Nortel Networks Circuit Card - Manual (Page 177)

NT1R20 Off-Premise Station Analog Line card Page 177 of 906
Circuit Card Description and Installation
local office, or through a distant office. The line is not switched at these
offices; however, depending on the facilities used, the local office serving the
OPS station can provide line functions such as battery and ringing. Facilities
are generally provided by the local exchange carrier (usually, OPS pairs are
in the same cable as the PBX-CO trunks). The traditional OPS scenario
configuration is shown in Figure 25 on
page 178 .
Note: Do not confuse OPS service with Off-Premise Extension (OPX)
service. OPX service is the provision of an extension to a main subscriber
loop bridged onto the loop at the serving CO or PBX. Do not confuse
CLS OPS (assigned in the Analog (500/2500-type) Telephone
Administration program LD 10) with OPX, which denotes Off-Premise
Extension service.