What you're asking about is called a "network shaper" or "bandwidth shaper." I've seen versions for Windows that set up limits for people using Internet connection sharing through the PC it's installed on. However, that's usually done on an IP address or port basis. I haven't seen one that specifically limits an by application or service. If the service doesn't use a common port (e.g., it uses port 27344 which isn't officially assigned to anything [I think] as opposed to port 80, which is http) that might still be useful. Try a Google search on windows network shaper or windows bandwidth shaper