1. A method for achieving privilege separation, comprising: receiving an operation-applying instruction sent by a first-type client; according to the operation-applying instruction, determining whether an operation corresponding to the operation-applying instruction is able to be executed; when the operation corresponding to the operation-applying instruction is able to be executed, sending an operation-executing instruction to a second-type client, such that the second-type client obtains a privilege for executing the operation, according to the operation-executing instruction; and sending a notifying instruction to a third-type client, such that the third-type client obtains a notification that the second-type client has obtained the privilege for executing the operation.