If they charged voice at data rates...
...it would be hideously expensive. The example noted $.005/kB for "overage". That works out to between $.30 per minute if you use DS0 (8kB/sec) rates. Typically most carriers use some adaptive coding which is 1/2 the data, so it goes to $.15 per minute which is pretty expensive for minutes. Why don't they charge the same rate for "voice" minutes as "data" minutes? Anything else is biased (usually to the detriment of the data user!). Besides "data" minutes ought to be LESS since they do not need to be "real-time" in delivery (which "voice" usually attempts to be!)
Oh, by the way, that was for one way voice. Most of the time voice is "full duplex".


