Xref: utzoo news.config:1774 news.admin:10681 news.software.b:5857
Path: utzoo!utstat!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!olivea!olivey!jerry
From: jerry@olivey.olivetti.com (Jerry Aguirre)
Newsgroups: news.config,news.admin,news.software.b
Subject: Re: Apology for repostings in alt - 2 C News bugs
Summary: news should not reject articles with its own name in the path
Message-ID: <49457@olivea.atc.olivetti.com>
Date: 25 Sep 90 18:39:47 GMT
References: <1990Sep24.220833.230@vicom.com>
Sender: news@olivea.atc.olivetti.com
Followup-To: news.config
Organization: Olivetti ATC; Cupertino, CA
Lines: 35

In article <1990Sep24.220833.230@vicom.com> lmb@vicom.com (Larry Blair) writes:
>The path contained in the reposting shows `Path: vsi1!vsi1!...'.  I'm pretty
>sure that 2.11 checked for your site in the path to prevent propagation loops.

I don't think that it should.  Checking the path to see if a site is
already listed is an optimization performed by the SENDER.  It is
important for UUCP feeds to non-leaf sites.  The real protections against
duplicates are the message ID and posting date.  Articles older than what
is retained in the history file should be discarded.

I think it is a bad idea to rely to heavily on the path because there is
no guarantee against duplicate news names.  Before someone mentions the
UUCP map project remember that is for UUCP, not news.  There are sites
that run news without UUCP and sites that just don't register.

As a specific example I was sending an aged ihave to sun.com with all
the articles from the previous day.  I monitored the articles they were
requesting (finding a minor bug in my sys line for them) and noticed
that they were also requesting articles that they should have received.
A little further investigation showed that those articles alread had
"sun" in the path so none of sun.com's neighbors were sending them to
sun.

The problem was that the "sun" in question was "sun.soe.clarkson.edu".
So, any articles originating on or passing thru the other "sun" won't
get to sun.com.  As there is no official control, or even registration,
of news sites there is no mechanism to prevent such naming clashes.
If sun.com rejected those articles then it was doing the wrong thing as
it had never seen them before.

I wonder how the small amout of overhead C news saves by not parsing the
date compares to the CPU, modem, and PEOPLE overhead spent on processing
recirculated expired articles.

				Jerry Aguirre