A quantum group signature scheme with reusable keys based on four-particle Cluster states

With the continuous development of quantum technology, researchers are constantly improving the research on quantum signatures. In the public-key cryptosystem, a quantum group signature scheme based on four-particle Cluster states is proposed. In this scheme, the four-particle Cluster states are used as quantum channels. The signer randomly generates his private key according to the public key generated by the group manager, and uses the private key to sign. The verifier uses the public key to verify the signature. The features of the scheme are as follows: the public key and private key can be reused, thus reducing the number of keys that need to be saved by the communication parties; The length of the message to be signed does not need to be the same as the length of the public and private keys, which increases the flexibility of the signature; The random sequence is used in the signature process to ensure the unpredictability of the key, thus improving the security of the scheme; The scheme has unforgeability and non-repudiation.