No Subject

Re the Phiber Optik case. I understand that only vanilla, split-band
modems (1200, 2400 baud) were tapped, on the analog loop. They were,
and still are, common in the mundane telco world.  Throw a bandpass
filter on the upper half of the audio band, get the answer data. Throw
a filter on the lower half, get the originate data. Much MUCH easier
than tapping modern full-duplex full-band modems with echo
cancellation and compression. I know some of the datacops involved,
and I seriously doubt they have a clue about how to handle V.32
without help from the NSA, which DOES know how to intercept them.

Of course, even if the modems had NSA-proof encryption built in, the
victim could always intercept the decrypted data on the DTE
connector...  cracking is and will remain a risky and stupid thing to
do...

An anonymous poster said:

> Of course, even if the modems had NSA-proof encryption built
> in, the victim could always intercept the decrypted data on the
> DTE connector...  cracking is and will remain a risky and
> stupid thing to do...

Most likely the DTE will be doing the encryption/decryption.  Who would
buy an expensive hardware encryption device when you can write terminal
software to do it?

Yeah, tapping 1200 and 2400 bps modems is prety easy to do.  Actually
you probably wouldn't even need to build filters or anything, just
record the signal and connect it to a stock 2400 modem, then set the
modem to originate or answer.  The modem already has filters to decode
the data, of course.  You have to do it twice if you want to get both
sides of the transmission tho.