|Kokkuvõte||Position verification refers to protocols that allow us to unambiguously prove that a certain device is located in a certain position in space (by making use of the fact that the speed of light is limited and thus from the wrong points in space, responses cannot come fast enough). Unruh (Crypto 2014) presents a protocol that uses quantum communication and one application of a hash function.
The task of this thesis is to explore (and prove) certain improvements to the protocol of Unruh:
* Using a block cipher instead of a hash function and/or
* Having more than two verifiers that check the responses from the device.|