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From: Juliusz Chroboczek <jch@pps.univ-paris-diderot.fr>
To: bloat@lists.bufferbloat.net
Cc: Baptiste Jonglez <baptiste.jonglez@ens-lyon.fr>
Subject: [Bloat] Fwd: [Babel-users] RTT stability inside a GRE tunnel
Date: Tue, 02 Jul 2013 01:58:40 +0200	[thread overview]
Message-ID: <8738rxessv.wl%jch@pps.univ-paris-diderot.fr> (raw)
In-Reply-To: <20130701164607.GB12090@ens-lyon.fr>


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Hi,

While experimenting with the RTT-aware branch of babeld, I ran into an
odd but interesting behaviour: between two given hosts reachable over
the Internet, the RTT is more stable inside a GRE tunnel than outside.

I've measured the RTT between the two hosts (with a simple continuous
ping), both inside and outside the GRE tunnel.

The result is quite odd: the RTT has way more jitter inside the tunnel
(and is also somewhat lower) than outside.  See an excerpt of the data:

  http://ze.polyno.me/babel/ping-tunnel-oddity.png

I have absolutely no clue as to what could cause this behaviour; any
idea?

Baptiste

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       reply	other threads:[~2013-07-01 23:58 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20130701164607.GB12090@ens-lyon.fr>
2013-07-01 23:58 ` Juliusz Chroboczek [this message]
2013-07-02  0:02 ` [Bloat] " Juliusz Chroboczek
2013-07-02  4:48   ` Mikael Abrahamsson
2013-07-02 11:08     ` Baptiste Jonglez
2013-07-02 11:27       ` Mikael Abrahamsson

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