BCP38 exceptions for RFC1918 space

Florian Weimer fw at deneb.enyo.de
Sun Aug 15 17:02:50 UTC 2010


* 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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