Four decades after its creation, a University of Hawaii innovation remains the basis for Wi-Fi and mobile-phone transmissions
Every time you use Wi-Fi, or send a text message, or share data over an Ethernet network, you can thank scientists at the University of Hawaii.
In the late 1960s, a group of UH engineers, led by IT pioneer Norm Abramson, set out to create a low-cost data network that would let people around the state share time on the mainframe computer at the Manoa campus. The resulting technology, says Jonathan Roberts, senior licensing associate at the UH Office of Technology Transfer, is a communications protocol called ALOHAnet, which became the foundation for the ubiquitous wireless communications we have today.
Traditional data networks, like the telephone, relied on a single, completed circuit between the sender and the receiver that allowed information to flow in a steady stream. Abramson’s innovation was to break that flow into tiny packets of data that could be sent over any available circuit and reassembled into the original message at their destination.
The technology was simple. The data packets were sent wirelessly, using cheap UHF radio frequencies. When the mainframe received the packet, it would use another UHF frequency to send a confirmation to the sender’s computer. If a busy circuit blocked any packets, the sender’s computer would resend them. Even though the reliance on UHF made it slow, Abramson’s system opened the door for simple, cost-effective wireless communications.
In fact, most wireless systems are still based on the packet technology of ALOHAnet and its heirs, but neither UH nor Abramson made a fortune off it. Abramson points out it took another IT pioneer, Bob Metcalf, the co-inventor of Ethernet, to commercialize the technology. Ironically, Metcalf’s Ethernet networks originally ran on coaxial cables rather than wirelessly. Today, though, except where speed or security issues are important, hardwired local area networks are giving way again to UHF-based systems, like Wi-Fi and Bluetooth, that still rely on technology with its roots in ALOHAnet. Your 4G smartphone also works on packet- switching technology.