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From: hudson@ug.cs.dal.ca (Bruce Hudson)
Subject: Re: Proposed extensions to MX records.
Message-ID: <1991Apr4.185720.19031@cs.dal.ca>
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Organization: Math, Stats & CS, Dalhousie University, Halifax, NS, Canada
References: <1991Apr2.125820.29475@mp.cs.niu.edu> <1991Apr4.140715.22723@bohra.cpg.oz.au>
Date: Thu, 4 Apr 91 18:57:20 GMT

In article <1991Apr4.140715.22723@bohra.cpg.oz.au> als@bohra.cpg.oz.au (Anthony Shipman) writes:
>
>It sounds like you are trying to derive a closure from the DNS database, i.e.
>if A->B and B->C, both by SMTP then you want to conclude A->C in one hop.

    I do not think that closure was what is desired. At least what I wanted
was not closure but some way, using the DNS, to cause all sites other than
B (or C, but that wasn't a problem) to send mail for D to B. B should send
the mail to C. The current MX protocols do not allow this. It allows only
the first hop to be specified, not the second hop. To set this up, B has to
special case handling of messages to D in its mailer software.



-- 
Bruce A. Hudson			| HUDSON@AC.DAL.CA
UCIS, Facilities and Operations	| HUDSON@DALAC	(Bitnet)
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