nanog mailing list archives

Re: SMURF amplifier block list


From: Pete Ashdown <pashdown () xmission com>
Date: Wed, 15 Apr 1998 13:32:48 -0600 (MDT)

Brandon Ross said once upon a time:

On Tue, 14 Apr 1998, Stephen Sprunk wrote:

Are we really concerned about being smurfed by a /30, or even a /27?

You should be.  If I didn't have directed broadcasts turned off on my
network, it would be a very effective smurf amplifier.  Because ARIN keeps
us on a very short leash, we use the smallest subnet we can get away with
for our POPs.  Some such sites are very well connected.

We should be concerned about receiving pings floods from two single
addresses?  The the IP size of the network also figures into the nature of
the attack.  Smurfing is made easier by large subnets without
directed-broadcast turned off.  It is a lot more work to get the same
results from networks smaller than a /27.


Current thread: