Soft Tempest: Hidden Data Transmission Using Electromagnetic Emanations

  • Markus G. Kuhn
  • Ross J. Anderson
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1525)


It is well known that eavesdroppers can reconstruct video screen content from radio frequency emanations. We discuss techniques that enable the software on a computer to control the electromagnetic radiation it transmits. This can be used for both attack and defence. To attack a system, malicious code can encode stolen information in the machine’s RF emissions and optimise them for some combination of reception range, receiver cost and covertness. To defend a system, a trusted screen driver can display sensitive information using fonts which minimise the energy of these emissions. There is also an interesting potential application to software copyright protection.


Cover Image Software Piracy Electromagnetic Emanation Screen Content Sync Pulse 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Markus G. Kuhn
    • 1
  • Ross J. Anderson
    • 1
  1. 1.University of CambridgeCambridgeUK

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