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Re: BCP38 exceptions for RFC1918 space


From: Florian Weimer <fw () deneb enyo de>
Date: Sun, 15 Aug 2010 19:02:50 +0200

* Valdis Kletnieks:

On Sun, 15 Aug 2010 18:46:49 +0200, Florian Weimer said:

And that connection that's trying to use PMTU got established across the
commodity internet, how, exactly? ;)

ICMP "fragmentation needed, but DF set" messages carry the a addresses
of intermediate routers which generate them (potentially in response
to MTU drops) as source addresses, not the IP addresses of the peers
in a connection.

If any long-haul carriers are originating ICMP packets for other people's
consumption from 1918 addresses rather than addresses in their address space,
it's time to name-n-shame so the rest of us can vote with our feet and
checkbooks.  There's no excuse for that in this day and age.

What does "originating" mean?  Creating the packets?  Or forwarding
them?


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