Re: Detecting a sniffer

[blymn () awadi com AU (Brett Lymn)]

According to Mark Owens:
> During my work in 'secure' installations, we used fiber media to prevent
> the 'sniffing' of packets using inductive pickup. This kind of 'sniffer'
> can't be detected easily - 'cept by seeing it (antennas and wires running
> next to your cable, where they don't belong, is a give-away)
>
> We also used OTDRs to look for splices in the fiber.

There is a more subtle way of tapping a fibre than splicing.  If you
carefully get rid of the protective layers on the fibre and then bend
the fibre beyond it's bend radius then you will get some of the light
leaking out through the side of the fiber.  You can probably pick this
tap up with an OTDR as well but it would be a bit more difficult to
detect than a straight splice.


-- 
Brett Lymn, Computer Systems Administrator, AWA Defence Industries
===============================================================================
"It's fifteen hundred miles to Ankh-Morpork" he said.  "We've got
three hundred and sixty three elephants, fifty carts of forage, the
monsoon's about to break and we're wearing ... we're wearing ... sort
of things, like glass, only dark... dark glass things on our eyes..."
        - Terry Pratchett "Moving Pictures".