1. A computing device comprising: an interface for interfacing with a dispersed storage network (DSN); memory that stores operational instructions; and a processing module operably coupled to the interface and to the memory, wherein the processing module, when operable within the computing device based on the operational instructions, is configured to: detect a data transfer instruction that directs transfer of a plurality of sets of encoded data slices from a first set of storage units (SUs) to a second set of SUs via at least one of a plurality of DSN interfaces between the first set of SUs and the second set of SUs within the DSN, wherein: a data object is segmented into a plurality of data segments that includes a first data segment corresponding to a first row and a second data segment corresponding to a second row; the first data segment is dispersed error encoded to produce a first row of encoded data slices, a read threshold number of the first row of encoded data slices provides for reconstruction of the first data segment, and a write threshold number of the first row of encoded data slices provides for a successful transfer of the first row of encoded data slices; the second data segment is dispersed error encoded to produce a second row of encoded data slices, the read threshold number of the second row of encoded data slices provides for reconstruction of the second data segment, and the write threshold number of the second row of encoded data slices provides for the successful transfer of the first row of encoded data slices; the first row of encoded data slices is distributedly stored in the first set of SUs such that a first encoded data slice of the first row of encoded data slices is stored in a first SU of the first set of SUs, and a second encoded data slice of the first row of encoded data slices is stored in a second SU of the first set of SUs; the second row of encoded data slices is distributedly stored in the first set of SUs such that a first encoded data slice of the second row of encoded data slices is stored in the first SU of the first set of SUs, and a second encoded data slice of the second row of encoded data slices is stored in the second SU of the first set of SUs; determine a data transfer synchronization protocol that maintains synchronization of at least the write threshold number of the first row of encoded data slices to be transferred from the first set of SUs to the second set of SUs based on a same first transfer rate and maintains synchronization of at least the write threshold number of the second row of encoded data slices to be transferred from the first set of SUs to the second set of SUs based on a same second transfer rate; and execute the data transfer synchronization protocol to perform synchronized transfer of respective sets of the plurality of sets of encoded data slices from the first set of SUs to the second set of SUs including to perform synchronized transfer of a first set of the plurality of sets of encoded data slices during a first time based on the same first transfer rate and to perform synchronized transfer of a second set of the plurality of sets of encoded data slices during a second time based on the same second transfer rate.