[e2e] Protocols breaking the end-to-end argument

Lloyd Wood L.Wood at surrey.ac.uk
Thu Oct 29 12:43:17 PDT 2009


On 29 Oct 2009, at 18:05, Dave Eckhardt wrote:
> > Define "the market" as all the places where switched Ethernet
>> is used today, crank in some realistic shares, and tell me
>> what you get; by guess is that coax Ethernet was deployed in
>> around 10-20% of the places where twisted pair and optical
>> Ethernet LANs, MANs, and WANs are used today
>
> Now I get it:  when you wrote "Ethernet only became dominant
> when we dumped CSMA/CD for the collision-free, flow controlled,
> full duplex switches that we use today" you meant something
> like "Switches were a necessary addition to Ethernet before
> it could grow from a single-building LAN to a campus-spanning
> technology".  I buy that, because treating an entire campus
> or medium-sized company as one collision domain wouldn't have
> worked out very well.

Never mind that.

Two anecdotes from the early days of my comparatively
late PhD studies (1996 or so):

1. The networks lab was next to the artificial intelligence
lab. The AI students were cooler than we were; they dressed
better, had more funding, and had laptop computers. But,
in connecting the laptops to the Ethernet LAN, they didn't
care how a big shared Ethernet coax LAN worked. They'd
just hook up connections any old how, T off more coax,
disconnect when they were done... and often they'd bring
the network down, usually just before they locked up and
took their laptops home for the day.

Never mind collisions. Ethernet switches were necessary
just to protect against and isolate the users.

2. Everyone in networks was working on ATM, and talking
about the Next Big Thing: 25Mbps ATM to the desktop.
I kept looking at the 10Mbps Ethernet we were already
using all the time every day along with the TCP/IP
stack to do daily work on and send emails about ATM,
thinking "Something is wrong with this picture."

L.

DTN work: http://info.ee.surrey.ac.uk/Personal/L.Wood/saratoga/

<http://info.ee.surrey.ac.uk/Personal/L.Wood/><L.Wood at surrey.ac.uk>



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