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How you can fight spam in your Lotus Notes Domino environment

Learn some techniques you can use to fight spam in your Lotus Notes Domino environment.

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If you are an administrator or developer responsible for Lotus Notes Domino, fighting spam is one of your biggest problems today. You have to take some action against it not only because it saps your systems resources but because your users expect you to. Every one of them has tools in their commercial e-mail accounts at Hotmail, Yahoo and G-Mail to deal with it so why shouldn't they at work? But you should realize that you there are different ways to take on spam in a corporation.

When fighting spam, you have a variety of options. When posed with a technical challenge we often have a tendency to try to build our own solutions working with familiar tools, but on many occasions we have to consider third party products and service providers as optional alternatives. Spam is one such occasion.

The first option you would typically look at is to implement native Domino functionality. This approach would utilize real-time black hole lists (also known as DNS blacklists), rules, agents and DLLs that use the Domino Router API.

Your second option is to purchase either an antispam appliance or an antispam software solution that runs on a gateway server.

A third option would be to go with a service provider that would filter all of your inbound mail.

In all the methods, there are four basic challenges: block the highest percentage of real spam, block the smallest percentage of genuine e-mails (known here as false positives), have minimal maintenance requirements and lastly be flexible to account for future unknown threats. Basically, you want low maintenance, high spam-kill rate and low false-positive rate along with extreme flexibility. That is the equation.

On review, the native Domino options are really quite limited. But sometimes they are enough to meet an organization's needs. The Black Hole List, for example, may work well in a small organization where spam is not a major issue, and where the problem of false-positives is not that great. My experience is that many of the lists in circulation cause a great deal of collateral damage and in some cases the list owners will even intentionally generate false positives in order to take punitive action against a particular ISP. If this route is selected you must be very careful in which lists you select.


In my opinion the way to deal with spam is to install SpamSentinel. It may not be as good for large organizations but for us (a small company with less than 20 users) it is superb. There are a very low number of false positives, mainly wrong addresses which it also captures.

It takes me about ten minutes in the morning to look at the reports it generated and release any mail incorrectly caught.

I thoroughly recommend it.

—John L.


Obviously correct identification and classification of e-mails to keep out the spam is essential. However, I support the outsourcing option due to the benefits it has for our Internet connection.

We are blocking about 7.5 million spams a month, the thought of having to build redundant, load balanced servers to classify the e-mails and have a big enough pipe, so as not to affect other Internet bound transactions, does not sound like something I want to be involved in.

Having an outsourcer take that WAN hit for us is a major benefit.

—Simon B.

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Dig Deeper on Lotus Notes Domino Antispam Software and Spam Filtering



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