BCP38 exceptions for RFC1918 space

Joe Greco jgreco at ns.sol.net
Mon Aug 16 11:50:00 UTC 2010

> > What does "originating" mean?  Creating the packets?  Or forwarding
> > them?
> Either way, there's no excuse.
> First off, remember that BCP38 and 1918 don't apply on your set of
> interconnected private networks, no matter how big a net it is.  You want to
> filter between two of your private nets, go ahead.  You don't want to, that's
> OK to.  The fun starts when those packets leave your network(s) and hit the
> public Internet.
> Now that we have that squared away...
> Either that intermediate router originated the ICMP 'frag needed' packet, in
> which case somebody needs to be smacked for originating a 1918-addressed packet
> on the public internet, or it's forwarding the packet.  And if it's forwarding
> the packet, then somebody *else* needs to be smacked for injecting that packet
> into the public internet.
> What *possible* use case would require a 1918-sourced packet to be traversing
> the public internet? We're all waiting with bated breath to hear this one. ;)

It's great for showing in traceroutes who the heel is.

Do I win a prize?

... JG
Joe Greco - sol.net Network Services - Milwaukee, WI - http://www.sol.net
"We call it the 'one bite at the apple' rule. Give me one chance [and] then I
won't contact you again." - Direct Marketing Ass'n position on e-mail spam(CNN)
With 24 million small businesses in the US alone, that's way too many apples.

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