QoS for TCP connection made by a DLL

Our Windows app asks a 3rd party DLL to make a TCP connection to a server. We need to apply QoS parameters to this TCP connection, in order to reduce latency. Any ideas on how to do that? We're open both to suggestions that involve external tools, and letting 开发者_开发技巧our app call the Windows API.

The app runs on Windows XP and newer.

If you want the "latest and greatest" QOS story from Microsoft, you need to look into qWave. The problem with qWave is that the API in only half the story. qWave allows you to "mark" the tcp flow types (video, voice, etc) for windows itself and then network administrator can create polices about what to do about it. Also qWave is not installed by default on server OSes. What you can't do with qWave is set specific DSCP bits in the network packets, the bits set are defined by the Digital Living Network Alliance (DLNA) and the WiFi Alliance Wireless Multimedia (WMM) specification.

If you require the setting of specific DSCP bits, your only option is to use the older and deprecated Traffic Control API.