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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