How to priorize RDP traffic for incoming remote SSL clients

Question

Basically we would like to reserve some bandwidth (up & downstream) for our employees who sometimes work from their home office. We have an asymetrical bandwidth with 250MBit down & 25 MBit upstream. Sometimes we notice that for example uploads massively interfere with RDP sessions . Situations like a ftp upload eats up over 23Mbit and our sll client users complain that the RDP session to their workstation gets laggy or sometimes even get's stuck. 
 I already had a look at the "Quality of Service (QoS)" section in our SG210/UTM9 firewall but I can't really figure out how to reserve like 5MBit upstream (of our 25MBit) for RDP connections. Somehow it seems I can throttle things down but not prioritize them or reserve bandwidth at all. 
 Are there any "cooking receipts" for QoS in UTM9 out there with some typical constellations? The help page is somehow to cryptic in this section. 
 Thank you in advance for any help.

DouglasFoster · Answer

It appears that you found the traffic throttle feature but not the traffic shaping feature. UTM provides a hidden wizard, which is the easiest way to do either one: 
 
 Choose a time when there is the RDP traffic occurring. 
 On the Dashboard, look in the upper right where UTM shows the current bandwidth in and out for each interface. 
 Click on one of those objects to view current activity. If your RDP traffic is arriving on a VPN tunnel, you probably want to use the OUT object on the INTERNAL interface. 
 The pop-up window will be empty at first. Be patient and after a few seconds the tabular data will display. 
 The table shows every active applications and its network usage. To the right of each row is a button for Block, Shape, or Throttle. If you click Shape or Throttle, you will get a pop-up asking for the parameters to apply. Throttle has no guaranteed minimum bandwidth, shaping does. 
 UTM creates all of the related objects when you save your settings. 
 
 Also recommend reading RFC 3449, which gets into the theory of how Asymmetric-speed networks can experience performance problems. I don't know how to tune UTM based on that document, but the Linux stuff underneath probably has a way to do so.