The vast bulk of users have no idea how many bytes they consume each month or the bytes generated by different applications. The schemes being advocated in this discussion require that the end users be Layer 3 engineers.
Actually, it sounds a lot like the Electric7 tariffs found in the UK for electricity. These are typically used by low income people who have less education than the average population. And yet they can understand the concept of saving money by using more electricity at night. I really think that a two-tiered QOS system such as the scavenger suggestion is workable if the applications can do the marking. Has anyone done any testing to see if DSCP bits are able to travel unscathed through the public Internet? --Michael Dillon P.S. it would be nice to see QoS be recognized as a mechanism for providing a degraded quality of service instead of all the "first class" marketing puffery.