nanog mailing list archives

Re: trapdoor.merit.edu and other impatient Postfix mailers everywhere (fwd)


From: "Wojtek Zlobicki" <wojtekz () idirect com>
Date: Fri, 3 Aug 2001 08:25:45 -0400


Remember in your analysis that NSI's whois is *notoriously* inaccurate,
and quite often the "owner of record" of a /16 is a service provider, and
the person you WANT to send the mail to is the admin of the company that
bought a /22 from that provider's /16.

Hint:  You ever had a hack-in attempt at your site, and tried to figure
out who owned the IP address?  How long did it take you?  Have you ever
come up empty-handed?  Good - now design a way to do that look-up several
hundred times *a second*.

But yeah, with a little bit of hand-waving, they could get the mail
to the right admin at the right company.


This isn't NSI's fault !!!  Every ISP that I have worked for that assigned a
block of 8 or more IPs properly swipped their IPs with ARIN.  If people get
lazy and just swip(spelling ?)  a /16 instead of individual blocks, ARIN
cannot be blamed.  Even the IP's for the /25 that I am on on my cable modem
at home are properly swipped to reflect the geographic region as well as my
MSO.




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