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From: GRZ027%DBNGMD21.BITNET@ucb-vax.A (Peter Sylvester +49 228 303245)
Newsgroups: net.mail.headers
Subject: Re: loop control
Message-ID: <1171@brl-smoke.ARPA>
Date: Thu, 20-Feb-86 12:34:39 EST
Article-I.D.: brl-smok.1171
Posted: Thu Feb 20 12:34:39 1986
Date-Received: Sun, 23-Feb-86 06:00:33 EST
Sender: news@brl-smoke.ARPA
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Bob:

How long do You want to keep ids of old messages in Your system?
One year? Ten years? How much disk space do You have?
Although the idea is correct it is not praticable in a large
network environment I guess.

Our local mailer has mailing lists. When messages arrive from
the outside, it knows that he must not use outside addresses.
This avoids loops in that special case.

The situation we are talking about is that we have cascades of
lists with one list pointing to the other or a loop in a list.

We should try to avoid such situations:

First, we should distinguish between general redistribution lists
i.e. with lists that have a "global" target.
Those lists should not be placed into other global lists.
The second type are more local lists that cover a local node
or a subdomain. Those lists can be contained in global lists
and can contain global list when the following procedure is used:
The list processor must have a "responsibility list", i.e a list
or an algorithm to determine what members of the target are to be
selected. A special case is a "local" redistribution list.
where message are delivered to all local members when the message
comes from outside. When the message comes from a local user
the message can be delivered to all users or to remote users only
when it is known that one of the remote users is a global lists
containing this list. Even if that is not done, the local users
will get about two copies (perhaps some more if more lists are
involved.)

In addition it would be helpful to have a centralized data base
or server that contains the names of ALL global lists.
Sometimes I get messages from anywhere that tells: Now we
a have new list here at the "white house" where You can discuss
technical things about SDI or whatever.
The general problem is that normal users will have those information
earlier than a postmaster. Then it happens that a user quits his job
etc. and the postmaster has the poor job to find out the source
of the distribution, i.e all subscriptions.

"local" redistribution lists must not be contained in that
data base. only global lists, I guess there are current about
200 global list?

Peter Sylvester GMD Bonn