[Bloat] Bufferbloat on 4G Connexion

[Jonathan Morton]

> On 11 Oct, 2019, at 5:56 pm, Guillaume ROBIER <grobier at icow-systems.com> wrote:
> 
> I am new to this mailing list and I discovered the bufferbloat in December 2018. I work on 4G routers and the bufferbloat is very present on this type of link (4G). I contact you today to find out if people have experimented with solutions on this type of link or have configuration suggestions, because the classic fq_codel or piece_of_cake and pie do not allow to fix the bufferbloat.

This is actually my own situation at home.  My solution is to insert Cake shapers on both upstream *and* downstream directions, and adjust their bandwidth settings according to variations in available 4G speed.  To do this I use an IQrouter, which is basically a TP-Link Archer C7 with custom firmware.

One of the difficulties with 4G in particular is that the link capacity varies a great deal according to both radio propagation conditions (weather, obstructions) and local usage by other subscribers.  That means the right bandwidth setting for the small hours of the night, when nobody is awake, will leave you with a lot of bloat in the evening, when everyone is both awake and home from school/work.  You will need to measure these trends and set up a bandwidth schedule accordingly.

 - Jonathan Morton