the value of reverse address lookups?

Stephen J. Wilcox steve at telecomplete.co.uk
Thu Apr 1 00:59:13 UTC 2004


On Wed, 31 Mar 2004, Douglas F. Calvert wrote:

>  I am interested in finding out what the motivation is for requiring
> valid reverse address lookups before connecting to a daemon. I have
> heard a number of different explanations, the majority of the responses
> point to history/tradition and tcpwrappers. Is there a commonly accepted
> justification for this practice?  In my opinion it does not appear to
> increase the validity of the connection. But I may be missing something
> obvious.
>  Thanks in advance...

Well, my understanding is that whilst its easy to get a domain name and some dns
its usually quite difficult to put in a ptr record, these are usually controlled
by the ISP. If they dont exist or dont match then the address is a dialup or
hijacked or something not legitimate.. I think this is mainly an smtp antispam 
thing tho altho I see your point is for any connection is general, I guess the 
same appliers to hackers as to spammers.. ?

Steve







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