Loop maintenance operations system

The Loop Maintenance Operations System (LMOS) is a telephone company database that plays an essential part in the act of repairing local loops (telephone lines). When a problem is reported to the Centralized Repair Service Answering Bureau (CRSAB) by a subscriber dialing the designated number (often (1)+611) it is filed and relayed through the Cross Front End, which is a link from the CRSAB to the LMOS network. The trouble report is then sent to the Front End via data link, where a Basic Output Report is requested (usually by a lineman working with ). BOR's consist of line information including past trouble history and MLT (Mechanized Loop Testing) tests. As LMOS is responsible for trouble reports, analysis, and similar related functions, MLT (which connects to LMOS via a minicomputer in the Repair Service Bureau known as the MLT Controller) does the actual testing of customer loops. MLT hardware is located in the Repair Service Bureau. This hardware is linked to the LMOS system by way of an LMOS minicomputer, which may be in a remote location or with the LMOS central processor. Test trunks connect MLT hardware to the Wire Centers, which in turn connect with the subscriber loops.

The Databases of LMOS are connected via a high speed data link.