[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: What is GreyListing

On Wed, 21 Jul 2004 05:47, Michael Loftis <mloftis@modwest.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.

http://www.coker.com.au/selinux/   My NSA Security Enhanced Linux packages
http://www.coker.com.au/bonnie++/  Bonnie++ hard drive benchmark
http://www.coker.com.au/postal/    Postal SMTP/POP benchmark
http://www.coker.com.au/~russell/  My home page

Reply to: