A Verifiable Multiparty Quantum Key Agreement Based on Bivariate Polynomial

Based on a point-to-point quantum key distribution protocol and classical key distribution technologies, the concept of quantum-classical key and a new multi-party quantum-classical key agreement protocol is proposed in this paper. The distributor and any one of the participants use quantum key distribution protocol to negotiate subkey, then each of the participants shares his subkey with other participants using Shamir threshold secret sharing scheme, thus each participant will sort these subkeys and his own subkey in order, and eventually get this quantum-classical key. In this protocol, a pair of function values of binary polynomials are used to ensure the authentication of sub-shares and information among participants, and Lagrange interpolation formula of unary polynomials is used to ensure the recovery of subkeys. Security analysis shows that this protocol is secure, practical and effective.