Simon Barber <[email protected]> wrote: > > I have a couple of concerns with the recommendations of this document as > they stand. Firstly - implementing AQM widely will reduce or even > possibly completely remove the ability to use delay based congestion > control in order to provide a low priority or background service.
I agree that if AQM succeeds in reducing delay, that will reduce the delay variation that "low priority" services depend upon. However, that strikes me a a problem that delay-based congestion- control services will have to deal with regardless of AQM. Wouldn't we be better off to figure out how AQMs could signal what these delay-based services actually care about? > I think there should be a recommendation that if you are implementing > AQM then you should also implement a low priority service using DSCP, > e.g. CS1. I don't follow how that could help in practice, except for the case where the AQM is implemented _very_ near the sender. (DSCP gets lost pretty quickly at Autonomous System boundaries.) > This will enable these low priority applications to continue to > work in an environment where AQM is increasingly deployed. Unlike > DSCPs that give higher priority access to the network, a background > or low priority DSCP is not going to be gamed to get better service! (I wish I believed we could get agreement to do this!) > Secondly, there is a recommendation that AQM be implemented both within > classes of service, and across all classes of service. I'm not finding this in the document: "Quality of Service" is found in Section 2.1; but that's not "class of service". "Traffic class" is found in Sections 2.1 and 4.4, neither of which mentions "across all classes." ??? > This does not make sense. Agreed. > If you are implementing AQM across multiple classes of service, then you > are making marks or drops while ignoring what class the data belongs to. Alas, that doesn't make sense either. :^( > This destroys the very unfairness that you wanted to achieve by > implementing the classes in the first place. That's a funny way to phrase it... -- John Leslie <[email protected]> _______________________________________________ aqm mailing list [email protected] https://www.ietf.org/mailman/listinfo/aqm
