The Network Communications Module. (NCM) provides NOTIFIER's AFP-2800 Fire. Alarm Control Panels with a means to connect to NOTI•FIRE•NET™. Three types of NCM are available: NCM-W for connecting nodes with twisted-pair wire, and NCM-F for connecting nodes with multi-mode fibre optic cable and.
Honeywell

NCM-F:Network Communications
           Module, multi-mode fibre-optic cable interface