[Dovecot] v2.2 status update: IMAP NOTIFY extension and more

[Ed W]

On 16/08/2012 08:02, Cor Bosman wrote:
>> I'm also considering implementing an SMTP submission server, which works
>> only as a proxy to the real SMTP server. The benefits of it would mainly
>> be:
> What would be really cool is if you also kept statistics on certain metrics, like how many emails a specific sender has sent. If this is done right, it could become a centralised spam sender back-off system over multiple smtp servers. Maybe something for the future. We now pay $$$$ for a commercial system that implements this.
>

Postfix allows you to write policy agents very simply.  I wrote a small 
perl utility which uses a database to count the number of emails a user 
has sent in the last 1 and 24 hours.  Based on that we throttle users (I 
have some fudging for recipients per email also). If you like the idea 
then it's about 10 lines of perl (+ a decent chunk of boiler plate).

Ed