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Reverse DNS RFC

When people number their networks with some 'reverse'
type logic, it makes feeding them into local sendmail
access (read 'REJECT') lists pretty simple.

See this one as an example. (Feb 2002)

For example (in no order) :
  dialup.optusnet.com.au
               da.uu.net
   dialup.connect.net.au
       dialup.uwa.edu.au

Feeding those into your refuse lists should make
no difference to anyone who is correctly using their
local smtp server.

Of course, purists would say that your mail server
should be able to handle wildcards. But I haven't seen
it made all that simple.

Anyway, with the newer DNSbl's now doing name based,
as well as IP number based, entries, I wonder whether
all ISP's should consider numbering their reverse's 
a bit smarter?

for example,
max2-ppp-28.company123.com.au
is a bit tricky to block, where
28.max2.ppp.company123.com.au

would be a simple case of blocking direct emails from
ppp.company123.com.au

Less spam, less virii, less hassles.

I know that from my point of view, reverse entries
are just something that you need to do, and that I
hadn't put alot of thought into them.

Just a thought.

People who liked the idea

Thanks to the kind network operations people who have like my suggestion.

Jan 2002 | trump.net.au | request | response | outcome |

People who hated the idea

Ah well. Can't please everyone all of the time.

dnsbl.net.au abuse [at] dnsbl [dot] net [dot] au