Patent ID: 8209540

Claim:
A method of performing a secure incremental backup of user settings and data comprising: receiving, over a network, an old manifest from a host data processing system including an object map of a set of encrypted objects stored on the host system, wherein the manifest includes a digital signature for authentication; performing the following for each object to be backed up if the digital signature is valid: creating a new manifest; comparing each object to be backed up with entries in the old manifest to determine a first set of objects that are new and a second set of objects that have been modified since a previous backup associated with the old manifest was performed; computing a path hash for each of the first and second set of objects; encrypting each of the first and second set of objects; computing a content hash for each of the encrypted objects; updating the new manifest; sending each of the encrypted objects to the host system; and signing and sending the new manifest to the host system, wherein the host system deletes a third set of files which have been deleted since the previous backup was performed.