An optical line terminal (OLT) detects content distribution conditions in terminals, and performs control for performing switching to distribution to each terminal using an individual virtual local area network (VLAN) or distribution to a plurality of terminals by broadcasting using a broadcasting VLAN, in accordance with the detected content distribution conditions. The OLT detects that the number of viewers of a predetermined channel exceeds a predetermined threshold value or is less than the predetermined threshold value, as the content distribution conditions. Further, the OLT performs switching to distribution using a broadcasting VLAN in a case where it is detected that the number of viewers of the predetermined channel exceeds the predetermined threshold value, and performs switching to distribution using an individual VLAN in a case where it is detected that the number of viewers of the predetermined channel is less than the predetermined threshold value.