AT&T has today (July 29) announced that it has switched off its final No. 4 Electronic Switching System (4ESS) in Anchorage, Alaska.
This system has helped power long-distance calling for more than half a century. The 4ESS was introduced in the 1970s with the purpose of connecting people and businesses across the country.
The power switch for a 4ESS system is shown the night it was powered down in Anchorage, Alaska – AT&T
As pointed out by AT&T, the 4ESS switches were bulky, occupying as much as 5,000 square feet (465 sqm) at times.
The last of the 145 systems in the AT&T network was installed in 1999 in Atlanta. The systems were manufactured by Western Electric, a former subsidiary of AT&T Corporation.
