Howard C. Berkowitz
hcb at gettcomm.com
Tue Dec 2 21:54:32 UTC 2003
At 9:06 PM -0500 11/26/03, David Lesher wrote:
>Speaking on Deep Background, the Press Secretary whispered:
>> My company is investigating the use of wireless in a couple of our
>> conference rooms. Aside from limiting the scope of reception with various
>> directional antennae, does anyone have any suggestions or pointers for
>> other ways to limit the propagation of signals (i.e. special shielding
>> paint, panels or other wall coatings)?
>As I told Andy, you need a "RayProof" or similar brand shielded
>conference room. This is Faraday Cage, with a tight-fighting door,
>I don't know what they cost, but I've installed one or 2. Outside
>of labor, I suppose they might be in the $50-500K range or so,
>for small (12'x6') ones.
>Note it's a PITA to keep tight; as the door needs very
>You'll need to bring phone/Ethernet in over fiber,
>but that's not hard.
If you do put one in, and your local laws don't prevent smoking, make
it an absolutely no-smoking area. Ventilation tends not to be
I was once attending a Federal Telecommunications Standards Committee
meeting, where we were displaced from our regular conference room and
given a SCIF vault/conference room. It was stuffy enough as we met
for a couple of hours, but as we adjourned, the NSA representative
lit a cigar.
That's when we found out that the vault door was jammed.
No simple cipherlock. Full combination lock. Trust me. Do not ever
get in a mostly-sealed room with a dead cigar and some smoke
remnants. When we got out, maybe two hours later, our faces matched
the government green  walls. If this hadn't been in the
then-Defense Communications Agency headquarters with resident
locksmiths, I don't know how long we'd have been there!
Seriously, give ventilation a lot of thought. You'll need ducts with
grounded screening and lots of 90-degree bends.
Also, consider having a kick-out panel for emergency escape. Even
without high-security locks, I've seen the gasketed doors get stuck
just in shielded labs. Think of fire protection -- you really don't
want a fire suppression gas release in a vault.
 I believe the proper descriptor for that shade of green is "gang".
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