[aqm] Immediate ECN: Autotuning AQM for RTT

[Bob Briscoe <[e-mail]>]

Folks,

"Immediate ECN" slides:
<http://bobbriscoe.net/presents/1311ietf/1311tsvarea-iecn.pptx>
<http://bobbriscoe.net/presents/1311ietf/1311tsvarea-iecn.pdf>

PS. This talk fell off the end of the TSVAREA agenda. It's mostly 
relevant to AQM, but I didn't originally bring it to AQM, because it 
affects 3 wgs: tsvwg, aqm & tcpm.

In the AQM wg, there was dismay about CableLabs not including 
anything about ECN in DOCSIS3.1. This talk is about AQM dynamics; and 
how ECN can take out the 100ms of delay that CoDel and PIE introduce 
- it's essentially about auto-tuning for RTT.

It gives an interim recommendation for hardware designers that there 
should be a second instance of the AQM algo for ECN packets so that 
it can be configured with different parameters (think of WRED instead of RED).

Specifically, for ECN packets:
interval = 0 (for CoDel)
max_burst = 0 (for PIE)


Bob

PS. We have a paper under submission, which we can supply on request.
We plan to document this in the IETF too.




________________________________________________________________
Bob Briscoe,                                                  BT