Distance-bounding protocol

Distance-bounding protocol

Distance bounding protocols are cryptographic protocols that enable a verifier V to establish an upper bound on the physical distance to a prover P. They are based on timing the delay between sending out a challenge bits and receiving back the corresponding response bits. The delay time for responses enables V to compute an upper-bound on the distance, as the round trip delay time divided into twice the speed of light. The computation is based on the fact that electro-magnetic waves travel nearly at the speed of light, but cannot travel faster.

Distance bounding protocols can have different applications. For example, when a person conducts a cryptographic identification protocol at an entrance to a building, the access control computer in the building would like to be ensured that the person giving the responses is no more than a few meters away.

RF Implementation

The distance bound computed by a Radio frequency distance bounding protocol is very sensitive to even the slightest processing delay. This is because any delay introduced, anywhere in the system, will be multiplied by approximately 299,792,458 m/s (the speed of light) in order to convert time into distance. This means that even delays on the order of nanoseconds will result in significant errors in the distance bound (a timing error of 1 ns corresponds to a distance error of 15 cm).

Because of the extremely tight timing constraints and the fact that a distance bounding protocol requires that the prover apply an appropriate function to the challenge sent by the verifier, it is not trivial to implement distance bounding in actual physical hardware. Conventional radios have processing times that are orders of magnitudes too big, even if the function applied is a simple XOR.

In 2010, Rasmussen and Capkun devised a way for the prover to apply a function using pure analog components [1]. The result is a circuit whose processing delay is below 1 nanosecond from receiving a challenge till sending back the response. This processing delay translates into a maximum potential distance error of 15cm.


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Distance-bounding protocol — Les Distance bounding protocols[note 1] sont des protocoles de sécurité qui permettent à un vérificateur V de s assurer qu un prouveur P se trouve à une distance bornée et définie de lui même. Ces protocoles sont issus des travaux réalisés par… …   Wikipédia en Français

  • Attaque par relais — Une attaque par relais, connu en anglais sous le nom de relay attack, est un type d attaque informatique, similaire à l attaque de l homme du milieu et l attaque par rejeu, dans lequel un attaquant ne fait que relayer mot pour mot un message d un …   Wikipédia en Français

  • Challenge-response authentication — For the spam filtering technique, see Challenge response spam filtering. For other uses, see CRAM (disambiguation). In computer security, challenge response authentication is a family of protocols in which one party presents a question (… …   Wikipedia

  • United Kingdom — a kingdom in NW Europe, consisting of Great Britain and Northern Ireland: formerly comprising Great Britain and Ireland 1801 1922. 58,610,182; 94,242 sq. mi. (244,100 sq. km). Cap.: London. Abbr.: U.K. Official name, United Kingdom of Great… …   Universalium

  • Land mine — For other uses, see Land mine (disambiguation). Minefield redirects here. For other uses, see Minefield (disambiguation). Examples of anti personnel mines. From left to right: an M14, Valmara 69 (a bounding mine), and VS 50 …   Wikipedia

  • Greece — /grees/, n. 1. Ancient Greek, Hellas. Modern Greek, Ellas. a republic in S Europe at the S end of the Balkan Peninsula. 10,583,126; 50,147 sq. mi. (129,880 sq. km). Cap.: Athens. 2. a city in W New York. 16,177. * * * Greece Introduction Greece… …   Universalium

  • Norway — /nawr way/, n. Norwegian, Norge. a kingdom in N Europe, in the W part of the Scandinavian Peninsula. 4,404,456; 124,555 sq. mi. (322,597 sq. km). Cap.: Oslo. * * * Norway Introduction Norway Background: Despite its neutrality, Norway was not able …   Universalium

  • Washington, D.C. — This article is about the place. For the novel, see Washington, D.C. (novel). Washington, D.C.   Federal district   …   Wikipedia

  • dress — /dres/, n., adj., v., dressed or drest, dressing. n. 1. an outer garment for women and girls, consisting of bodice and skirt in one piece. 2. clothing; apparel; garb: The dress of the 18th century was colorful. 3. formal attire. 4. a particular… …   Universalium