black listing of web traffic

Rogelio rgamino at
Tue Feb 9 22:20:55 UTC 2010

Could it be a dns issue? Some sites trying to resolve your ip address  
and others don't?

Sent from my iPhone

On Feb 9, 2010, at 4:47 PM, Andrey Gordon <andrey.gordon at>  

> Can't find my IP on any of the black lists. Don't have any proxies.  
> Sites
> that behave poorly are consistent. That is to say that,
> would always come up without an issue, but,
> know, don't ask, students),
> would consistently take forever to come up.
> Just wanted to check of rate-limiting web clients is a common practice
> nowdays in the industry. If it's not, it's probably an unlikely  
> cause of my
> troubles...
> Thanks,
> Andrey
> -----
> Andrey Gordon [andrey.gordon at]
> On Tue, Feb 9, 2010 at 4:40 PM, Geoffrey Keating <geoffk at>  
> wrote:
>> Andrey Gordon <andrey.gordon at> writes:
>>> Hi list
>>> I have a problem that I can't seem to find a solution to yet. My  
>>> student
>>> network is being NATted out and anyone who's on that network had  
>>> troubles
>>> accessing random websites.
>>> For example, going to or would work
>> great,
>>> but would either not load or take forever to open  
>>> up.
>>> I've had that problem last week and thought I tracked it down to  
>>> the NAT
>> ip
>>> being black listed with one of the span black lists. Even though  
>>> that IP
>> is
>>> not used for mail out, that somehow seemed to affect it. Changing  
>>> it to a
>>> different one seemed to solve the problem and I got that original  
>>> address
>> of
>>> the list in the mean time. Changed it back and everything was  
>>> well, until
>>> today.
>>> Same symptoms, but now I don't see us listed anywhere.
>>> The best description of the symptoms seems to be that that IP is  
>>> rate
>>> limited or something.
>>> Anyone seen that? Are there any blacklists for web access?
>> Could it be related to the Pushdo botnet SSL traffic generation,
>> <>?
>> Perhaps you have an infected machine and so your IP is being
>> blacklisted and/or rate-limited.

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