A BRIEF HISTORY OF WIRELESS TECHNOLOGIES

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Communications over wireless links have been possible for a very long time. Radios were used for communications in the late 1800s. Guglielmo Marconi demonstrated the transmission of Morse Code over wireless links for the British Post Office in 1897. In 1898, the Russian navy cruiser Africa used a wireless communications device to communicate with operators on shore. Television signals were first broadcast in 1928. The very first visual image sent over television signals was Felix the Cat. Since those times, radio communications have come a long way. Commercial radio stations, television broadcasts, cellular phone networks, satellite data-links, slow-scan amateur video transmissions, baby monitors, Unmanned Aerial Vehicles (UAV), and GPS navigation systems all use wireless technology.

The use of encryption in communications is nothing new either. In fact, it's been used for centuries to protect sensitive messages, such as those sent from Caesar to his battlefield generals. The famous Enigma cipher machine was used during World War II to encrypt radio communications. Communications for television transmissions were encrypted with VideoCipher II in 1986. VideoCipher systems often used DES for video encryption. In 2001, the National Institute of Standards and Technology (NIST) in the United States selected Rijndael as a federal replacement for DES, thus naming Rijndael the new Advanced Encryption Standard (AES). AES has been incorporated in publicly available wireless communications devices as one of the algorithms for WPA. Some attacks are now available for AES, such as timing attacks that exploit the properties of certain types of hardware. Data encryption and communications security continue to remain an active area of research to this day.

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