On Wednesday 07 December 2005 11:44, [EMAIL PROTECTED] wrote:
> > On Tue, 2005-12-06 at 10:41 +1100, James Gray wrote:
> > I've personally seen what happens to a thin-ether (10base2) network when
> > a PC's power supply decided to send all 240VAC through the motherboard
> > and hence the network card. Goodnight Irene for everything else too.
> > However, the same machine had an AUSTel certified internal (ISA) modem -
> > the PABX it was running through was untouched.
>
> Ummmm ... when an elderly and distinguished scientist says something is
> impossible he's nearly always wrong ...
>
> A nic card has an isolating transformer rated to some 1000v between it and
> the cable. For the 240v to escape A it needs a faulty transformer on A,
> then to infect B it needs another faulty transformer on B ....
(Sorry if I've screwed up the quoting - big snippage).
I know. I'm not trying to explain it. The year was 1995, the place, MGM
Grand Casino Darwin (NT, Aust.). The result was about 15 machines on the
particular thin-ether segment got their NIC's completely fried and about 4
(maybe 5) machines on the segment also lost other internal things, like
motherboards or PSU's. Obviously the machines with dead motherboards etc had
faulty isolation transformers - they were cheap NIC's anyway ("SMC" rebadged
jobs IIRC).
They (MGM) were in the process of rolling out CAT3 STP to replace the thin
ether (the data cabling company I worked for at the time had the contract).
The faulty cards caused the PHB's to rethink their "get the cheapest NIC's
and be happy" mentality and they lashed out on 3Com cards after that. Not
that it stopped people plugging their Ethernet (RJ45) NIC's into the PABX
sockets (also RJ45...but RED) - "POP", time for another NIC.
Strangely, after all the cable had been run for the CAT3 and PABX, they
offered me a job in their IT department. I accepted on the condition I never
had to crawl through another tiny hole in a ceiling or floor cavity...the
deal was done :P
Cheers,
James
--
Anyone can hold the helm when the sea is calm.
-- Publius Syrus
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