OpenFlow is the first standard communications technology between the control and forwarding layers of an SDN architecture. OpenFlow allows direct access to network devices and manipulation of the forwarding plane of network devices such as switches and routers. It separates the programming of routers and switches from underlying hardware
OpenFlow-based SDN technologies enable IT to address the high-bandwidth, dynamic nature of today’s applications, adapt the network to ever-changing business needs, and significantly reduce operations and management complexity.
The technology consists of three parts –
- Flow tables installed on switches
- controller and
- Proprietary OpenFlow protocol for the controller to talk securely with switches.
Flow tables are set up on switches. Controllers talk to the switches via the OpenFlow protocol and enforce policies on flows. The controller could set up paths through the network customized for specific requirements such as application requirements, low delay, minimal hops or high speed.
Several established companies including IBM, Google, and HP have either fully utilized, or announced their intention to support, the OpenFlow standard.
Origin of Openflow –
In year 2006, Martin Casado, a PhD student at Stanford University in Silicon Valley, California, developed something called Ethane.- Technology for central management global policy using “flow-based network and controller” along with SDN.
Further research led to what became known as OpenFlow, which was conducted jointly by teams at Stanford and the University of California, Berkeley.
Benefits of OpenFlow –
- Enable innovation/differentiation
- Accelerate new features and services introduction
- Centralized Intelligence
- Simplify provisioning
- Optimize performance
- Granular policy management
- Decoupling of Hardware & Software, Control plane & forwarding, and Physical & logical config