1. A method comprising: processing updated data of an application in a headend of a digital data broadcasting system, said processing including: confirming that the application data are updated upon one of an application content update request of a subscriber terminal and application file update of a contents provider; generating signaling information of the updated application data and transmitting the signaling information; separating updated objects from non-updated objects among objects constituting the application, and updating a file system structure and contents of the application; forming a first module including the updated objects but not the non-updated objects; forming a second module including the non-updated objects but not the updated objects; updating version information of the first module but not the second module; abstracting the updated objects from the first module and storing the abstracted updated objects; generating: download data block (DDB) including the formed first second modules; download service initiate (DSI) for the formed first and second modules; and download information indication (DII) including control information for the updated objects and non-updated objects, wherein the control information in part includes updated version information obtained in the abstracting step; encoding the DSI, DII and DDB in a form of Moving Picture Experts Group (MPEG)-2 transport stream (TS) data; and transmitting the encoded DSI, DII and DDB to the subscriber terminal sequentially and periodically.