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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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