A method for establishing an in-band connection in an OpenFlow network and switch where the method includes receiving, from a first port, a SYN packet passing through a first path, recording the first port as a first transmit port between a target controller and a source switch, according to the SYN packet passing through the first path, in an in-band connection list, and forwarding the SYN packet passing through the first path, receiving a SYN response packet from a second port, determining the first transmit port between the target controller and the source switch, and forwarding the SYN response packet from the first transmit port between the target controller and the source switch which enable controllers and switches provided by more manufacturers are compatible.