking)?

Question: What Is SDN (Software Defined Networking)?

Answer: Software Defined Networking (SDN) is an effort in the computer networking industry to develop a new approach for how large networks are designed and built. Larger network installations utilize a mix of routers and network switches plus other access points that enable clients to join. Significant technical effort is required to set up and maintain these network configurations. In particular, technicians must perform labor intensive hardware installs and firmware/software upgrades that normally require them to be physically present. The concept of Software Defined Networking allows these routers and other devices to expose new interfaces that allow them to be administered and controlled remotely, greatly simplifying the job of network administration, saving time and money but also reducing the risk of human errors.

OpenFlow is a technology standard developed to make SDN possible, defining the remote communication interfaces necessary to control routers and switches that are built to support it. With OpenFlow a network administrator can define configuration changes and then automatically push them out to the rest of the network through its communication protocol.

SDN has received much attention in the industry and press, hailed by some as a revolutionary approach to network management and derided by others as a passing fad. While some vendors have built OpenFlow compatible gear, and alternatives to OpenFlow are under active development, the future impact of Software Defined Networking remains to be seen.