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IMPORTANT!  Single Layer Serialization is supported only on OpenFlow 1.3 and greater and only with Lithium design. In other case it will fall back to Multi Layer Serialization. Also, when Single Layer Serialization is turned on, RPC statistics compatibility services are not working (they are deprecated anyway, and should not be used when we have direct statistics). So if you want to use statistics compatibility services, make sure that Single Layer Serialization is turned off.

Multi Layer Serialization

Multi Layer Serialization first converts OpenFlowPlugin models to OpenFlowJava models and then serializing them to bytes and then sends them to device, and vice-versa when messages are coming back. Because of this, it is adding unnecessary overhead during this process, but is less error-prone than Single Layer Serialization, because it depends on OpenFlowJava models what are modelled to match OpenFlow specification as close as possible.

Single Layer Serialization

Single Layer Serialization is directly serializing OpenFlowPlugin models to bytes and sends them to device. This implementation should be faster than Multi Layer Serialization, but as it is serializing OpenFlowPlugin models to bytes, without depending on OpenFlow specification models, it is more error-prone.

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OpenFlow Plugin:Implementation For Single Model Layer

The main goal is to improve performance in Openflow-plugin (OFP) in order to get better times on installing flows on devices. Main idea is to use flows in form as in Openflow-java (OFJ) and avoid using translators to spare time in heavy load.

Openflowplugin

OFP now is working as layer between generic type of flow format and standard openflow specification. This kind of design is highly modular and downstream project are able to use generic type of flows which are translated into device form. Any device can by provided with own translator and therefore able to work without any change on front-end.

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