To enable a management device to grasp secret information at the time of installation and a change of a mediation device or a device to be managed without leakage to the outside when the mediation device or the device to be managed is newly installed in an office, etc., of a user of equipment and when the secret information of the existing mediation device or the device to be managed is changed.

When network environment information as the secret information required for performing communication with the management device 102 via the Internet 112 is inputted from an input section, the mediation device 101 sets the network environment information by writing it in a flash ROM, acquires management object information such as the secret information required for performing communication with the management device 102 via the Internet 112 from an image forming apparatus 100 via a LAN, reads the network environment information and the management object information in the flash ROM after setting the management object information by writing it in the flash ROM and transmits them to the management device 102 via a public line 103.