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Date: Thu, 14 Dec 2006 11:31:27 -0800
From: Julian Elischer <julian@elischer.org>
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To: Alexander Motin <mav@alkar.net>
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Cc: FreeBSD Net <freebsd-net@freebsd.org>
Subject: Re: question for TCP gurus (in ipfw)
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Alexander Motin wrote:
> Julian Elischer wrote:
>> could we do either of:
>> 1/ not set the ACK bit  and just not do the extra work. Just send a 
>> reset?
> 
> Reset packet MUST have valid sequence number. Else it will be rejected 
> as protection from DoS atack.

Andre's reference explains it very well...  thanks..