🚀 go-pugleaf

In article <1992Oct30.064339.7319@rtfm.mlb.fl.us> luckey@rtfm.mlb.fl.us (Jon Luckey) writes:
>phr@telebit.com (Paul Rubin) writes:
>
>>A co-worker of mine brought up an interesting idea.
>>He thinks it might be very difficult to intercept data
>>by tapping a phone line of someone using a modern high
>>speed full duplex modem.
>
>I think it'd be more difficult though to compensate for
>the echos in the system.  The V.32 or V.32bis modems on the
>ends have their own training sequences to detect echos.
>a tapping modem in the middle would have to be able to
>compensate for the echos based on a handshake it had no
>part in making.  Which I think would be a much harder
>DSP problem than the normal manufactor has to cope with.

While I admit it is more technically challenging to tap
into the middle of a V.32/V.32bis session than, say, a
V.22 session, I too think that it is reasonably easy for
those with the proper equipment.  Furthermore, if the
tap happens at the _start_ of a session, (and an
intrusive tap is practical,) you could just spoof the
conversation with a pair of V.32 modems -- one talking
to the sender, one to the receiver, and a data tee on
the line connecting the modems.

		--Ken Pizzini