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Did the computer scientist at Xerox really develop the first LAN, but had no backing from the company to further develop these technologies, later showing this to both Steve Jobs and Bill Gates?

Just for reference, it is in reference to this story.

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    Again, without a definition what consists a LAN in context of this question, there weill be no useful answer. Networks between computers have been available since the 1950s. – Raffzahn Apr 15 at 16:52
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    I think it is false to claim that Xerox did not back Ethernet or that it did not participate in its further development. – Ken Gober Apr 15 at 18:47
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Xerox developed ethernet. Was there a local area network preceding ethernet?

There was certainly wide area networking before ethernet, e.g. ARPANET dating from 1969.

There was also local networking even earlier, e.g. the IBM 1401, sold as a small mainframe in its own right, also ended up being used as a peripheral controller for larger mainframes; this arrangement could be called a network. But one feels it was not quite the same thing. So what was novel about the Xerox LAN?

Ethernet was designed to be a purely local network among peer workstations. And I think the Xerox Alto was the first general-purpose workstation in the sense that term came to be used.

So if you use the term LAN in that particular sense, I think the answer is yes, ethernet was the first.

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    ARCNET was developed during the same period as Ethernet and released the same year, 1976. ALOHA was from 1971, predating both. ALOHA directly inspired Ether. ALOHA, however, was not captive to a wire and was very wide area. – Maury Markowitz Apr 15 at 21:03
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    @MauryMarkowitz - this should a an answer - because it is. – Peter M. - stands for Monica Apr 15 at 21:43
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    What about DECnet? " Originally released in 1975 in order to connect two PDP-11 minicomputers, it evolved into one of the first peer-to-peer network architectures" (Wikipedia). – No'am Newman Apr 16 at 8:00
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    Phase I was not a LAN, but basically a glorified serial cable.Phase II was a LAN, but was not released until 1978 (the wiki is wrong). IBM's SNA was about the same time too, but I don't know if it was peer-to-peer until later, it was mostly about connecting – Maury Markowitz Apr 16 at 15:46
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    Dang! I wanted to say "Chaosnet," but the Wikipedia article says that they got the idea from Xerox. – Solomon Slow Sep 9 at 14:59
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Xerox developed the Ethernet, which is a LAN, but most likely not the first LAN.

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    Care to discuss what you think was the first lan. – Neil Meyer Apr 16 at 6:45
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    @NeilMeyer The NPL network is an obvious counterexample to Xerox being the first, though I doubt NPL was the first either. – Sneftel Apr 16 at 8:51
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In 1968 or so the Lawrence Radiation Laboratory, with several hundred terminals and at least four "host" computers (running applications), all communicating via a central PDP-6, decided to move to a distributed networking system with more direct connections between the computers, the PDP-8 terminal concentrators and peripheral systems. This was documented in a technical report by Samuel F. Mendicino, "The Lawrence Radiation Laboratory Octopus," presented at the Courant Institute of NYU on November 30th or December 1st, 1970, several years before Bob Metcalfe started developing Ethernet.

The move towards direct communication between individual machines, rather than having all communications go through the PDP-6, was for reliability and redundancy reasons:

Two major problems with this system became apparent about two years ago. The usefulness of the hosts, the data base, the interactive terminals etc., was totally dependent on the reliability of the central (PDP-6) system. If the central CPU or memory failed (often at times) there was no network at all. If a channel between a host and PDP-6 failed the host was isolated simultaneously from the data base, user terminals, and remote I/O.

Over those two years they built protocols (which they refer to as "sub-networks") for message routing (used in cases where direct connections between two hosts wanting to communicate were not available), terminal connectivity, file sharing (including files and directories shared between users), and remote peripheral (e.g., printer and card reader) access, and were continuing development further in this direction. The report's summary:

The original centralized LRL Octopus network was abandoned in favor of an almost fully connected distributed network. The network consists of a superimposition of sub-networks, each independent of the other, performing a specific network function.

Whether you consider this a true "LAN" like Etherent depends on your definition of "LAN," but this was clearly headed in that direction.

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The way I interpret Bob Metcalfe's words in this interview, the Xerox team used a Data General local area network prior to the work on the Alto, for which Ethernet was invented.

And we started working on this personal computer and I started working on how to network them together. And the predecessor system that we had also built used Nova 800s, a product of Data General. So we had, I think, we had 32 of them all tied together in a local area network. And this was a local area network built by Data General called the MCA, Multi-Processor Communications Adaptor, which was a, I believe, a 16-bit parallel cable that ran from one machine the other and carried data among them at about 1.5 megabits per second.

So that means that Xerox did not develop the first LAN, at least not in the view of the inventors of Ethernet.

With respect to the "got no backing from the company" part of the question, that presumably refers to the whole Alto effort, for which Ethernet was developed. Xerox made copiers, not computers!

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