[87874] in North American Network Operators' Group
Re: BLS FastAccess internal tech needed
daemon@ATHENA.MIT.EDU (Steven M. Bellovin)
Thu Jan 12 23:09:47 2006
From: "Steven M. Bellovin" <smb@cs.columbia.edu>
To: "Fergie" <fergdawg@netzero.net>
Cc: ops.lists@gmail.com, nanog@nanog.org
In-Reply-To: (Your message of "Fri, 13 Jan 2006 03:58:23 GMT.")
<20060112.195851.1587.15308@webmail05.lax.untd.com>
Date: Thu, 12 Jan 2006 23:09:13 -0500
Errors-To: owner-nanog@merit.edu
In message <20060112.195851.1587.15308@webmail05.lax.untd.com>, "Fergie" writes
:
>
>RFC2827/BCP38?
>
The problem is that an ISP can do all the source filtering it wants,
but if it only blocks SYNs to port 25 all it takes is one unfiltered
dial-up to spoof that ISP's addresses.
--Steven M. Bellovin, http://www.cs.columbia.edu/~smb
