Trial accounts (Re: MAKE SPAM ...etc...)

Michael Dillon michael at
Thu Aug 22 16:45:31 UTC 1996

On Thu, 22 Aug 1996, Paul A Vixie wrote:

> > I doubt many (esp. large providers) will start filtering IP/SMTP
> > traffic because (1) filters suck precious CPU, (2) they'd have to
> > maintain frequently changing filter lists, (3) and they'd increase
> > potential liability for traffic monitoring/filtering.
> (1) a Null0 route works fine, and costs no additional CPU.
> (2) i'm going to start a WWW page to register "bad" nets.
> (3) several nationwide ISPs _are_ blocking moneyworld's net.

One good thing about point (2) above is that if there is an authoritative
list of bad nets run by a respected and clueful admin such as Paul is,
then it becomes much easier for admins everywhere to just download his
router config parameters automatically every week like (dare I say it?)
transferring a DNS zone file.

And since the person maintaining the list of bad nets is both clueful and
respected we could be reasonably assured that if a bad net turns good it
will promptly be removed from the list.

What concerned me was that if people add blockages to their routers when a
very visible problem occurs, over time more and more sites get blocked but
nobody will ever go in and clean them up or even check if they should be
cleaned up.

And if the net that is blocked ends up being transferred to another owner
at some point in time, then that owner now has a "contaminated" Internet
address. And the upstream NSP who allocates this address block also has a
the contamination to deal with.

However, if there is some kind of public and coordinated effort to deal
with this issue then perhaps we can avoid the contamination (by the weekly
updates) or we can at least maintain some records of who is blocking what.
If a bad site turns good then admins can be emailled or notified somehow
to remove the blockages.

Michael Dillon                   -               ISP & Internet Consulting
Memra Software Inc.              -                  Fax: +1-604-546-3049             -               E-mail: michael at

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