Abstract:Chandran, et al. introduce the direction of position based cryptography at CRYPTO 2009. In position based cryptography, the position of a party is used to be its unique "credential" in order to realize the cryptographic tasks, such as position based encryption, position based signature, position based key exchange and so on. Position based key exchange, as a basic primitive in position based cryptography, can be used to establish a shared key based on the position of the participant.
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