Multi-party quantum key agreement with parameter-independent channels

A novel multi-party quantum key agreement protocol, where the channels are independent of parameters is proposed in this paper. The proposed multi-party quantum key agreement (MQKA) protocol utilises the non-maximally entangled Bell states with unknown parameters as quantum resources and performs the unitary operation to encode key information. In the parameters-independent channels, each party does not need to know the parameters of the channels being operated on. Compared with the previous MQKA protocols that are designed based on maximally entangled states, our protocol can work without knowing the parameters of the non-maximally entangled states which is convenient for experiments. Furthermore, security analysis shows that the proposed protocol can resist outsider and participant attacks.