A Quantum Public-Key Cryptosystem without Quantum Channels between any Two Users Based on Quantum Teleportation

In this paper a quantum public-key cryptosystem without quantum channels between any two users based on quantum teleportation is presented. Every user shares a set of Einstein-Podolsky-Rosen (EPR) pairs with a key management center (KMC) as his or her (the public key, the private key) pairs. A user can send an encrypted message to another user using quantum teleportation technology by the help of KMC. No eavesdroppers can get the original message without being found. Moreover users can also fulfil digital signature of the message. In this cryptosystem what users need to do is only performing quantum teleportation which has been realized for many years in laboratory. So this cryptosystem is easier to be realized in practice. On the other hand it’s more robust against possible attacks.