Wireless army took shape during World War I. It provided mobility and flexibility for command and control, and technical advances for the radio age. 

In many ways, the Western Front during WWI was the precursor of the Internet. Trenches were connected by miles of wires, used for telegraphy and telephone communications. To avoid outages, redundancy and multiple routes for signals were designed. You would find this similar to the cloud, in many ways, certainly also as a telephone switching office. As a member of the signals corps, you were always busy laying and repairing cable – a dangerous job under fire.

These wired communications networks worked pretty well as long as forces were static. Less so, when troops actually had to move. Contact was lost for hours or days, when formations changed or raids were conducted. Makeshift communications involved shouters, runners, pigeons and messenger dogs, semaphores, and flares.

Leaders knew the concept of wireless army and acknowledged its benefits. But there were a host of practical problems. Radios were too big to carry, frequencies were not coordinated and operators were not trained. And even when these were overcome, communications were not secure unless encoded, which created another problem. While Germans adopted radio quickly, the British were more conservative. They did not move to wireless army until the last year of the war, after they had mandated Marconi to create more practical sets. However, in the Middle East, Britain adopted radio faster because the greater distances did not make wired solutions practical.

The gradual shift to wireless army was greatly enabled by learning how to specify, manufacture and procure many rugged and reliable vacuum tubes. “MIL-SPEC” drove many advances in commercialization for the radio industry.

Wireless Army Secure Communications

Secure communications were a challenge for both wired and wireless army. On the wired side, it was easy for Germans to pickup telephone and telegraph signals from Allied networks. Germany used inductive sensors to pick up alternating current Allied signals from distance. This was because single wire cabling used a ground return, which leaked signals through the mud. This problem was solved by the ingenious invention of the Fullerphone in 1915. The Fullerphone used Direct Current signals, and also a crude form of encryption (chopping signals into time slices that had to be reassembled.)

On the radio side, the shift away from broad spark signals to narrow, single frequency oscillators made interception a bit harder. Much effort was invested in secret codes. All sides prepared and distributed code books to its wireless operators. There were extensive rules about which codes should be used, where and when. Plain text was forbidden in danger zones. Encoding and decoding messages was a time consuming, complex, but necessary activity in the absence of mechanical or electronic encryption, which was to arrive later. You can read about field codes used by American and German forces. And then, of course, there were the Choctaw Code Talkers who got their start in 1918.