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Connection tarpit on outbound (spamming)

Hi guys,

Sorry if it has been discussed before. But I am really looking forward to having the ability to use connection tarpit as used in Sendmail. (aka ratecontrol).

This is quite fundamentally different in characteristic than "Recipients per hour"

In fact, to combat with "Outgoing spamming", this ratecontrol is more effective. Outgoing spamming have a very constant pattern of sending spam (and virus) via continuous rate.

Sendmail ratecontrol IS - a tarpitting concept. Once the rate is reached , an IP must wait a time delay before ANY new connection is to be accpted

Recipient control IS - a queuing concept. Once there is an "free" ticket in the last hour, your connection will be accpted and IRpt will try to deliver as it should be.

With the "continuous" spamming in mind. The sendmail thing is more effective.

We use both here.

Any comment here from all the gurus?


Re: Connection tarpit on outbound (spamming)

To add a note here.

1. Being able to stop outgoing spamming IS also very important, but it is quite clear that we cannot use SRBS on the dialup lines (we want to treat our customers good and fair).

By fair, we mean, one can dialup and use the line for spamming a while, but we couldn't just use SRBS (history!) to limit its outgoing because another one may dial and connect it just as normal

2. Sendmail ratecontrol window is reset if one *tries* to send again during its tarpit period. i.e. continiuous spamming will be defeated after the first windowing, because subsequent spamming will keep the timer being reset.