smurf's attack...

Fri Sep 5 15:41:00 UTC 1997

> Date:          Fri, 05 Sep 1997 14:04:17 -0600
> From:          "Michael K. Sanders" <msanders at aros.net>
> Subject:       Re: smurf's attack...
> To:            Jon Green <jcgreen at netins.net>
> Cc:            "Jordyn A. Buchanan" <jordyn at bestweb.net>, nanog at merit.edu

> In message <199709051945.OAA26522 at worf.netins.net>, Jon Green writes:
> >On Fri, 5 Sep 1997 15:24:58 -0400, jordyn at bestweb.net writes:
> >
> >>access-list XXX deny ip any 0.0.0.255 255.255.255.0
> >
> >Folks, this is a bad idea.  There are lots of completely valid IP
> >addresses out there that end in .255.  True, most of them that
> >end in .255 ARE broadcast addresses, but if people implement this
> >kind of filtering on a large scale, it really breaks classless IP.
> 
> Likewise, not all broadcast adresses necessarily end with .255, 
> so filtering .255 won't help anyway in the presence of something
> like a /25 with a X.X.X.127 broadcast.

Agreed but it is not easy for a hacker to determine CIDR masks.  It
is my impression that the only thing being sent is classfull broadcasts.
> 
> 
> 
> 

Dave Nordlund               d-nordlund at ukans.edu
University of Kansas        913/864-0450
Computing Services          FAX 913/864-0485
Lawrence, KS  66045         KANREN