-----Original Message----- From: David Hiers [mailto:hiersd@gmail.com] Sent: Wednesday, January 06, 2010 10:50 AM To: Brian Johnson Cc: nanog@nanog.org Subject: Re: I don't need no stinking firewall!
Poking the dragon a bit, aren't you? Fun.
If you really look at it, there is no quantitative difference between statefull and non-statefull. A non-stateful firewall can prevent a TCP session from entering the SYN_RECEIVED state by blocking the SYN packet, so it strongly impacts session state without really trying. A statefull firewall will venture a bit deeper into the state diagram with a few more rules, but this is mostly a quantitative difference when viewed at a behavioral level -snip-
David
+1 As mentioned before, the line has substantially blurred with what current devices (routers/load balancers) can do in hardware. Brandon L. On Tue, Jan 5, 2010 at 12:16 PM, Brian Johnson <bjohnson@drtel.com> wrote:
Security Gurus, et al,
I have my own idea of what a firewall is and what it does. I also understand what statefull packet inspection is and what it does. Given this information, and not prejudging any responses, exactly what is a firewall for and when is statefull inspection useful?
Please respond on-list as I want to have some useful discourse and discussion in the clear. Flamers and Trolls will be disregarded. :)
Thank you.
- Brian
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