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	id 0wrlfj-0000Zf-00; Fri, 25 Jul 1997 08:48:47 -0600
To: Terry Lambert <terry@lambert.org>
Subject: Re: (over)zealous mail bouncing 
Cc: jas@flyingfox.com (Jim Shankland), Anthony.Kimball@East.Sun.COM,
        current@freebsd.org
In-reply-to: Your message of "Thu, 24 Jul 1997 16:21:00 PDT."
		<199707242321.QAA18495@phaeton.artisoft.com> 
References: <199707242321.QAA18495@phaeton.artisoft.com>  
Date: Fri, 25 Jul 1997 08:48:47 -0600
From: Warner Losh <imp@rover.village.org>
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In message <199707242321.QAA18495@phaeton.artisoft.com> Terry Lambert writes:
: Reverse Address Resoloution Protocol.  When someone connects to me,
: I can always geet the IP address they are connecting from.  Using
: RARP, I can turn the address into a machine name, and compare it
: with what you tell me on the "HELO" and "MAIL FROM:" lines.

Terry, that's complete bullshit.  RARP is a protocol used on the
ethernet for booting workstations ask for their IP address.  Much like
ARP.

Turning IP -> DNS name is just a DNS lookup.

Warner