Group: microsoft.public.exchange.admin
From: "John"
Date: Friday, November 16, 2007 11:42 AM
Subject: Re: Recipient Filtering and DHA Mitigation

Thanks.

"Alexander Zammit [MVP]" wrote in message
news:u9UUei9JIHA.5624@TK2MSFTNGP04.phx.gbl...
> Here is how to configure Tarpitting:
> http://www.exchangeinbox.com/articles/020/dirharvest.htm
>
> --
> Alexander Zammit
> WinDeveloper Software
> IMF Tune - Unleash the Full Intelligent Message Filter Power
> http://www.windeveloper.com/imftune/
>
>
> "John" wrote in message news:udq1xS8JIHA.6108@TK2MSFTNGP03.phx.gbl...
>> Exchange 2003 SP2 running on Windows 2003 R2 SP2.
>>
>> I'd like to enable Recipient Filtering and Tarpitting. Here's what I
>> know. Enable the following:
>> - Message Delivery/Recipient Filtering/Filter recipients who are not in
>> the directory
>> - SMTP virtual server/Apply Recipient Filter
>> - Restart SMTP service (not sure if this is necessary)
>>
>> Here are my questions:
>>
>> 1) Do I have to install any add-on patch to be able to enable Tarpitting?
>>
>> 2) Is enabling tarpitting achieved by adding a "TarpitTime" key (DWORD
>> value) in the registry at
>> HKLM\System\CurrentControlSet\Services\SmtpSvc\Parameters\? Is that all?
>>
>> 3) What is an acceptable (or suggested) tarpittime value?
>>
>> 4) When tarpitting and recipient filtering are both enabled, whose server
>> generates NDRs if the recipient's address is invalid? (sender's servers
>> or our server?) Note: Exchange directly answers incoming connections from
>> the internet. There's no intermediate SMTP server between Exchange and
>> senders' SMTP servers.
>>
>> Thanks.
>>
>
>