PacketIn
PacketIn is a message in the OpenFlow protocol used by software-defined networking (SDN). It is sent by an OpenFlow switch to the controller to report a data-plane packet that could not be matched by any existing flow entry or that is configured to be sent to the controller for decision. The PacketIn message allows the controller to learn about the network state, make a forwarding decision, and install new flow rules as needed.
A PacketIn typically includes information such as the port where the packet entered the switch (in_port), a
Handling a PacketIn involves the controller inspecting the packet, determining an appropriate action, and replying with
Security and performance considerations include the potential for controller overload from excessive PacketIn messages and the