Someone had simply learned how to speak its language.… At the back of a small municipal office stood a machine that everyone assumed had become useless. It was a bulky Group 3 fax machine, beige with age, its LCD display dimming slightly whenever the fluorescent lights flickered. The office had moved almost entirely to computers and network printers, yet the fax remained connected to an old telephone line because several government agencies still occasionally sent documents that way. One evening, Kenji, the office’s systems engineer, was asked to dispose of it. Instead, he became curious. He knew that a conventional fax machine did not simply wait for “a document” to arrive. A Group 3 fax negotiates with another fax machine using a sequence of signals defined by ITU-T T.30. It establishes the connection, exchanges capabilities, synchronizes the transmission parameters, and then receives the image...