An Introduction to Mollom


An Introduction to Mollom

by Sean Corrales

When setting up a client with a new site, we usually recommend they install Mollom as a way to protect their site from spammers. Here’s some information on Mollom to get you up to speed.

What is Mollom and how does it work?

Mollom is a spam filtering service for websites. It can protect any number of contact forms, comment forms, forum posts, or anywhere else users are entering input on your website. Typically, we use Mollom with Drupal based sites but it is also available for WordPress and Joomla among others.

When Mollom is installed on your server, any content that a user submits on a protected form, whether that be a contact form or a comment, is submitted to the Mollom servers. Mollom will analyze the post and return a score of either “ham”, “spam”, or “unsure”.  When content is returned as “ham”, it is posted to your site. The end user has no idea their content has been checked for being spam as it is completely transparent to most end users.

If a piece of content is returned as “spam”, it is not posted and the user is informed that this content cannot be posted. When a piece of content is returned as unsure, Mollom will return a CAPTCHA for the user to solve. If the user solves the CAPTCHA successfully, the content will then be posted.

How effective is Mollom?

For some of our clients, Mollom is blocking upwards of 500 spam messages a day. The Mollom site boasts 99.8% efficiency which means that only 20 in 10,000 spam messages were not caught.

What happens when Mollom is wrong?

In the event that a piece of spam makes it through, you can report it back to Mollom allowing them to analyze the spam and learn from it. The entire user base of Mollom benefits from this; the more spam that Mollom learns about, the better and smarter it becomes for all users.

Free vs. paid service levels

Mollom can be used as a free service or as a paid SLA (service level agreement). Both free and paid users receive the same functionality but paid members are entitled to process higher volumes of user content and also have guaranteed up time. Most of our users have had no issue with the free service and I would only recommend a paid SLA for sites with an extremely high volume of user content being created.

The free servers are unavailable from time to time which can be problematic. When Mollom is down, all content can either be let through or blocked. We tend to let it through to make sure we don’t lose any content a user may submit but this means spam can come through, too.

All in all, even at the free level, Mollom is an invaluable service that can save you potentially hours of sifting through and deleting spam from your site. Once installed, it requires minimal attention, if any at all, to effectively protect your site from spam.

More About the Author

Sean Corrales

Lead Web Developer
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