[Bloat] number of home routers with ingress AQM

[Mikael Abrahamsson]

On Tue, 2 Apr 2019, Sebastian Moeller wrote:

> I just wondered if anybody has any reasonable estimate how many 
> end-users actually employ fair-queueing AQMs with active ECN-marking for 
> ingress traffic @home? I am trying to understand whether L4S approach to 
> simply declare these as insignificant in number is justifiable?

If more than 0.01% of HGWs did this I'd be extremely surprised.

> I know in openwrt with sqm that is the default, but I have no idea about

To configure ingress shaping you actually have to know the speed and 
configure it. It's not the default. Also, it's useless if the transport 
network queues the packets at lower rate than at what you receive it. When 
I used my DOCSIS connection it routinely forwarded packets at lower rates 
than what I bought (and had configured the ingress shaper for).

> the number of devices that actually use sqm in the field; @Jonathan: 
> does evenroute have numbers you are willing to share, like total numbers 
> or % of iqrouters with ecn-marking ingress routing active?

ISP networks typically looks like this in the ISP->HGW direction:

BNG->L2->L2->HGW

This is the same regardless if it's DSL, DOCSIS, FTTH/PON or whatever. So 
shaping is done egress on BNG and it tries to send at lower rate than any 
of the L2 devices. Generally there is no ingress shaping of any kind on 
the HGW, it doesn't even know what speed the subscription is.

-- 
Mikael Abrahamsson    email: swmike at swm.pp.se