Patent ID: 7979404

Claim:
A method for capturing and storing a data history of a file to enable instantaneous access to and reconstruction of any version of the file, comprising: for a first version of the file at a first location: storing a full copy of the file at a second location; generating a first byte range index at the second location; wherein the first byte range index references the entire contents of the full copy of the file; storing the first byte range index at the second location; and labeling the contents of the file referenced by the first byte range index as the first version of the file; for a second version of the file at the first location: comparing the second version of the file to the first version of the file to generate one or more delta strings associated with the second version of the file; storing the one or more delta strings associated with the second version of the file at the second location; generating a second byte range index at the second location that refers to bytes in the full copy of the file and to bytes in the one or more delta strings associated with the second version of the file; wherein the second byte range index references the entire contents of the second version of the file; storing the second byte range index at the second location; wherein storing the second byte range index does not overwrite the first byte range index; labeling the contents referenced by the second byte range index as the second version of the file; and using the second byte range index to enable instantaneous access to and reconstruction of the second version of the file without having to apply to the full copy of the file the one or more delta strings associated with the second version of the file.