Patent ID: 8762346

Claim:
A method for execution by a processing module of a computing device, the method comprises: receiving, from a requesting device, a data storage request that includes data for storage; determining, by the processing module, whether substantially identical data is currently stored in a dispersed storage network (DSN) memory as a plurality of sets of encoded data slices, wherein the identical data was encoded in accordance with a dispersed storage error encoding function to produce the plurality of sets of encoded data slices, and wherein the substantially identical data is recoverable based on a unique retrieval matrix of the plurality of sets of encoded data slices; and when the substantially identical data is stored in the DSN memory: generating, for the requesting device, a second unique retrieval matrix of the plurality of sets of encoded data slices, wherein the requesting device can recover at least a portion of the data based on the second unique retrieval matrix of the plurality of sets of encoded data slices, wherein: the unique retrieval matrix including: for a first set of encoded data slices of the plurality of sets of encoded data slices, identity of a first sub-set of encoded data slices of the first set of encoded data slices; and for a second set of encoded data slices of the plurality of sets of encoded data slices, identity of a first sub-set of encoded data slices of the second set of encoded data slices; and the second unique retrieval matrix including: for the first set of encoded data slices of the plurality of sets of encoded data slices, identity of a second sub-set of encoded data slices of the first set of encoded data slices; and for the second set of encoded data slices of the plurality of sets of encoded data slices, identity of a second sub-set of encoded data slices of the second set of encoded data slices, wherein each sub-set of encoded data slices includes a least a decode threshold number of encoded data slices.