For billing purposes, service orders were entered after-the-fact into the Computel system. Collections were entered daily into a cash posting process.

In 1966, the machine had 4k memory, three 200 bpi tape units and a printer that was capable of printing 240 lines per minute.

In 1964, mark sense toll cards were processed in Rocksprings, TX, and then driven to San Antonio, TX for rating each night.

UDP Datacenter, as UDP was originally named, operated using leased floor space and time on an IBM 1401 owned by H. B. Zachry Company.

Rocksprings Telephone Company (now known as Southwest Texas Communications) had developed computer-assisted billing processes to handle its own long distance call rating. Street Gilmer's grandson, Carson Gilmer, who ran the telephone company at the time, decided to spin off the computerized billing division into a separate company and began selling the billing service to other [...]