last mile
n. The portion of the telephone or cable system that is wired directly to consumers' homes.
The goal is to upgrade the TCI and Time Warner systems so that they can be used to carry telephone calls. AT&T operates the nation's largest long-distance network, but has no way to carry calls "the last mile," from an AT&T phone office to the caller's home. For that, AT&T has had to depend on leasing local lines from the Baby Bell phone companies.
—Hiawatha Bray, “Healing a sickly giant,” The Boston Globe, February 02, 1999
For decades, The Last Mile has been a sedate place in which to do business, a pokey stroll in the park in terms of corporate competition. The telephone and cable giants have faced few, if any, threats to their dominant market shares.

But that's about to change, thanks to impending widespread introduction of high-speed Internet access, known generally within the telecom industry as "broadband technology."

Within the next six months, the race to offer broadband will become the most hotly contested business battle of 1999. The Last Mile, in other words, is about to become the telecom equivalent of the Daytona 500.
—Joe Kilsheimer, “High-Speed Internet Access Sparks Race Along the Last Mile,” The Orlando Sentinel, January 04, 1999
1981 (earliest)
Shaping up is a battle between the cable and telephone industries for the right to supply in the next century "the last mile" of connections between inter-city networks (or satellites) and the customer's home. The last mile is the most lucrative part of the business.
—“The wiring of America,” The Economist, June 20, 1981