An transaction method of digital data

Digital data seller client system, digital data purchaser transaction method of digital data according to the present invention, the client computer and that includes the digital data transaction server, wherein the digital data store on the digital data from the client system transaction to the server, sellers information, the digital data information, transaction step function information, the digital data is input; Wherein the digital data transaction server known to the digital data, information and transaction capability information of the digital data online; Step in which the digital data purchaser client system, select the authentication function from the business function information in order to use the digital data from the digital data transaction server; Wherein the digital data transaction server transmits the encrypted list of the digital data and the authentication function to the digital data purchaser client system; Sending a hooking module and the authenticating function module to which the digital data transaction server hooking the file identifier determination module, the digital data execution instruction that identifies the decryption module, the digital data for decrypting the encrypted by the digital data purchaser client system .; As including the said digital data purchaser client system, wherein the decoding step for decoding the digital data to the encryption comprising the steps of: if the digital data, the encryption to the file identifier determination module to the decryption module on the system's main memory, the necessary function module the underground steps and analyzing the loaded execution program in need loaded on the main memory, an executable program that can run the digital data is provided to the authenticating function module with the step on the main memory, the required function of the step and executing the necessary function step and the digital data that the execution program of the decoding of changing the target addresses to call the module entry point address of the authenticating function module from the execution program by the hooking module No. module Calling the case in a list of the encrypted authentication function before the execution of the step and the authenticating function module to run instead of the necessary function module to the authenticating function module invoke a step and the authenticating function module to load in the main memory is decoded by the decoding module the necessary function module is executed by calling the necessary function module by said application call in the authentication feature is whether the judgment step and the calls necessary function module belongs to the list determined to belong to the list of authenticated functions the authenticating function module If it is determined that it does not belong, and is characterized in that is configured to perform, including the step which does not execute the called necessary function module.