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Re: [nsp] known networks for broadcast ping attacks

  • From: Jay R. Ashworth
  • Date: Thu Jul 31 01:30:22 1997 
On Wed, Jul 30, 1997 at 10:15:24PM -0700, Joe Rhett wrote:
> > .255 is _always_ a broadcast address, no?
>  
> Uh, no. If the bit mask is smaller than /24, any given .255 address could
> be legitimate.

RFC 917 and RFC 922 (admittedly old) suggest strongly that this isn't a
good idea; I'm still searching to find the reference I remember that
specifically deprecates it.

I guess it matters, since I'm not aware of routers that allow the
specification of filter rule addresses with /netsizes.

Cheers,
-- jra
-- 
Jay R. Ashworth                                                [email protected]
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