LLDP frame matching

LLDP is used to perform topology discovery in an OpenFlow network. LLDP must be enabled globally on a device and disabled on ports that belong to an OpenFlow instance. A switch sends a LLDP frame to the controller through the Packet-in message when the following conditions exist:

• The port that receives the LLDP frame from the controller belongs to an OpenFlow instance.

• The flow tables in the OpenFlow instance have a flow entry that matches the LLDP frame (the output port is the Controller reserved port).