[R-C] LEDBAT vs RTCWeb

[Randell Jesup]

On 4/10/2012 10:40 AM, Stefan Holmer wrote:
>
>
> On Tue, Apr 10, 2012 at 4:02 PM, Randell Jesup <randell-ietf at jesup.org
> <mailto:randell-ietf at jesup.org>> wrote:
>     As do I.  Also, I *REALLY* worry about the interaction of LEDBAT
>     flows and rtcweb flows...  If it targets 100ms queuing delay as the
>     "I'm out of the way of TCP" level, that could seriously negatively
>     impact us (and general VoIP as well, but even more so us, since
>     we'll again get driven into the ground trying to keep the queues
>     drained.  It may take longer, but LEDBAT flows tend to be
>     close-to-infinite I would assume.
>     If it targets 25ms, that's less problematic I suspect.
>
>     I'm not saying I know there will be a problem here, but that I fear
>     there will be since LEDBAT has a non-0 queuing target - it may
>     "poison the waters" for any delay-based algorithm that wants to
>     target a lower number.
>
>
> Yes, having two algorithms with different delay targets compete should
> be approximately the same thing as having a delay-based algorithm
> compete with a loss-based algorithm, although the effects seen may be
> more or less bad depending on how close the targets are. To be clear,
> our draft (draft-alvestrand-rtcweb-congestion) has a 0 delay target,
> which means that it will always let the queues drain before increasing
> the rate.

Right - which means someone should raise this issue about LEDBAT ASAP. 
Which WG is handling it?



-- 
Randell Jesup
randell-ietf at jesup.org