5000' ethernet?

David Kelly dkelly at hiwaay.net
Thu Jul 16 21:22:50 UTC 2009


On Thu, Jul 16, 2009 at 04:33:24PM -0400, Michael Powell wrote:
> David Kelly wrote:
> > 
> > Last sentences in last paragraph before See Also at
> > 
> http://en.wikipedia.org/wiki/Carrier_sense_multiple_access_with_collision_detection:
> > 
> > "Also, in Full Duplex Ethernet, collisions are impossible since data
> > is transmitted and received on different wires, and each segment is
> > connected directly to a switch. Therefore, CSMA/CD is not used on
> > Full Duplex Ethernet networks."
> 
> Aha! I did not know this (obviously). Learn something new every day...
> Maybe I'm getting too old for this line of work. The brain just isn't
> working the way it once did. I'm a big proponent of RTFM, but usually
> am looking at new material instead of forgetting stuff I read +20yrs
> ago. Thanks for setting me straight guys, it's better to be "in the
> know" than the other way around. Maybe time to retire.

I like my job but can think of a lot of other funner things to be doing.
There are a lot of trees out there with bark at handlebar height that
needs to be loosened with my dirtbike! Can't afford to retire until AAPL
hits $500.  :-)

As for RTFM read Lowell Gilbert's post in this thread where he points
out its mentioned in only one place in the docs that they were using the
term "CSMA/CD MAC" everywhere in the documentation no matter CSMA/CD
didn't apply when the MAC was configured Full Duplex.

So if you didn't fully grok the #include file you didn't have the proper
macro definitions to rewrite what they were saying into what they meant.
:-(

-- 
David Kelly N4HHE, dkelly at HiWAAY.net
========================================================================
Whom computers would destroy, they must first drive mad.


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