EPDM bandwidth saving

I have this little problem that some of our engineers would like to have possibility of remote connection to the vault and get the licensing. Because of that we've made virtual lan for our staff but the problem is their upstream bandwidth. Downloads from the vault are good, worse when they try to upload whole assembly or even whole project. It takes like ages till the process is finished and the status bar isnt perfect because it counts the number of files without their size - we have largest files starting to copy on 99%. So i thought You(solidworks community) might be able to help me find the answer. If vault stores the info about document history of versions and modifications is it possible to change the policy to transfering only the changes to the vault? We're still at 2009th releses though...

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