Re: [tcpm] Problem with Low SSThresh (was I-D Action: draft-ietf-tcpm-newcwv-03.txt)

Raffaello Secchi <r.secchi@gmail.com> Thu, 15 May 2014 10:58 UTC

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From: Raffaello Secchi <r.secchi@gmail.com>
Date: Thu, 15 May 2014 11:58:06 +0100
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Subject: Re: [tcpm] Problem with Low SSThresh (was I-D Action: draft-ietf-tcpm-newcwv-03.txt)
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Hi

We believe that low ssthresh resetting is a real problem especially in
data-limited
conditions when few packets are in flight.

We've also tried to see what happens when we drop a SYN in Linux.
In this case TCP follows the standard and drop the ssthresh to 2 MSS being
the SYN the only packet in flight.

This is a real harm for a starting connection if the SYN was dropped for
non-congestion related reasons (eg due to unsupported TCP options).


Raffaello