A method for authenticating permission to perform an operation on a joint account, wherein the joint account is jointly managed by N joint managers, N is a natural number greater than 1, and wherein the method is performed by client software and comprises: obtaining , from each of the N joint managers, a respective joint management authentication parameter of the joint account; restoring , based on each of the joint management authentication parameters, a corresponding part of a user-side authentication parameter, the restoring comprising i) decrypting each joint management authentication parameter; ii) applying a reverse mapping algorithm to each decrypted joint management authentication parameter to obtain, for each decrypted joint management authentication parameter, a) a number k, where k ranges from 1 to N, b) a k-th segment of the user-side authentication parameter, and c) a (k+N)th segment of the user-side authentication parameter; combining the restored parts of the user-side authentication parameter into the user-side authentication parameter, comprising sequentially connecting the obtained segments based on their corresponding segment sequence numbers to obtain the user-side authentication parameter; and initiating an authentication request to a server by using the user-side authentication parameter, so the server performs authentication on operation permission for the joint account based on a network-side authentication parameter, wherein the network-side authentication parameter is the same as or corresponding to the user-side authentication parameter. obtaining , from each of the N joint managers, a respective joint management authentication parameter of the joint account; restoring , based on each of the joint management authentication parameters, a corresponding part of a user-side authentication parameter, the restoring comprising i) decrypting each joint management authentication parameter; ii) applying a reverse mapping algorithm to each decrypted joint management authentication parameter to obtain, for each decrypted joint management authentication parameter, a) a number k, where k ranges from 1 to N, b) a k-th segment of the user-side authentication parameter, and c) a (k+N)th segment of the user-side authentication parameter; i) decrypting each joint management authentication parameter; ii) applying a reverse mapping algorithm to each decrypted joint management authentication parameter to obtain, for each decrypted joint management authentication parameter, a) a number k, where k ranges from 1 to N, b) a k-th segment of the user-side authentication parameter, and c) a (k+N)th segment of the user-side authentication parameter; combining the restored parts of the user-side authentication parameter into the user-side authentication parameter, comprising sequentially connecting the obtained segments based on their corresponding segment sequence numbers to obtain the user-side authentication parameter; and initiating an authentication request to a server by using the user-side authentication parameter, so the server performs authentication on operation permission for the joint account based on a network-side authentication parameter, wherein the network-side authentication parameter is the same as or corresponding to the user-side authentication parameter. <EOS>