International Business Machines Corporation
Verifying a rebuilt encoded data slice using slice verification information

Abstract:

Methods for verifying rebuilt data in a dispersed storage network (DSN). In various examples, a storage unit of the DSN receives a rebuilt encoded data slice of a set of encoded data slices and a set of corresponding integrity values. An integrity function is performed on the set of integrity values to calculate an integrity value of the set of integrity values, which is then compared to a locally stored value. If the values match, the set of integrity values is validated. Another integrity function is performed on the rebuilt encoded data slice to produce a calculated integrity value of the received encoded data slice. The encoded data slice is validated and stored when the calculated integrity value compares favorably to the corresponding value of the validated set of integrity values. Proof of authenticity information from other storage units may be employed to further validate the set of integrity values.