[Bloat] [Ecn-sane] [iccrg] Fwd: [tcpPrague] Implementation and experimentation of TCP Prague/L4S hackaton at IETF104

[Roland Bless]

Hi,

On 22.03.19 at 19:28 Victor Hou wrote:

> Broadcom has been deeply involved in developing the Low Latency DOCSIS
> cable industry specification that Bob Briscoe mentioned.  We concur with
> the L4S use of ECT(1).  L4S can be implemented either in a dual-queue or
> an fq implementation. SCE cannot be implemented with a dual-queue
> implementation; the only way to support it is with an fq
> implementation.  An fq implementation is incompatible with the Low
> Latency DOCSIS specification developed within the cable industry.

I don't understand your rationale here.
The basic SCE concept could be used for L4S as well.
I suggest to use an additional DSCP to mark L4S packets.
The L4S sender/receiver can simply react to the SCE
markings the same way that they now react to CE, with
the difference that it's safer to react to SCE, because
the signal is unambiguous, whereas CE would be ambiguous
(could be set by either classic AQM/ECN node or by
an L4S node).

Regards
 Roland