Re: [Bloat] number of home routers with ingress AQM

[Ryan Mounce <ryan@mounce.com.au>]

On Tue, 2 Apr 2019 at 23:35, Mikael Abrahamsson <swmike@swm.pp.se> wrote:
>
> I've read rumours about some ISPs implementing interaction with the VDSL
> DSLAM where there is an estimation of the current link-speed for each
> individual customer and then it tries to set the BNG egress shaper
> appropriately.

NBN here in Australia do this for their wholesale FTTN/B VDSL2
product, injecting the downstream and upstream sync speed into
PPPoE/DHCP requests. This still depends on the retail service
providers to make use of these attributes from their BNG to configure
the shaper.

>
> I am very happy about my FTTH solution I have now since from what I can
> see the L2 network is almost never a limiting factor (much better than my
> DOCSIS connection) so my bidirectional SQM with CAKE seems to work very
> well.
>
> Still, the HGW can never solve these problems properly, the egress shaping
> in the BNG needs to do a proper job. From what I have been told, there has
> been improvements here in the past few years.
>
> What I am more worried about is the egress shaping from the HGW. I talked
> to several vendors at BBF and they talked about ingress policing being
> commonly used on the BNG. This means no ingress shaping at all (just
> packet drops if they exceed the configured rate). I don't know about
> buffering on the HGW though and how the policed rate is set compared to
> the L2 rate the HGW can send via.

NBN is an example again. Their documented behaviour is to police
traffic in both directions. Most ISPs then shape in the downstream -
and it's up to a tightly managed (TR-069 ?) ISP HGW or a diligent end
user to shape traffic in the upstream. Many - probably even most users
have no shaping whatsoever in the upstream, only a policer.

And then there is their new FTTdp product, where it is not currently
possible to determine the real VDSL2 sync speed. If there's a drop of
rain it will resync at a lower speed in the upstream, and then
everything ends up queuing inside the supplied modem...