From: "James M. Atkinson" 
Subject: [TSCM-L] {4569} STU-III Key Leakage [REPOST]
Date: 01/21/2010 06:32:27 PM

Attached is the cipher key (the whole key, not just the CIK)
leakage of a STU-III, at a distance of 10 meters due to a Blackberry
being present close to the STU. The trace on the top is the gating
signal (derived from the test equipment), and trace trace on the top is
the actual leakage of the key that was picked up over the air riding on
a Blackberry carrier signals. This is why TEMPEST is so important, and
why you need to keep a cell phone a significant distance from encryption
equipment. In this case the Blackberry was 30 cm away from the STU-III
for the test, but realistically you can do this with a BB that is 3
meters away. Remember, a spy is only looking for bits and pieces of data
from which they can derive an idea of the big picture. When they get a
high amount of data they appreciate it, but they are also happy with
fragments. When you have a Blackberry or other digital cell phone within
several meters of a STU or STE you allow the spy to collect the
fragments they are seeking, and often far more then fragments.