Comment by Sesse__

> you have no control over buffer sizes on all the boxes between you and the receiver

You certainly do; the amount of data buffered can never be larger than the actual number of bytes you've sent out. Bufferbloat happens when you send too much stuff at once and nothing (typically the candidate to do so would be either the congestion window or some intermediate buffer) stops it from piling up in an intermediate buffer. If you just send less from userspace in the first place (which isn't a good thing to do for e.g. a typical web server, but _can_ be for this kind of video conference-like application), it can't pile up anywhere.

(You could argue that strictly speaking, you have no control over the _buffer_ sizes, but that doesn't matter in practice if you're bounding the _buffered data_ sizes.)