OpenFlow specification: Software Defined Network

OpenFlow specification outbreak

In recent weeks, with the activation of the Open Networking Foundation (ONF) and the announcement of support for almost all mainstream network providers, the OpenFlow specification broke out in the network field. In fact, the OpenFlow switch has been published on Interop Las Vegas 2011 and has aroused great controversy.

SDN allows network engineers to control and manage their networks so that they can better serve their respective needs, thereby increasing network functions and reducing operating network costs. Open Networking Foundation supports OpenFlow specifications, which will ultimately implement the network that defines software.

What are OpenFlow specifications?

OpenFlow is a software API that allows a "controller" to send configuration information to a vswitch. This configuration usually refers to a "stream" and some "operations" attached to it ".

A stream is a set of defined frames or data packets (similar to an MPLS stream) and a group of operations. For example:

Source IP/Port, Destination IP/Port, and Drop.

Source IP, Destination IP, and QoS Action.

Source MAC, Destination MAC, and L2 Path.

With OpenFlow, you can send a set of rules to the vswitch or vro of a "configuration" device. Each device then uses the data according to its type. The vswitch updates its MAC address table to forward frames. The vro adds an access list and the firewall updates its rules.

What is a software defined network?

When organizations migrate network configurations from devices to software platforms, vswitches become simpler and cheaper. However, the main benefit is that the network configuration can be managed by the central controller.

A Software Defined network is a software that contains algorithms, mathematics, analysis, and rules. It comes from a rule group and uses OpenFlow to download the configuration to a network device. Therefore, when the Controller evaluates and rebalance the configuration, the network may be reconfigured dynamically.