Without incremental upload and download, messages are sent as a single piece, so if network connectivity is lost while a message is being uploaded or downloaded, transmission of the message fails. With incremental upload and download, large messages are broken into smaller message pieces. By allowing messages to be sent in smaller pieces, each message piece can be sent separately, resulting in the gradual upload or download of the message over several synchronizations. The complete message arrives at its destination once all of its message pieces have arrived.

For information on how to implement incremental uploads, see -iu option.

For information on how to implement incremental downloads, see -idl option.