> So you need to put link-layer knowledge in the application layer, and on anything in between the app and the network link. Your app needs some API to do this,

> So you need to put link-layer knowledge in the application layer, and on anything in between the app and the network link. Your app needs some API to do this, and it surely isn't a transparent connect(2). Well let's not lose sight of the problem being solved here. If I'm a phone operator, I don't want someone downloading bittorrent on the same cell to cause packet loss and garble my phone call so it's unusable. Throwing some packets over the fence doesn't tend to work so well when there are constraints on the magic tubes.