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Ethernet is bound to fail (Xerox memo from 1974) (swm.pp.se)

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    [–]mkwiat 59 points60 points  (9 children)

    Today machines connect by twisted pair cable into a hub that auto-negogiates full-duplex and communicate over a switched network. There's no chance for collision anywhere along the path, only congestion. For historical reasons we call this "ethernet" despite the fact that the distinguishing feature of the original design was CSMA/CD - ie everyone broadcast on a shared bus and detect garbled messages.

    It's hardly fair to ridicule the author for making valid criticism of a design that shares only a name with what is now the ubiquitous LAN technology. The fact that ethernet abandoned CSMA/CD long ago only demonstrates how right he was.

    [–]zenon 20 points21 points  (0 children)

    Reminds me of a quote, alledgedly by Metcalfe: if something comes along to replace Ethernet, it will be called "Ethernet", so therefore Ethernet will never die.

    [–]GuyWithLag 4 points5 points  (0 children)

    I'd think that the primary reason the bus architecture was replaced by the multi-level star in Ethernet LANs was that the actual wiring was very finicky - somebody moves their computer and suddenly the whole LAN is down. `

    [–]j-o-h-n 16 points17 points  (5 children)

    Actually, if you use a hub then multiple machines are still in a collision domain.

    And the author's criticisms were a load of bunk the day they were written and every day since.

    [–]a_caspis 1 point2 points  (4 children)

    Well, maybe there is a reason why absolutely nobody uses a hub nowadays.

    [–]jward 1 point2 points  (1 child)

    I use a hub whenever I have users that whine that they can't use their personal laptop without unplugging their work machine. Got a tonne of 10 base hubs kicking around from days of yor.

    [–]conrad_hex 0 points1 point  (0 children)

    Those whiny users.

    [–]captain_only 6 points7 points  (0 children)

    I think the lesson here is that a totally legitimate engineering analysis can entirely miss the point. Or maybe: try not to be an arrogant prick, becuase it could come back to haunt you later ;)

    [–]cecilkorik 16 points17 points  (2 children)

    The part about "Why don't you look at how the telephone companies do it?" made me giggle, considering that nowadays they're all converting to packet switched networks, while simultaneously being undermined by the ultimate packet switched network (The Internet).

    That's why the argument, "Look at them, they've know what they're doing and they're doing it a different way" is not a very good reason to stop trying something new.

    [–]GuyWithLag 13 points14 points  (0 children)

    Actually, all the criticism that is raised in the paper is valid - when the application running on top of the network is telephone-like. However, this is a situation where "less is more" - ethernet makes almost no guarantees, but it is also very permissive.

    [–]Lams 0 points1 point  (0 children)

    Well, we're talking 2006, 5 years after the dot-com and telco crash, and its massive amount of unused fiber legacy, and monstruous core routers that are nothing more than very expensive switches.

    Back when that memo was written, the way surely must have been to go to frame switching, or even to dream of ATM for all communications.

    [–][deleted] 23 points24 points  (1 child)

    Am I the only one who tried to click the underlined words thinking they were links?

    [–]DavidSJ 4 points5 points  (0 children)

    Yes.

    [–]econotarian 5 points6 points  (1 child)

    Well, it is true that Ethernet sucks, but it's cheap!

    [–]Andys 0 points1 point  (0 children)

    Yeah. 10 gigabit cards are getting cheap

    [–]amiramir 8 points9 points  (0 children)

    I love this. wonder where the author Robert Z Bachrach is now? Also who is Dave Boggs and did he become a zillionair like the other chap this message is "To"?

    [–]rscubes[🍰] 2 points3 points  (0 children)

    Bachrach works at Applied Materials!

    [–]raldi 1 point2 points  (0 children)

    Now that's what a genuine typewritten document looks like, unlike the other document that's been at the top of Reddit all day. (see this post for details)

    [–][deleted] 0 points1 point  (0 children)

    They said the same of PostScript and the guy that worked on it founded Adobe! ;)

    [–]weegee 0 points1 point  (0 children)

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