Donald Davies in the 1960s invisions a "communications time sharing" and "interactive computing" called packet switching.
The development of the internet from simple batch processing to ARPANET was not only in the United States. People like Donal Davies worked in parallel, and had significant influence in the development. Davies actually came up with the name “packet switching,” while his counterparts had different names for the same idea (such as Baran). Davies was motivated by the notion of interactive computing. The 1960s saw Batch processing, which was slow and tedious. Time sharing was an alternative that made costs decrease as sharing the computer was a possibility. However, packet switching was a better idea. Davies saw it as “communications time sharing.” He implemented fairness in transmitting and the use of high speed telephone lines, but Baran beat him to the idea overseas.
In 1967, Davies made the “Mark I” that would be a demonstration of packet switching to bring about funding. However, the Mark I only had one node and was limited because of funding. The GPO in the UK did not want to invest in Davies idea of packet switching, despite the second example of “Mark II” as a faster model. Davies work on packet switching had some impact on ARPANET, when he proposed his ideas to ARPA in the 60s. However, Baran had the most impact on ARPANET. In the US, Baran was motivated (and funded) by security concerns in Cold War times.
As Davies was not given the support of the GPO, he was forced to direct his research to small scale models, as described above. Later on, in 1977, the GPO finally started working on packet switching in England. They develop the International Packet Switching Services (IPSS) based on ARPANET and Telenet. Thanks to Donald Davies early work, the UK could have been on the front line of developing packet switching technologies.
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