http://www.dnsbl.net.au/apricot2006/
dnsbl.net.au previously known as bl.reynolds.net.au
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APRICOT 01 March 2006.
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Stats
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website at http://www.dnsbl.net.au/
bl.reynolds.net.au started operating in January, 2002.
dnsbl.net.au has been operating since January, 2004.
commercial subscription model, so users generally avoid using it.
free use to not for profits, and low volume private users.
currently averaging 150 queries per second across all name servers.
10% of all queries result in a positive (listed) response.
uses rbldnsd software, which was written for rbl purposes.
self removal model, so pretty low maintenance.
aggregates data from other rbl's, and incorporates locally derived data also.

Comparisons - Blacklists Compared
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http://www.sdsc.edu/~jeff/spam/cbc.html 11 February 2006
45410 block.blars.org (too aggressive to be widely useful)
41241 t1.dnsbl.net.au
40330 dnsbl.sorbs.net (union of all results)
36391 sbl-xbl.spamhaus.org (union of all results)


Recommendations
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1. ensure all IP address space is correctly covered with reverse DNS.
2. ensure Reverse DNS response actually relates to server or client use.
3. where possible, block port 25 outgoing on dynamically allocated address space.
4. where possible, rate limit port 25 traffic on main mail server pools.
5. if possible, utilise many and various rbl services on all mail servers.
6. monitor rbl listings of your local address space, pro-actively investigate listings.
7. monitor and scan for compromised client machines, disable account if compromised.