Encoding slice verification information to support verifiable rebuilding

A computer readable memory comprises:

• a first memory that stores operational instructions that, when executed by a set of storage units of a dispersed storage network (DSN), cause the set of storage units to:
• store a set of appended encoded data slices, wherein an appended encoded data slice of the set of appended encoded data slices includes an encoded data slice of a set of encoded data slices and slice verification information that is regarding the set of encoded data slices, wherein a data segment of a data object is dispersed error encoded to produce the set of encoded data slices;
• a second memory that stores operational instructions that, when executed by a rebuilding agent of the DSN, cause the rebuilding agent to:
• identify one of the set of appended encoded data slices for rebuilding;
• rebuild the encoded data slice of the one of the set of appended encoded data slices based on a decode threshold number of appended encoded data slices of the set of appended encoded data slices;
• generate current slice verification information for the rebuilt encoded data slice;
• send an appended rebuilt encoded data slice that includes the rebuilt encoded data slice and the current slice verification information to a storage unit of the set of storage units;
• and
• a third memory that stores operational instructions that, when executed by the storage unit, cause the storage unit to:
• verify the current slice verification information corresponds to the slice verification information;
• and
• when the current slice verification information corresponds to the slice verification information, store the appended rebuilt encoded data slice as a trusted rebuilt encoded data slice.