North American Network Operators Group
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Re: Broadcast pings.

  • From: Paul Ferguson
  • Date: Tue Dec 23 19:20:59 1997 
At 05:32 PM 12/23/97 -0600, Phil Howard wrote:

>
>When a packet arrives, take note of the interface and gateway it came from.
>Check the route tables for where a reply to this packet could be delivered.
>Don't choose only the best route, but compare where the packet came from
>with all valid reply routes (except broad defaults larger than a certain
>size that can be configured).  If the packet came from where it is valid
>to reply, then allow the packet to proceed.  If not, then discard it (an
>ICMP probably won't make it back to the right place anyway).
>

Yes. Some of us call this 'unicast RPF'.

Your point is well taken.  ;-)

- paul