A Brief Introduction To OpenFlow, November 14, 2011 OpenFlow is a specification now managed by the Open Networking Foundation, which defines the functions and protocols used to centrally manage switches via a centralized controller.
Do you need OpenFlow to manage your network? No. Can OpenFlow controllers provide features and functions better than what are available today via existing standards? Absolutely. An OpenFlow controller can, within its OpenFlow management network, potentially replace most of the management protocols running in your existing network. You don't need to worry about loops, VLANs can lose meaning if needed, and you can use all of your capacity between any OpenFlow-enabled switches. You can potentially design the network of your dreams completely in software and deploy with a push of a button. If we sound breathless, it's because the potential to unlock the power of your network is very real. The breadth of that power depends on the capabilities of the controller.
Ivan Pepelnjak of IOShints reminds us that you don't need OpenFlow to solve every age-old problem. While his examples are directed at LLDP, his point applies to many Ethernet-related functions.