upgrading U.S. telephone network technology
Major upgrades of the U.S. telephone network have taken decades. The first U.S. commercial installation of a automatic (mechanical) telephone switch occurred in 1892.[1] In the Bell System in 1920, nearly three decades later, only 2% of telephones were automatically switched.[2] The share of telephones in the U.S. that were automatically switched didn’t rise to … Continue reading upgrading U.S. telephone network technology