1. A method comprising: (a) receiving, by a device having a first file comprising a first plurality of sequences of data, a second file comprising a second plurality of sequences of data, the device creating a hash table comprising entries corresponding to successive, overlapping byte sequences within the first file; (b) comparing, by the device, hashes for each of the first plurality of sequences of data with hashes for each of the second plurality of sequences of data to identify a first sequence of data and a second sequence of data present in both the first plurality of sequences of data of the first file and the second plurality of sequences of data of the second file; and (c) establishing, by the device, a third file comprising one or more sequences of data from the second file, a representation of a location identifying a number of bytes in the third file between a predetermined byte of representation of the first sequence of data represented in the third file and a predetermined byte of representation of a second sequence of data represented in the third file, and a representation of a length identifying a number of bytes of the first sequence of data bytes matching the second sequence of data bytes.