Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/5/84; site umd5.UUCP
Path: utzoo!linus!philabs!cmcl2!seismo!umcp-cs!cvl!umd5!zben
From: zben@umd5.UUCP
Newsgroups: net.mail
Subject: Re: Mail routing -- problems showing up
Message-ID: <708@umd5.UUCP>
Date: Thu, 8-Aug-85 16:49:30 EDT
Article-I.D.: umd5.708
Posted: Thu Aug  8 16:49:30 1985
Date-Received: Sun, 11-Aug-85 07:25:50 EDT
References: <3018@nsc.UUCP> <2875@topaz.ARPA> <4787@mit-eddie.UUCP> <1022@sdcsvax.UUCP> <1431@peora.UUCP>
Reply-To: zben@umd5.UUCP (Ben Cranston)
Organization: U of Md, CSC, College Park, Md
Lines: 54
Summary: You translate to intermediate net syntax, not final net syntax

In article <1431@peora.UUCP> jer@peora.UUCP (J. Eric Roskos) writes:
>In article ? somebody writes:
>> However, why couldn't these two be:
>>         berkeley!ihnp4!cbosgd!mark
>>         ihnp4!berkeley!mysite!myname
>>
>> The first is completely compatible with every UUCP site in the world.
>
>Because the latter example requires that "berkeley" know how to translate
>"mysite!myname" into a routing or addressing format that is correct for
>your network.  This is especially hard when the destination site is not
>on the network the UUCP gateway connects to -- i.e., when an intermediate
>network has to be used to get to the final destination network.

Maybe I'm missing something here, but it seems that in the case that an
intermediate network is used for routing, the first gateway would translate
the entire path into the syntax used for the INTERMEDIATE net, and the
second gateway would translate FURTHER to get the format required by the
third (final) network.  As an example:

Message starts out sent to:    seismo!rlgvax!umcp-cs!umd5!umd2!umuc!luser

Message transfered via UUCP until it gets to site umd5, where the
remaining address string is:   umd2!umuc!luser

Umd5 realizes that its link to umd2 is ARPA Internet, and it rewrites
the address to be:             @umd2:luser@umuc

When umd2 gets the message, it realizes that its link to umuc is BitNet,
so address is rewritten as:    luser@umuc



Actually, that's not a good example.  How about a UUCP-ARPA-UUCP one:

Message starts out sent to:   left1!left2!gatea!arp1!gateb!rite1!rite2!luser

Message transfered via UUCP until it gets to site gatea, at which point the
remaining address string is:  arp1!gateb!rite1!rite2!luser

gatea realizes that its link to arp1 is ARPA Internet, and so
gatea rewrites to ARPA form:  @arp1,@gateb,@rite1:luser@rite2

By the time gateb gets it, the address string has been reduced to the
much simpler string:          @rite1:luser@rite2

Realizing that its link to rite1 is UUCP, the gate back translates the
remaining string to UUCP:     rite1!rite2!luser

And the rest is just UUCP again.  Other than what kind of back-path this
would generate, it looks like it would work...  What am I missing here?

-- 
Ben Cranston  ...{seismo!umcp-cs,ihnp4!rlgvax}!cvl!umd5!zben  zben@umd2.ARPA