http://www.technolog...ald1204.asp?p=1
The company astonished Wall Street and telecom insiders in January when it announced that it would spend $2 billion over the next two years to move to Internet-type switchinga far more ambitious overhaul than those planned by its sibling phone companies, such as SBC and BellSouth.
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It would be easy to mistake the Baldwin Park central office for a museum of the history of telephony: the building has hosted three generations of phone network technology since its construction early in the last century. The first and longest-lived technology was the step switch.For decades, step switches occupied thousands of central offices, whirring, clicking, and banging as they opened circuits and shunted calls to their destinations.
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In Baldwin Park, the mechanical step switches were finally ripped out in the 1970s and replaced with digital switches. All thats left of the old apparatus are two walls of steel coils big enough to hold wine bottles. Now 11 rows of digital circuit-switching equipment house thousands of playing-card-sized circuit boards. Copper wires running from homes and businesses across Baldwin Park and parts of adjacent communities terminate here
