[SURBL-Discuss] Start an IP list to block?

Jeff Chan jeffc at surbl.org
Thu Sep 9 23:53:50 CEST 2004


On Thursday, September 9, 2004, 2:49:39 PM, System Dan Mahoney wrote:
> On Thu, 9 Sep 2004, Jeff Chan wrote:

>> On Thursday, September 9, 2004, 2:28:07 PM, Ryan Thompson wrote:
>>> However, for all we know *so far*, 219.254.32.111 could be a HA cluster
>>> of a few dozen machines, and, while there may be 200 pill spammers on
>>> that cluster, there may be 20,000 other legit sites.
>>
>>> With our current data, we can't make either determination. But, using
>>> forward zone data, we can do forward lookups, and track them in a database.
>>> Then, do forward lookups on SURBL data to get the IPs of spammers, and
>>> (algorithmically!) find correlations.
>>
>>> The programming effort to implement this would not be trivial, not to
>>> mention processing power and bandwidth, to do the initial run. The
>>> datasets (.com!) are huge. After that, we just have to periodically
>>> sample for new, removed, and changed domains, at which point the
>>> processing will be reduced.
>>
>> .com is so large and rapidly changing as to be practically
>> unknowable.  That's what I mean by "can't".
>>
>> By the time you have all of .com fully cataloged, it will have
>> changed significantly.
>>
>> Really the only ones who could collectively determine how spammy
>> a particular virtual host IP is are the domain registrars working
>> together and pooling all their registration data then resolving
>> every hostname and building a database of all the resolved IPs
>> mapped back into all of their domain names.

> That's not how DNS works.

> -Dan

Exactly my point.  It is not reverse DNS.

It would be a separate, extremely large database of all DNS
information and all registration information.  That would be the
only way to know all the domains that use a given IP address,
unless the hosting providers would give us all the information
about their virtual hosting accounts, which seems unlikely.

Jeff C.



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