On Wednesday, September 30, 2015 at 11:43:37 PM UTC-4, micky wrote:
In alt.home.repair, on Wed, 30 Sep 2015 10:26:43 -0400,
"(PeteCresswell)" wrote:

Per Don Y:
Ethernet is also a potential problem due to exposure to lightning strikes.
Consider running optical fiber to bridge buildings. Or, protect the
ethernet drop accordingly.

OK, now MakOlber's comment is starting to soak in.

Since I know nothing about fiber - but have experience with those $150
radio links described previously - it sounds like I am going to retire
the Ethernet and dedicate that conduit to coax.

Your decision seems premature. Why not run the new line in your
conduit with the ethernet and see how they both work at the same time.

I predict they will both work fine and spending 150 will be a waste of
150. In addition wired connections are more reliable and often faster
than wireless, even when the wireless specs allow for a maximum that is
just as fast as wired. Maximum is not always (rarely?) achieved.

The remaining question seems to be grounding.

From what I see, it depends on what you mean by working fine. The
focus is on the negative possibilities from using Ethernet due to
a 5 sigma event, not everyday operation. In that case, you wouldn't
see that it's not fine until it's too late. But if it were me, I
agree I'd just use a wired connection and properly protect it from lightning.
That is assuming it can be easily pulled. If you had to run new conduit,
then it would be a different story. There are already cables running
into the typical house, eg AC, phone, cable, and we live with that.