Periodic Transfers is a method used to transfer information from the branch office to the central office when you don't have the need for extremely current information in the central office or their is not enough expertise in the program to support a more complex method. 

Generally two methods exist for this transfer, Destroy and Rebuild and Update. The Destroy and Rebuild method sends all cases periodically to the central office, where the old central database is renamed and a new one created. This bypasses the problem of deleted cases and acts as an offsite backup of the database, since the central office receives a snapshot of what the
branch office database looks like at the moment it is sent. The trouble with this is that a large amount of data is sent. The Update method only sends the new or changed case information. The trouble with this method is that deletes can't be sent and if the transfer fails, it is hard to figure out what should have been sent.