No. 4 Electronic Switching System
id:
no-4-electronic-switching-system-281-3956567
title:
No. 4 Electronic Switching System
text:
The No. 4 Electronic Switching System (4ESS) is a class 4 telephone electronic switching system that was the first digital electronic toll switch introduced by Western Electric for long-distance switching. It was introduced in Chicago in January 1976, to replace the 4A crossbar switch. The last of the 145 systems in the AT&T network was installed in 1999 in Atlanta. Approximately half of the switches were manufactured in Lisle, Illinois, and the other half in Oklahoma City, Oklahoma. At the time
brand slug:
wiki
category slug:
encyclopedia
description:
Telephone switching system
original url:
https://en.wikipedia.org/wiki/No._4_Electronic_Switching_System
date created:
date modified:
2023-12-10T05:02:55Z
main entity:
{"identifier":"Q4638898","url":"https://www.wikidata.org/entity/Q4638898"}
image:
fields total:
13
integrity:
14