Patent ID: 7778184

Claim:
A remote diagnosis system comprising: a control device; a relay device which is continuously connected to said control device; and an inspection target device which is connected to said relay device by a communication network established by a connection demand from the inspection target device, wherein said control device includes a unit for transmitting a UDP (User Datagram Protocol) packet to said inspection target device, said relay device includes a unit for transmitting a control signal to said inspection target device when said UDP packet transmitted from said control device is received, said inspection target device includes a unit for establishing said communication network by making the connection demand to said relay device and transmitting a TCP (Transmission Control Protocol) connection demand to said control device, when said control signal is received, and by the TCP connection demand from said inspection target device, a TCP connection is established between said control device and said inspection target device, and thereafter said control device transmits an inspection instruction file to said inspection target device by using this TCP connection.