From: les@chinet.chi.il.us (Leslie Mikesell)
Newsgroups: comp.mail.misc,comp.mail.uucp
Subject: Re: Mixed format addresses
Date: 14 Dec 92 02:14:08 GMT
Organization: Chinet - Public Access UNIX

In article <1gg7eeINNfve@gaia.ucs.orst.edu> stanley@skyking.OCE.ORST.EDU (John Stanley) writes:

>>If you want to look like part of the Internet, then get a domain name.  If
>>you don't want to play by the (easy and free) rules, then don't complain
>>that the game's no fun.

>What easy and free rule says that UUCP sites have to look like part of
>the Internet?

Rules don't have much to do with it, but if you would like most sites
to be able to reply to your mail you need a domain name.  When mail
is gatewayed among differing systems (uucp, internet, bitnet, etc.)
the return path is often damaged such that a reply is not possible
using the reverse routing information.  If you have a domain name,
the routing doesn't have to be maintained in the message.

>I can be in charge of my "little section" of the DNS? Really? From a
>UUCP site? Just what protocol do YOU know of that will allow a UUCP
>site to change the DNS records for its MX site? 

Wild-card MX records allow this.  All you have to do is maintain one
stable site to act as the gateway and have a forwarder deliver there.
For example, uunet handles MXing and forwarding for the domain *.fb.com,
delivering it to uucp site "afbf05".  As it happens, my mailer uses
fb.com as the name for all our machines and does an alias lookup to
find the right machine for delivery to each user, but if I wanted I
could let addresses go out with subdomains of .fb.com as long as my gateway
machine knows where to send the reply.

>>|You'll NEVER have the case where EVERYONE is registered in MX.
>>You mean the DNS.  Why not?  That was the original design goal.

Personally, I think that unrealistic goals are a sign of a bad design
and more effort should have been put into encapsulating addresses from
incompatible systems so the imbedded routing information could be
used.  But that's kind of irrelevant at this point...


>>It makes no sense for an Internet-only site to run pathalias; the maps are
>>of no use for them.  Therefore, the site must find a way from the Internet
>>to UUCP.  The easiest way for it to do that is an MX record.

>To do that reliably requires one MX record for every UUCP site. Passing
>mail to a gateway requires knowing one address. The latter sure seems to
>be much simpler than trying to get every UUCP in the world to register
>in a voluntary database. It is, however, less simple that expecting them
>to.

It could be really simple: each site that gateways onto the internet could
maintain a wild-card MX so sites using that gateway would automatically
have a return address under the DNS.  A little IDA sendmail header rewriting
magic could even make it happen automatically.  However, sites typically
don't want to lend their domain names to everyone who forwards mail through
them because there are usually other things associated with the name.  And
it's extra work for someone to register another name and set up the MX
so it doesn't get done except within organizations where someone is paid
to do it or in domain parks where a group of users understand the problem
and make the effort to fix it. 

Les Mikesell
  les@chinet.chi.il.us
Newsgroups: comp.mail.misc