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From: Charles Swiger <cswiger@mac.com>
Date: Wed, 21 Apr 2004 16:35:41 -0400
To: Mike Tancsa <mike@sentex.net>
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cc: freebsd-security@freebsd.org
Subject: Re: Other possible protection against RST/SYN attacks (was Re: TCP
	RST attack
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On Apr 21, 2004, at 4:14 PM, Mike Tancsa wrote:
> What side effects if any are there?  Why is the default 64 and not 
> some other number like 255...

The default TTL gets decremented with every hop, which means that a 
packet coming in with a TTL of 255 had to be sent by a directly 
connected system.  [ip_ttl is an octet, so it can't hold a larger TTL 
value.]  A packet with a TTL of 64 could have been many hops away.

-- 
-Chuck