Path: utzoo!attcan!uunet!husc6!mailrus!purdue!decwrl!ucbvax!LANL.GOV!cpw%sneezy
From: cpw%sneezy@LANL.GOV (C. Philip Wood)
Newsgroups: comp.protocols.tcp-ip
Subject: ICMP echo of host on undefined subnet mystery
Message-ID: <8811230026.AA03251@sneezy.lanl.gov>
Date: 23 Nov 88 00:26:07 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 33

Can some one give me a reason why I can trigger beaucoup ICMP messages on
an ethernet with just one measly icmp packet?

Configuration:
			        GW for 192.5.16 (subnets 192.5.16.32 and
			               |         192.5.16.64, mask =
			               		 255.255.255.224)
			         128.165.4.16   
                                       |
	=============================================================
	   |                                                    | 
	   |                                                    |
     128.165.4.10                                         128.165.4.4
      route (192.5.16 128.165.4.16 UG ...)
      
Scenario:

	128.165.4.10 sends exactly one icmp echo to 192.5.16.1 
	   192.5.16.1 is a bogus hostname on an undefined subnet.
	   
	128.165.4.4 sends 100* ICMP packets to 128.165.4.10
	   with a 'redirect for network to 128.165.4.16'
	   
	128.165.4.10 sends 128* ICMP 'echo' packets to 192.5.16.1
	   (via 128.165.4.16)
	   
	Remember the 'ping' program only sent ONE icmp echo packet.
	   
* these are the numbers I observed.  There could have been more.

Thanks for your consideration,

Phil Wood,  cpw@lanl.gov