Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!mcsun!cernvax!chx400!poole
From: poole@chx400.switch.ch (Simon Poole)
Newsgroups: comp.protocols.tcp-ip.domains
Subject: Re: Proposal for use of DNS to store RFC 987, etc mappings
Message-ID: <1990Jul25.211534.693@chx400.switch.ch>
Date: 25 Jul 90 21:15:34 GMT
References: <4263.648896746@nma.com> <9007251452.AA09940@janeb.cs.wisc.edu>
Reply-To: poole@chx400.switch.ch (Simon Poole)
Distribution: inet
Organization: SWITCH Zuerich, Switzerland
Lines: 27

In article <9007251452.AA09940@janeb.cs.wisc.edu> hagens@CS.WISC.EDU writes:
.....
>The zone transfer operation was designed for just such a purpose. It allows
>one to snarf a piece of the DNS tree from a server. It is possible (although
>resource intensive) to have a single site snarf ALL the 987 mappings from
>the entire DNS system. Once this data was in hand, the mapping table could
>be built. If this site was the one responsible for the worldwide tables, 
>I think table/DNS coordination would be minimized.
....
>ps. obviously, such a resource intensive operation would run infrequently.

Ah, but that's exactly the problem. The anlogue with DNS - host table just
doesn't work: if your host table is out of date, your site just looses
connectivity, if your RFC987 tables are out of date, you start injecting
messages with bad addresses into the mail system (on both sides of the
gateway) with all the problems that can cause (loops, unreplyable
messages and so on...). 

In my opinion, implementing this scheme would simply mean: no RFC987
gateways for sites without full Internet connectivity. 


-- 
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						Simon Poole
 poole@verw.switch.ch / poole@chx400.switch.ch / mcsun!chx400!poole
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