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CSMA/CD Ethernet was simply a best-efforts LAN, but switched Ethernet
is a QoS-capable WAN and facilities fabric as well; ever seen an
Internet Exchange Point? Big fat Ethernet switches sit at the heart of
them, passing multiple packets at a time in parallel. It's a whole
different concept of networking than the fat dumb pipe. <br>
<br>
RB<br>
<br>
Dave Eckhardt wrote:
<blockquote cite="mid:18710.1256698658@lunacy.ugrad.cs.cmu.edu"
type="cite">
<blockquote type="cite">
<pre wrap="">[...] Ethernet only became dominant when we dumped CSMA/CD for
the collision-free, flow controlled, full duplex switches that
we use today.
</pre>
</blockquote>
<pre wrap=""><!---->
In the two environments I'm familiar with, Ethernet had firmly
crowded out everything else (and there were other things: IBM
Token Ring, Corvus OmniNet, AppleTalk over PhoneNet, LattisNet,
etc.) when it was still half-duplex thin-net, which was replaced
by 10-megabit twisted-pair into hubs, *then* 100-megabit
twisted-pair into switches.
I think there were a lot of places where Ethernet was dominant
before switches... though maybe we're using different definitions
of "dominant"? I think I mean something like "more than 90% of
desktops".
Dave Eckhardt
</pre>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Richard Bennett
Research Fellow
Information Technology and Innovation Foundation
Washington, DC</pre>
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