A system and method for data backup over a network has been developed. The method includes creating a baseline copy of the data files that are to be archived. When the data is subsequently being backed up, the system checks for the presence of newly added files by comparing the sort order of the present data files with the sort order of the baseline copy. Any newly added files are then saved to the baseline copy. The system checks for any changes in existing files by comparing the hash numbers of the present data files with the hash numbers of the data files in the baseline copy. Any changed files are then merged into their corresponding data files in the baseline copy.