Make Noise and Whisper: A Solution to Relay Attacks

  • Omar Choudary
  • Frank Stajano
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7114)


In this paper we propose a new method to detect relay attacks. The relay attacks are possible in many communication systems, and are easy to put in practice since the attackers don’t require any knowledge about the underlying protocols or the cryptographic keys.

So far the most practical solutions against relay attacks rely on distance-bounding protocols. These protocols can provide an estimated maximum distance between two communicating devices.

We provide a different solution that can detect a relay attack regardless of the distance between the devices. Our solution relies on introducing intentional errors in the communication, providing a kind of hop-count metric.

In order to illustrate our idea we describe two idealized example implementations and we assess their theoretical performance with simulation experiments. There are several limitations in these two examples but we hope that the ideas presented in this paper will contribute towards practical implementations against relay attacks.


Debit Card Intentional Error Honest Participant Honest Player Relay Attack 
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 2011

Authors and Affiliations

  • Omar Choudary
    • 1
  • Frank Stajano
    • 1
  1. 1.Computer LaboratoryUniversity of CambridgeCambridgeUnited Kingdom

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