[net.lan] Ethernet DAMAGE by hazardous voltages

rvdm@oce-rd2.UUCP (Ruurd van der Meer) (11/27/85)

I am wondering what measures can be taken to avoid  x-million 
dollar damage by lightning on local network cables like 
Ethernet.
                         *
                        *
                       *
                      *****
                         *
                        *
                       *
                     ***
                     **
                     *

The standard says : the shield conductor of each coaxial cable
segment shall make electrical contact with an effective EARTH-
reference at ONE point. A lightning on the other side of the
segment can destroy a lot of interface units and possibly more.
We at OCE have a lot of buildings with Ethernet in between.
An expensive solution is using optical ways to seperate.

I know there are 'spike-' or 'surge-' suppressors to be put
in coaxial cables. The one I know are for IBM (93 ohm) cabling.
Does anyone know such suppressors for Ethernet cable (50 ohm) ?
What about reflections with these suppressors ?  

All ideas to avoid lightning problems on networks are welcome!

		Ruurd van der Meer  OCE  NEDERLAND  BV
				    Netherlands// Venlo

*****************************************************************