Donald Davies
lorenetworkingISP & telecom
The National Physical Laboratory scientist who arrived at the same idea independently in the mid-1960s, named it packet switching, and built a working network at NPL to prove it.
Baran had the concept and Davies gave it the word, which is not a small contribution: the term packet is what let engineers, funders and standards bodies talk about the thing without arguing about what to call it. He also did what the theory needed - an actual node, running, at Teddington - and the ARPANET design took from both men, with the terminology coming from him and the resilience argument from Baran. Independent arrival at the same answer, on two continents, is the strongest evidence that the idea was ready rather than lucky.
Also known as: davies, npl