Techniques are provided for de-duplication of data. In one embodiment, a system comprises de-duplication logic that is coupled to a de-duplication repository. The de-duplication logic is operable to receive, from a client device over a network, a request to store a file in the de-duplicated repository using a single storage encoding. The request includes a file identifier and a set of signatures that identify a set of chunks from the file. The de-duplication logic determines whether any chunks in the set are missing from the de-duplicated repository and requests the missing chunks from the client device. Then, for each missing chunk, the de-duplication logic stores in the de-duplicated repository that chunk and a signature representing that chunk. The de-duplication logic also stores, in the de-duplicated repository, a file entry that represents the file and that associates the set of signatures with the file identifier.