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Re: smurf's attack...

  • From: Jon Green
  • Date: Fri Sep 05 16:09:08 1997

On Fri, 5 Sep 1997 15:24:58 -0400, [email protected] writes:

>We're also using the following extended access list (along with
>anti-spoofing filters) to prevent smurf attacks from originating from our
>network:
>
>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.

But that's just IMHO. :)

-Jon

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