[Tfug] Switches -- and hubs!

[Louis Taber]

Hi all,

The location is in Northern California near the coast.  Unlike Tucson,
Lightning is rarely an issue.  Base-T Ethernet does have isolating
transformers at both ends of the run, so ground loops are not an issue.
Lighting can be a major problem.  Building R5 or R7 at Pima West Campus was
struck by lightning once.  It was an aluminum structure -- quite conductive
and well grounded.  We still ended up with $27,000 in damage.

The problem with fiber, as almost always, was the termination.  How do you
get some one 25 miles from a small town to put the connectors on the cable.


  - Louis

ps.  If you have a 90 volt differential, someone doesn't know how to use a
meter or they forgot to connect the cable to ground at least one end.

When the Shiva (Used in the movie Tron) laser was first fired at Lawrence
Livermore Labs the ground loop current took out all of the DEC LSI-11
computers used to control the mirrors.  They then put in fiber <grin>.

On Thu, Dec 24, 2009 at 8:55 AM, Bexley Hall <bexley401 at yahoo.com> wrote:

> > Geographic constraints.  Mostly a hill.
>
> Why not fibre?  I would have been wary of copper over
> such a long *outdoor* span?  (can you spell "lightning"?)
>
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