[Bloat] [Ecn-sane] 2019-12-31 docsis strict priority dual queue patent granted

Dave Taht dave.taht at gmail.com
Fri Jan 24 03:24:42 EST 2020

Jeeze, you guys are up early. I read this stuff on the plane home from
australia, and am still a bit under the weather.

On Fri, Jan 24, 2020 at 12:01 AM Sebastian Moeller <moeller0 at gmx.de> wrote:
> Hi Jonathan,
> > On Jan 24, 2020, at 08:44, Jonathan Morton <chromatix99 at gmail.com> wrote:
> >
> >> On 24 Jan, 2020, at 7:37 am, Dave Taht <dave.taht at gmail.com> wrote:
> >>
> >> "Otherwise, this exemplary embodiment enables system configuration to
> >> discard the low-priority packet tail, and transmit the high-priority
> >> packet instead, without waiting."
> >
> > So this really *is* a "fast lane" enabling technology.  Just as we suspected.

Well, there are weasel words elsewhere in the patent, and the dualq
code for linux merely cleared a lane for L4S traffic and hardcoded the
ect(1) as an identifier. It would be good to have more data on
rtt-fairness, and on CE reordering of rfc3168 ecn packets.

I spent time dreaming up also all the ways "queue protection" could be
used against the user. Given the rigor of the l4s spec required, and
how one misbehaving application can screw it all up,  I could see
queue protection of unknown sources that can be squelched on demand
being a desirable "feature". This can be used to stop "unauthorized"
mac addresses from participating in this design as one example.

I like the idea of queue protection - there is a lot of malicious
traffic worth throttling - but without a reporting scheme to the user,
nor a means for the user to set it up, and the mechanism under the
sole control of the ISP - not so much.

My other in-flight entertainment was cory doctorow's latest piece,
which was so good I submitted it to slashdot. (

>         They seem to be setting their customers up for a head-on collision with the European Union's net neutrality rules, according to which "special services/fast lanes" are permissible under the condition thay they are realized with completely dedicated addition bandwidth. Just looking at their patent diagram there is one common input path to the classifier. So either that fast lane is not going to be a paid for fast lane, or the ISPs rolling this out will be in hot water with the respective national regulators (at least in the EU). The one chance would be to give the end-user control over the classification engine, or if the strict priority path is only used for ISP originated VoIP traffic (I seem to recall there are weasel words in the EU rules that would allow that and ISPs are doing something like that already, and I agree that it is nice to be able to field an emergency call independent of access link load).

Well, one country at a time. NN is currently quite dead in the USA,
and only a change in regime might change that, and it's unclear if any
of the candiates understand the issues. Certainly with twin subsidies
being aimed at 5G and broadband deployment in pending legislation, I
have no idea what will happen here next. I view 5G with fear, watching
frontier file for bankruptcy, also... I really wish all the fiber
being run for 5G was being run into the home instead.

> Best Regards
>         Sebastian
> >
> > - Jonathan Morton
> > _______________________________________________
> > Ecn-sane mailing list
> > Ecn-sane at lists.bufferbloat.net
> > https://lists.bufferbloat.net/listinfo/ecn-sane
Make Music, Not War

Dave Täht
CTO, TekLibre, LLC
Tel: 1-831-435-0729

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