Origin Of Wireless Security: The Marconi Radio Hack Of 1903 (2017)

The date is the 4th of June 1903, and the inventor, Guglielmo Marconi, is about to demonstrate his new wireless system, which he claims can securely send messages over a long distance, without interference by tuning the signal. One of the fundamental claims of Marconi was that because his system used a tuned signal, other signals would not interfere unless they were tuned to the same frequency. The ease with which Maskelyne could monitor the signals was also an eye-opener for governments and lead to the development of wireless encryption systems that were used in World War I, II and beyond.

Source: hackaday.com