Monitoring Bandwidth Usage

Does anyone know if there are any classes that expose information about bandwidth usage? For example, I would like to know when my Flash file is really pushing the bandwidth by loading a bunch of stuff (like images), versus when its basically sitting idle.

Now I know I can get stuff like progress events from an individual load but thats not what I mean here. I want to be able to get a current level of activity for my entire movie which is currently running…not information about a particular item which is being loaded.