Scheme for reliable communications via radio and wire networks using transport layer connection

A highly reliable gateway device for improving the performance of communications utilizing the transport layer connection provided via a radio network, by setting up the transport layer connection between a wire terminal and a radio terminal in a form suitable for an application, or by enabling a control of the transport layer connection according to the radio communication state between the radio terminal and a base station, without changing implementation of the transport layer of a terminal connected to a wire network, is disclosed. The gateway device determines whether or not to carry out a set up of a connection in divided forms according to an information content of a packet that contains a transport layer protocol data unit requesting a set up of the transport layer connection between the radio terminal of the radio network and the wire terminal of the wire network.