Re: Greylisting BCP

Murray S. Kucherawy wrote:
>
>>> "greylisting is more expensive than not greylisting"
>>>
>>> Can you explain this?
>>
>> Put simply, any new filter has a cost to install, maintain, and 
>> operate.  For greylisting there has to be a local store of sources 
>> that you've seen that get to bypass greylisting, so anything not on 
>> that list gets caught.  That takes space, I/O, and processing time.  
>> So "expensive" in the resources sense.
>>
>
On the other hand, if it stops a reasonable amount of spam, it reduces 
bandwidth, processing time and storage requirements, as well as human 
time & annoyance handling the spam.

It's up to the implementer to decide whether the cost of implementing 
greylisting is more or less than the cost of not implementing it.