Multi-party quantum key agreement with teleportation

Abstract

Based on the technique of quantum teleportation, a new multi-party quantum key agreement protocol is proposed. In this protocol, all users first share EPR pairs via public quantum channels. Afterwards, the states of signal particles can be transferred between two adjacent users by quantum teleportation. With the help of four unitary encoding operations, all users can encode their separate secret key into the traveling quantum states. In the end, all users can derive the final shared key synchronously. The security analysis shows that the presented protocol is secure against some common attacks and completely loss tolerant.