A transmitter used in a transmission system in which a first network is connected, via a second network, to a third network, the transmitter being arranged between the first network and the second network, the transmitter includes: a generator configured to specify an identifier of data area in which communication data affected by a failure occurred in the first network are stored, in a frame transmitted from the second network, and to generate failure information associated with the identifier specified; and a transmitter configured to transmit the failure information generated by the generator, via the second network, to another transmitter arranged between the second network and the third network.