The remote computer was already remote at home

On September 11, 1940, mathematicians at Dartmouth College entered complex-number problems into a teletype. The calculator answering them was at Bell Laboratories in New York. Results returned in less than a minute.

This is generally called the first public demonstration of remote computation. The distance was impressive, but it was not a new arrangement invented for the demonstration. Bell Labs had already designed the machine to be used from elsewhere.

The Complex Number Computer occupied a relay rack containing about 450 relays and ten crossbar switches. It was locked in a large closet and opened only for maintenance. Its users worked at three operator stations on different floors of the West Street building, each placed near a group that regularly needed complex arithmetic. Only one station could use the calculator at a time.

For Dartmouth, Bell Labs modified one of these consoles. A standard long-distance teletypewriter circuit replaced the local multiconductor cable. The terminal moved hundreds of kilometres; the basic relationship between operator and machine did not change.

That architecture followed the institution around it. The calculator was assembled from telephone switching equipment and Teletype machinery. It served engineers doing calculations for network design. Bell Labs understood a scarce central device connected to distributed users because that was already the organizing idea of a telephone exchange.

A Bell Labs history describes the Hanover event as a preview of later data transmission. It was. But the smaller precedent inside the building may be more revealing. Before remote computing became a way to reach a machine in another city, it was a way to keep an expensive machine in a closet while letting three departments share it.

The famous telephone line made the computer remote. The locked door had done so first.