When a resource-limited device (such as a mobile telephone) joins a network associated with an enterprise, the agent in the device generates digital signatures for all the files in the device and sends them to an enterprise controller. The controller compares them to the global signature database; it filters out the sensitive digital signatures and feeds them back to the agent in the device. The agent receives the feedback of digital signatures and consolidates them into its own local signature database. The agent analyzes each file that is attempting to be output from the device according to the local signature database and DLP policy. If the signature of the file is present in the local database then the action to output file is blocked. If a new file is created on the device, the agent generates and sends its digital signature to the controller for inspection. If the signature is sensitive, this new digital signature will be placed into the local signature database. If the DLP controller updates the global signature database, the device will send its signatures once again for comparison.