Covert Messaging through TCP Timestamps

  • John Giffin
  • Rachel Greenstadt
  • Peter Litwack
  • Richard Tibbetts
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2482)


Covert channels exist in most communications systems and allow individuals to communicate truly undectably. However, covert channels are seldom used due to their complexity. A protocol for sending data over a common class of low-bandwidth covert channels has been developed. The protocol is secure against attack by powerful adversaries. The design of a practical system implementing the protocol on a standard platform (Linux) exploiting a channel in a common communications system (TCP timestamps) is presented. A partial implementation of this system has been accomplished.


Hash Function Transmission Control Protocol Shared Secret Occupation Number Packet Header 
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 2003

Authors and Affiliations

  • John Giffin
    • 1
  • Rachel Greenstadt
    • 1
  • Peter Litwack
    • 1
  • Richard Tibbetts
    • 1
  1. 1.Massachusetts Institute of TechnologyUSA

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