Cooperative public key generation method, and multi-party cooperative signature method and system

The invention discloses a collaborative public key generation method, and a multi-party collaborative signature method and system. The method comprises the following steps that each of N participants generates a private key of the participant; the first participant calculates a public key of the first participant according to the private key of the first participant and sends the public key of the first participant to the second participant, the second participant calculates a collaborative quasi-public key of the two participants according to the private key of the second participant and the public key of the first participant and sends the collaborative quasi-public key of the two participants to the third participant, and in a similar way, when the Nth participant receives the collaborative quasi-public keys of the N-1 participants, the collaborative quasi-public keys of the N participants are calculated according to the private key of the Nth participant and the collaborative quasi-public ...