Merit Network
Can't find what you're looking for? Search the Mail Archives.
  About Merit   Services   Network   Resources & Support   Network Research   News   Events   Home

Discussion Communities: Merit Network Email List Archives

North American Network Operators Group

Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical

Re: Broadcast pings.

  • From: Jay R. Ashworth
  • Date: Wed Dec 24 12:29:34 1997

On Tue, Dec 23, 1997 at 05:32:15PM -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).

Oh ghod... weren't you around, Phil, when _I_ got roundly trounced and
reviled as a clueless newbie about 3 months ago for alomst exactly the
same solution?
 
The outcome as I recall, was that the only practical thing to do was
ingress filtering at boundary routers, if they would.

Cheers,
-- jra
-- 
Jay R. Ashworth                                                jra@baylink.com
Member of the Technical Staff             Unsolicited Commercial Emailers Sued
The Suncoast Freenet      "Two words: Darth Doogie."  -- Jason Colby,
Tampa Bay, Florida             on alt.fan.heinlein              +1 813 790 7592




Discussion Communities


About Merit | Services | Network | Resources & Support | Network Research
News | Events | Contact | Site Map | Merit Network Home


Merit Network, Inc.