Path: utzoo!utgpu!water!watmath!clyde!att!rutgers!mit-eddie!bloom-beacon!tut.cis.ohio-state.edu!cwjcc!hal!ncoast!allbery
From: allbery@ncoast.UUCP (Brandon S. Allbery)
Newsgroups: comp.mail.uucp
Subject: Re: this might be getting out of hand...
Message-ID: <12271@ncoast.UUCP>
Date: 21 Aug 88 23:07:59 GMT
References: <3746@palo-alto.DEC.COM> <3400006@eecs.nwu.edu>
Reply-To: allbery@ncoast.UUCP (Brandon S. Allbery)
Followup-To: comp.mail.uucp
Organization: Cleveland Public Access UN*X, Cleveland, Oh
Lines: 50

As quoted from <3400006@eecs.nwu.edu> by gore@eecs.nwu.edu (Jacob Gore):
+---------------
| / comp.mail.uucp / allbery@ncoast.UUCP (Brandon S. Allbery) / Aug 16, 1988 /
| >as long as a UUCP mailer knows
| >the *next* system in the path, it doesn't have to know the other systems.
| >But domain-based (i.e. Internet non-UUCP) mailers do not use routing, so
| >they must know the actual destination site!
| 
| That's not correct.  Explicit routing does exist within the RFC-822 world:
| 
| 	@A,@B,...,@Y:user@Z
| 
| The RFC requires all names in the route to be registered domains, but I
| doubt if any mailer pays any attention to this requirement.  My machine
| just needs to know how to route to A, and then it's A's problem.  Very much
| like UUCP paths with passive routing.
+---------------

Some mailers do conform to it.  And I *do* know about explicit RFC822
routing; but it is supposed to be a last resort, *not* used commonly!
(Read your copy of RFC822.)

+---------------
| >Thus, I can send to some site
| >"foobar" that is unknown to ncoast's mailer if *I* know the path, but
| >someone on CWRU20 (if it still exists; it was a CSNet host) can't without
| >hiding the UUCP syntax from the domain-based mailer and sending the mail to
| >a CSNet/UUCP relay site.
| 
| gore 2> checkaddr -w @accuvax.nwu.edu:jacob@foobar
| @accuvax.nwu.edu:jacob@foobar:
| queueing for smtp-local: via 'accuvax.nwu.edu': '@accuvax.nwu.edu:jacob@foobar'
| OK
| gore 2> 
| 
| No problem.
+---------------

I dropped a qualifier:  it's a UUCP address (note my reference to a UUCP
relay).  Note also that some systems (including "invisible" passive-routed
systems between CWRU20 and CSNet-Relay) may decide to look at the "!" before
the "@" and proceed to botch the path.  I'm not discussing sites known to
the Internet nameservers; it's the ones that *aren't* known to them that
cause the problems, directly ("host unknown") or indirectly (the munging at
sun and rutgers).

++Brandon
-- 
Brandon S. Allbery, uunet!marque!ncoast!allbery			DELPHI: ALLBERY
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