said by Cloneman:
....The only setup that works perfectly is having only 2 "classes" and limiting non-voip applications to use only at most 40% of the total upload bandwidth (downstream is less important, you can give up to 85%). This is somewhat a big compromise IMO, and is to be blamed on weird quirks I've seen with both how QoS works, and how ADSL handles congestion....
It makes sense to me that we must allow such percentages, when most ISP accounts' overall upstream bandwidth is so much less than their downstream.
Mine for example (START Advanced Cable on the Cogeco AGG POI) :
16Mbps DOWN (85% for NON-VoIP leaves 15% for VoIP)
16 x .15 = 2.4 Mbps
1Mbps UP (40% for NON-VoIP leaves 60% for VoIP)
1 x .6 = .6Mbps
(If the typical 5Mbps DSL was in use, DOWN would instead be
5Mbps x .15 = .75Mbps
, which would be more similar to the upstream than in my case.)
My gut feeling is that I could get away with reserving 10% DOWN for VoIP, and 40% for UP, on my particular account.