Vigor3300 Series User’s Guide
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As for the Private Branch Exchange (PBX), it is more special because it has both FXS and
FXO devices at the same time. Outside lines of the PBX are usually connected to the phone
line, at this case, the PBX acts as FXO equipment; inside lines of the PBX are usually
connected to telephones, so the PBX acts as FXS equipment.
FXS equipment
PSTN or inside lines of PBX
FXO equipment
Telephones, FAX machines and outside lines of PBX
Based on the characteristics described above that the FXS equipment and the FXO equipment
must connect with each other, please pay special attention when you use FXS card and FXO
card.
FXS card
This card can connect to the telephone, FAX machine, outside lines of PBX and FXO port on
FXO card.
