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 cw.net) 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.
Guys, 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@mhsc.com>rmeyer@mhsc.com Internet phone: hawk.mhsc.com Personal web pages: staff<http://www.mhsc.com/~rmeyer>.mhsc.com/~rmeyer Company web-site: <http://www.mhsc.com/>www.mhsc.com ___________________________________________________ Who is John Galt? "Atlas Shrugged" - Ayn Rand