Accessing an encoded data slice in a dispersed storage network

1. A method for execution by a dispersed storage and task (DST) execution unit that includes a processor, the method comprises:

receiving a slice access request for execution by the DST execution unit, wherein the slice access request includes a read request to read a first, pre-encoded data slice from a memory of the DST execution unit and wherein the slice access request includes a write request to write a second data slice to a memory of the DST execution unit;

identifying a plurality of ordered codec algorithms by reproducing a codec algorithm identifier associated with the first pre-encoded data slice, wherein the plurality of ordered codec algorithms is identified based on at least one of: a storage unit capability, a storage set capability, a request from another storage unit, a data type, a slice size, a performance requirement, a security requirement, or system registry information;

executing the slice access request by retrieving the first pre-encoded data slice from the memory and by performing the plurality of ordered codec algorithms in a reverse order to generate a decoded data slice from the first pre-encoded data slice, wherein the slice access request is further executed by performing the plurality of ordered codec algorithms in a forward order on the second data slice to generate an encoded data slice for storage in the memory of the DST execution unit; and

generating a slice access response indicating an outcome of the slice access request.

2. The method of claim 1 , wherein the plurality of ordered codec algorithms is identified based on at least one of: a slice name or a codec algorithm identifier associated with the slice access request.

3. The method of claim 1 , wherein the slice access response includes the decoded data slice.

4. A processing system of a dispersed storage and task (DST) execution unit comprises:

at least one processor;

a memory that stores operational instructions, that when executed by the at least one processor cause the processing system to:

receive a slice access request for execution by the DST execution unit, wherein the slice access request includes a read request to read a first, pre-encoded data slice from a memory of the DST execution unit and wherein the slice access request includes a write request to write a second data slice to a memory of the DST execution unit;

identify a plurality of ordered codec algorithms by reproducing a codec algorithm identifier associated with the first pre-encoded data slice, wherein the plurality of ordered codec algorithms is identified based on at least one of: a storage unit capability, a storage set capability, a request from another storage unit, a data type, a slice size, a performance requirement, a security requirement, or system registry information;

execute the slice access request by retrieving the first pre-encoded data slice from the memory and by performing the plurality of ordered codec algorithms in a reverse order to generate a decoded data slice from the first pre-encoded data slice, wherein the slice access request is further executed by performing the plurality of ordered codec algorithms in a forward order on the second data slice to generate an encoded data slice for storage in the memory of the DST execution unit; and

generate a slice access response indicating an outcome of the slice access request.

5. The processing system of claim 4 , wherein the plurality of ordered codec algorithms is identified based on at least one of: a slice name or a codec algorithm identifier associated with the slice access request.

6. The processing system of claim 4 , wherein the slice access response includes the decoded data slice.

7. A non-transitory computer readable storage medium comprises:

at least one memory section that stores operational instructions that, when executed by a processing system of a dispersed storage network (DSN) that includes a processor and a memory, causes the processing system to:

receive a slice access request for execution by a DST execution unit, wherein the slice access request includes a read request to read a first, pre-encoded data slice from a memory of the DST execution unit and wherein the slice access request includes a write request to write a second data slice to a memory of the DST execution unit;

identify a plurality of ordered codec algorithms by reproducing a codec algorithm identifier associated with the first pre-encoded data slice, wherein the plurality of ordered codec algorithms is identified based on at least one of: a storage unit capability, a storage set capability, a request from another storage unit, a data type, a slice size, a performance requirement, a security requirement, or system registry information;

execute the slice access request by retrieving the first pre-encoded data slice from the memory and by performing the plurality of ordered codec algorithms in a reverse order to generate a decoded data slice from the first pre-encoded data slice, wherein the slice access request is further executed by performing the plurality of ordered codec algorithms in a forward order on the second data slice to generate an encoded data slice for storage in the memory of the DST execution unit; and

generate a slice access response indicating an outcome of the slice access request.