COSMOS was a record-keeping system for Main Distribution Frame

Main distribution frame

In telephony, a main distribution frame is a signal distribution frame for connecting equipment to cables and subscriber carrier equipment . The MDF is a termination point within the local telephone exchange where exchange equipment and terminations of local loops are connected by jumper wires...

s (MDFs) in the Bell System

Bell System

The Bell System was the American Bell Telephone Company and then, subsequently, AT&T led system which provided telephone services to much of the United States and Canada from 1877 to 1984, at various times as a monopoly. In 1984, the company was broken up into separate companies, by a U.S...

. COSMOS was introduced in the 1970s after MDFs were found to be congested in large urban telephone exchange

Telephone exchange

In the field of telecommunications, a telephone exchange or telephone switch is a system of electronic components that connects telephone calls...

s. It assigns terminals so jumpers need not be so long, thus leaving more space on the shelves. COSMOS also converts customer service orders into printed work orders for staff who connect the jumpers. COSMOS orders are usually coordinated with RCMAC to ensure that translations match wiring. With good computer records, jumpers are often left in place for reuse when one customer replaces another, resulting in a great reduction in labor.