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Subject: [RFC] PLPMTU Blackhole Detection
From: Sean Bruno <sbruno@ignoranthack.me>
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Date: Tue, 26 Aug 2014 06:43:15 -0700
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https://reviews.freebsd.org/D506

This patch implements an attempt to adjust the MTU/MSS of a connection
to work around poor networks that block ICMP fragmentation needed
indications.

sean

p.s. I intend on working on a full PLPMTU implementation after working
this into the tree.