===== Overview

OpenFlow is a vendor-neutral standard communications interface defined
to enable interaction between the control and forwarding layers of an
SDN architecture. The OpenFlow plugin project intends to develop a
plugin to support implementations of the OpenFlow specification as it
develops and evolves. Specifically the project has developed a plugin
aiming to support OpenFlow 1.0 and 1.3.x. It can be extended to add
support for subsequent OpenFlow specifications. The plugin is based on
the Model Driven Service Abstraction Layer (MD-SAL) architecture
(https://wiki.opendaylight.org/view/OpenDaylight_Controller:MD-SAL).
This new OpenFlow 1.0/1.3 MD-SAL based plugin is distinct from the old
OpenFlow 1.0 plugin which was based on the API driven SAL (AD-SAL)
architecture.


===== Scope

* Southbound plugin and integration of OpenFlow 1.0/1.3.x library
project
* Ongoing support and integration of the OpenFlow specification
* The plugin should be implemented in an easily extensibile manner
* Protocol verification activities will be performed on supported
OpenFlow specifications

===== Architecture and Design

====== Functionality

OpenFlow 1.3 Plugin will support the following functionality

* Connection Handling
* Session Management
* State Management.
* Error Handling.
* Mapping function(Infrastructure to OF structures).
* Connection establishment will be handled by OpenFlow library using
opensource netty.io library.
* Message handling(Ex: Packet in).
* Event handling and propagation to upper layers.
* Plugin will support both MD-SAL and Hard SAL.
* Will be backward compatible with OF 1.0.

*Activities in OF plugin module*

* New OF plugin bundle will support both OF 1.0 and OF 1.3.
* Integration with OpenFlow library.
* Integration with corresponding MD-SAL infrastructure.
* Hard SAL will be supported as adapter on top of MD-SAL plugin.
* OF 1.3 and OF 1.0 plugin will be integrated as single bundle.


====== Design

*Overall Architecture*

.overal architecture
image::openflowplugin/plugin_design.jpg[Overal architecture,389, 289]