Re: What is GreyListing
On Wed, 21 Jul 2004 05:47, Michael Loftis <email@example.com> wrote:
> It won't work forever.... eventually spambots and virusbots will catch on
> and start retrying after being 4xx-ed but implementing it now makes you
> just harder than your neighbor to break into so for the time being they'll
> mostly leave you alone.
If you have to go through one 4xx messages to send a message then it takes
twice the network bandwidth to send a spam and more than twice the effort
(queues have to be maintained etc). If you were to require more than one 4xx
message and a longer time-out then it makes it even more work for the
spamming machine and thus reduces the volume of spam that can be sent before
the machine is put on black-lists and/or shut down.
There is no solution, there are just many ways of alleviating the problem for
us while making more problems for spammers.
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