1204.5884 (Chong Xiang et al.)

Unicity Distance of Quantum Encryption Protocols    [PDF]

Chong Xiang, Li Yang

Shannon's concept of the unicity distance is present for classical encryption protocols, we attempt to develop it into the quantum context. Firstly we present a classification of the private key encryption protocols, there are five kinds of them. Then we present the definition of the unicity distance of encryption protocols whose plaintext space and key space are both set by classical bits and the algorithm is a quantum algorithm, we call this CCQ-unicity distance. Based on this definition we show two quantum encryption protocols whose CCQ-unicity distance is finite but much bigger than Shannon's unicity distance, and show a quantum encryption protocol with infinite CCQ-unicity distance.

View original: http://arxiv.org/abs/1204.5884