One embodiment of the present invention includes a method for routing a data object (502), comprising a sequence of data units (404), to a particular component data-storage system (104-110), or particular group of component data-storage systems, within a distributed, differential electronic-data storage system (104-110, 112, 114, 116) by selecting one or more subsequences of data units (402) from the data object, computing a characteristic value from the selected subsequences, computing an index (420) from the characteristic value; and directing the data object (502) to the particular component data-storage system, or to the particular group component data-storage systems, identified by the computed index.