[Babel-users] Setting ECN on Babel packets [was: Route selection...]

[Juliusz Chroboczek]

> I will be changing the hardware wifi VO queue in cerowrt 3.3.8-10 to
> be sane (2 packets rather than 128).

That's probably going to kill your throughput for high-RTT links, unless
you also fix the lack of backpressure in Linux.  It might break Babel on
networks with more than 120 nodes (the maximum number of packets that
Babel will send in a burst is roughly floor(n/60) where n is the number
of routes).

> the same test also reduced throughput by about 40% (from >10Mbit to
> ~6.5Mbit).

Please try the same on a high-RTT path.

> with *your permission* I'd like to be marking babel packets in cerowrt
> as CS6 + ECN capable.

I tried to explain to you in Brussels (over a year ago) why that's
a horrible kludge.  You're applying AQM to locally-originated data in
order to compensate for the lack of backpressure, and then falsely
asserting ECN in order to bypass the AQM policy.

-- Juliusz