T1: A Survival Guide

Chapter 1. History of the U.S. Telephone Network

All is flux, nothing is stationary.

—Heraclitus

We live in a digital world.

By digital, I don’t mean the overused “digital economy” or anything remotely related to punditry. In the beginning, there was analog. Transmitted signals were subject to fading, interference, and noise. All that changed with digital encoding and transmission. Digital signals offer superior properties for information. Perfect regeneration is possible with sophisticated error detection and correction methods. Signals can be sent without loss or distortion over arbitrary distances. Think of all the digital systems people use on a daily basis: CDs are digitized audio, many cable systems are now digital, and the Internet cannot be overlooked. Then there is the telephone, which was one of the earliest experiments in digital technology.

Zeros and ones are not just the building blocks of the future—they are also the building blocks of the present.

It was not always so, of course. Telephony was initially all analog, and signal processing was not even a discipline. Social changes and increased mobility in the 1950s threatened to break the telephone system by swamping its capacity. Rescue came by way of digital technology and its increased capacity and quality. Telephone companies invested in the new digital technology to transmit digitized voices over long distances and, in doing so, laid the foundation for the long-distance data transmission so critical to the Internet. ...