treason at gnu.ai.mit.edu
treason at gnu.ai.mit.edu
Thu Dec 17 09:38:58 PST 1992
Here is parts of the article I posted regarding the legality of the use
of emf shielding. Read it carefully, and I suggest you also read the
posted document in full as well. This poses many problems to the public
in general, and the private sector in specific.
PERRY, I suggest you read this.
NACSIM 5100A is classified, as are all details of TEMPEST.
To obtain access to it, contractor must prove that there is
demand within the government for the specific type of equipment
that intend to certify. Since the standard is classified, the
contractors can not sell the equipment to non-secure governmental
agencies or the public. This prevents reverse engineering of the
standard for its physical embodiment, the Certified equipment.
By preventing the private sector from owning this anti-
eavesdropping equipment, the NSA has effectively prevented the
them from protecting the information in their computers.
A number of companies produce devices to measure the
emanations from electrical equipment. Some of these devices
are specifically designed for bench marking TEMPEST
Certified equipment. This does not solve the problem. The
question arises: how much radiation at a particular
frequency is compromising? The current answer is to refer
to NACSIM 5100A. This document specifies the emanations
levels suitable for Certification. The document is only
available to United States contractors having sufficient
security clearance and an ongoing contract to produce
TEMPEST Certified computers for the government. Further,
the correct levels are specified by the NSA and there is no
assurance that, while these levels are sufficient to prevent
eavesdropping by unfriendly operatives, equipment certified
under NACSIM 5100A will have levels low enough to prevent
eavesdropping by the NSA itself.
The accessibility of supposedly correct emanations
levels does not solve the problem of preventing TEMPEST
eavesdropping. Access to NACSIM 5100A limits the
manufacturer to selling the equipment only to United States
governmental agencies with the need to process secret
information. Without the right to possess TEMPEST ELINT
equipment manufacturers who wish to sell to the public
sector cannot determine what a safe level of emanations is.
Further those manufacturers with access to NACSIM 5100A
should want to verify that the levels set out in the
document are, in fact, low enough to prevent interception.
Without an actual eavesdropping device with which to test,
no manufacturer will be able to produce genuinely
PERRY, now I put up, now YOU SHUT UP!
treason at gnu.
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