[Babel-users] RTT-aware branch of Babel

[Dave Taht]

On Thu, Jun 20, 2013 at 9:13 AM, Henning Rogge <hrogge at googlemail.com> wrote:
> Whats your experience how stable the RTT of a wireless link is?

It is pretty wildly variable. Powersave mode alone can induce 200ms of
latency. Loaded links can exhibit tens of seconds of latency under
load.

This is somewhat mitigated by the multicast queue being separated from
the main queues on some hardware. Further mitigated by stuff like
fq_codel and some upcoming driver work (on some hardware) But I would
expect current real world wifi networks to display "interesting" RTT
behavior.

Is there a way to extract the RTT from the babel monitoring ability?
or some other means (sounds like a wireshark decoder is in order)

one side effect of fq_codel I'm aware of is that the first packet in a
stream will tend to be delivered faster than the second and
succeeding, due to the "sparse stream" optimization.

>
> Henning
>
> On Thu, Jun 20, 2013 at 4:04 PM, Juliusz Chroboczek
> <jch at pps.univ-paris-diderot.fr> wrote:
>>> I'm pleased to announce the availability of my RTT-aware branch of
>>> babeld, which I've developed as part of an internship mentored by
>>> Juliusz and Matthieu.
>>
>> I'd like to add that while we designed the algorithm and protocol
>> extension together, the code is entirely due to Baptiste.
>>
>> The tentative plan is to get this merged into babeld-1.5.0.
>>
>> -- Juliusz
>>
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>
>
>
> --
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> set sail for the stars - Carl Sagan
>
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-- 
Dave Täht

Fixing bufferbloat with cerowrt: http://www.teklibre.com/cerowrt/subscribe.html