Re: [tcpm] ECN++: Congestion response to CE on Pure ACK

[Neal Cardwell <[e-mail]>]

On Thu, Jul 20, 2017 at 2:17 AM, Gengxuesong (Geng Xuesong)
<[e-mail]> wrote:
> Hi Neal
>
> I think it is a very interesting discussion about the interaction between BBR and ECN.
> You mentioned that " since ECN schemes typically mandate a particular cwnd response from a sender ". Do you mean that the conflict between ECN and BBR is the conflict between cwnd mode and pacing mode?
> In other word, do you think if ECN is used as a signal of modifying pacing rate, these two mechanisms may work together well?

I didn't really mean the distinction between control via cwnd vs
control via pacing rate. I meant the deeper question of whether a
congestion control algorithm should simply have a fixed back-off
response to losses (Reno, CUBIC) or ECN marks (RFC 3168, DCTCP), or
whether the algorithm should try to make an independent estimate of
the capacity available to the flow (BBR).

But if someone wants an extended discussion of BBR and ECN, I'd
suggest that this should move to a separate thread, so that this
thread can stay focused on the original issues Bob raised in this
thread.

thanks,
neal