No Subject

treason at treason at
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.[33]  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
          uncompromising equipment.

PERRY, now I put up, now YOU SHUT UP!


treason at gnu.

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