FACSIMILE COMMUNICATION PROTECTING DEVICE

PURPOSE:To prevent erroneous transmission and erroneous reception in the same group occurring by installing a facsimile communication protecting device reliable to even facsimile equipment of different manufacturer at a telephone exchange and facsimile equipment, respectively. CONSTITUTION:After outgoing is issued from the facsimile equipment 1 and the facsimile equipment 2 responds to that by receiving incoming, the facsimile communication protecting devices 4 and 5 hold a line transiently, and the communication of a password is performed between the devices 4 and 5, then, collation is performed. Therefore, the equipment 1 and 2 are not related to the collation at all, which enables a facsimile communication limiting network only in the same group to be comprised even when manufactures are different. For example, assuming the password of the device 4 as (4a21), the outgoing from the facsimile equipment 3 without providing with the facsimile protecting device to the equipment 1 is refused. Because, since no dial signal A is provided at the button of a telephone set 7 connected to the equipment 3, no password (4A21) can be issued. Therefore, it is possible to prevent erroneous incoming from a group other than the same group from being received.