
The birth and rise of Ethernet: A history - CrankyBear
https://insights.hpe.com/articles/the-birth-and-rise-of-ethernet-a-history-1706.html
======
as-j
The article doesn't explicitly name Ron Crane, but he was instrumental to the
history of Ethernet, especially the practice engineering aspects. He passed
away last week, and the world has lost a great engineer.

[https://duckduckgo.com/?q=ron+crane+ethernet&t=ipad&ia=video...](https://duckduckgo.com/?q=ron+crane+ethernet&t=ipad&ia=videos)

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cpr
Triggered scary flashbacks to chasing down network problems with a big TDR
(time domain reflectometer--basically a way of checking connectivity by
virtually walking down the wire) on MIT's CHAOSnet thick yellow coax, climbing
around ceilings and under raised floors in building 38 (EECS) late at night,
around 1979-80.

~~~
gumby
BTW CHAOSnet used a different CSMA-based protocol than PARC Ethernet (which
used PUP, also later superseded).

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kencausey
Ron Crane and Dave Boggs visit the Xerox Alto Restoration project and show
some early ethernet gear and talk a bit about the technology:
[https://youtu.be/XhIohWr10kU](https://youtu.be/XhIohWr10kU)

~~~
agumonkey
Hehe in part 16 they telnet google.com. Time Travel.

------
ohjeez
Nothing makes me feel so old as reading something and thinking, "I was there
for this."

~~~
corford
I don't think of myself as being _that_ old (will be turning 35 soon) but my
first LAN party was done with 10BASE2 and I remember working a summer/intern
job at a factory that used a token ring network...

So either I'm in denial or you're being too hard on yourself!

[ though all bets are off if you were at PARC when they were lighting it up,
in that case... you definitely are old :) ]

~~~
peckrob
I'm just a bit older than you. In the 90s I got my first tech job while still
in high school. The company I was working for was in the middle of moving to a
new building that would have a 10Base-T network, but the current building had
10Base-2 coax.

My first week was, after getting in from school, going around to people's
offices and swapping whatever network card was in their machine for a 3C509
combo card that had base-T, base-2 and another port that I think was AUI if I
remember right. That way the transition would be easier when the new office
was ready.

At the end we had a bunch left over and my boss let me keep them. That was my
first NIC. I think I still have it somewhere. I gave some away to my friends
so we could have LAN parties. :)

~~~
tonyarkles
You are correct that the third port was AUI. I don't remember the exact
details, but early in high school I bought a box of random computer hardware
at auction for $20, and it had probably a dozen 3C509s in it. Add in a 10mbit
hub that the school threw in a dumpster... Now all my friends now had Ethernet
cards and we could start having LAN parties!

------
zkms
from
[http://ethernethistory.typepad.com/papers/EthernetPaper.pdf](http://ethernethistory.typepad.com/papers/EthernetPaper.pdf)
(1975):

> Recognizing the costliness and dangers of promising "error-free"
> communication, we refrain from guaranteeing reliable delivery of any single
> packet to get both economy of transmission and high reliability averaged
> over many packets [Metcalfe, 1973b]. Removing the responsibility for
> reliable communication from the packet transport mechanism allows us to
> tailor reliability to the application and to place error recovery where it
> will do the most good. This policy becomes more important as Ethernets are
> interconnected in a hierarchy of networks through which packets must travel
> farther and suffer greater risks.

The Ethernet CRC works at the right timescales / data rates and does not
depend on information or assumptions about above layers. It works mostly OK at
quickly knocking out packets that got grossly mangled in transit -- to avoid
bothering hosts with corrupted packets and to avoid transmitting them further
-- but that's it. There's no retransmissions, no acknowledgement/negative-
acknowledgement mechanisms, no negotiating, no dependence on address schemes.
Implementing the physical layer's error correction/detection mechanisms in a
minimal way appropriate to _that_ specific physical medium was a master stroke
of design. This sort of end-to-end aware design gave higher layers freedom to
do what they wish (in terms of latency or reliability) but also let the
Ethernet frame standard remain useful for networks far beyond 10Base5.

Some Ethernet switches are in a great hurry and don't want to wait to fully
receive (and CRC-check) an incoming frame before starting to output it. They
start outputting a frame as soon as they know _where_ to output it: when
they've finished hearing the full destination MAC address. This is kinda iffy,
because the switch hasn't seen the end of the frame, so it can't know the CRC
value of the incoming frame! How are they to cope with a corrupt inbound
packet, if they've already started transmitting it out? There's no way to undo
transmitting it, so the switch takes the next best approach -- spitefully
ruining the outgoing frame, by setting its CRC field to something
_intentionally incorrect_. It'll never checksum right, and will be discarded
at the first device capable of doing so.

~~~
kijiki
Your description of cut-through switching isn't quite correct.

If the packet is corrupted, there is no need for the switch to intentionally
break the CRC, since the only way it knew the packet was corrupted in the
first place was the broken CRC. Modifying the existing, broken CRC, would
create a small chance of accidentally "fixing" the corrupted packet, whereas
just continuing to forward it would ensure that a later (store-and-forward)
switch, or the end-host would detect the broken CRC and discard the packet.

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gumby
Thinnet was definitely a revolutionary advancement. We wired my apartment
building on University Ave for thinnet in 1989 (when my apartment was the
first POP for the ISP TLG, though the term "ISP" hadn't yet been coined).

After the 1989 Loma Prieta earthquake ruined the driveway between the two
apartment buildings, we asked the manager if we could run thinnet under the
new driveway they were pouring. He shrugged and said, "sure" though he had no
idea what it meant; the cable simply looked harmless. A few years ago I walked
up and looked and the cable is still there emerging from the ground :-).

(How times change: people actually sought apartments in that building because
it had fast internet built in, yet when they would ask the manager about it he
had no idea what they were talking about)

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js2
There was a brief period of time in the mid-90s before 100 Mbps ethernet where
FDDI made an appearance:

[https://en.m.wikipedia.org/wiki/Fiber_Distributed_Data_Inter...](https://en.m.wikipedia.org/wiki/Fiber_Distributed_Data_Interface)

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WalterBright
I'm astonished this happened without government funding :-)

~~~
digi_owl
Back then blue sky was seen as an investment, not an expense. These days it
seems like anything that do not produce a positive stock value tick in the
next quarter is 86ed asap.

~~~
WalterBright
Amazon, Tesla, SpaceX, etc. suggest otherwise.

