Operation to replace a file on one or more pillars in a collection.
The identification response contains a field for indicating that a responding pillar is a checksum pillar, and therefore only will be able to handle put requests with a certain checksum type.
The operation request has fields for pillar-side verification of both the file to be replaced and the new file. These checksum for the existing file is for the pillar to verify that the client has not mistaken the file for another. The checksum for the new file is for the pillar to verify that the new file was the correct one and transferred correctly.
The operation request has fields for requesting checksum calculation of the existing and new files to be sent back to the client to verify that the correct file has been ingested by the pillar.