identify hostname

Roeland M.J. Meyer rmeyer at
Thu Dec 3 08:23:02 UTC 1998

At 11:32 AM 12/2/98 -0700, Pete Kruckenberg wrote:
>> I do have an access list deny for incoming destinations to *.*.*.255
>> since I do know that the only customer we have with larger than a /24
>> from us (via also happens to have nothing larger than /26 in
>> their network.  AFAIK, today, smurfers are only using *.*.*.255.  They
>> would have to track a lot more information to use others, so for now I
>> can generally expect that deny to prevent us from being an amplifier. 
>It's not difficult to find subnet broadcast addresses, since few routers
>(if they even support it) are configured to filter ICMP replies. If there
>isn't already software out there, it will take all of a few hours to add
>broadcast-finding code to the smurfing software in existence.


Why not make your down-stream fill out a *complete* IN-ADDR.ARPA file which
lists their sub-net bcast and base addresses? That way yo could use the DNS
system itself to find those addresses.
Roeland M.J. Meyer, ISOC (InterNIC RM993) 
e-mail: <mailto:rmeyer at>rmeyer at
Internet phone:
Personal web pages: staff<>
Company web-site: <>
Who is John Galt?
"Atlas Shrugged" - Ayn Rand

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