There are some wonderful Drupal modules that can help your site in its quest to fight spam. If you are looking to protect your email addresses from harvesting or just want to eliminate spammy posts and comments, this list is for you. Here are six of the top Drupal modules for spam prevention.
Mollom is what is referred to as an “intelligent” web service. It integrates well into a variety of websites due to the content that it monitors. Mollom will not only analyze the quality of the comments being posted to your site, but it will also scan blogs, messages in contact forms, forum posts, and more.
Mollom basically splits content into two categories: ham or spam. Ham is desirable content, and spam is undesirable. Mollom screens all of the incoming content to make sure it is of the ham variety, and then posts it to the website. Mollom uses a history of activity on all sites within its network to help determine whether or not content is spam. Post content and the poster's reputation is taken into consideration. In other words, Mollom is like a human moderator on autopilot.
If Mollom is unsure if content is spam, it will go to a secondary line of defense – the CAPTCHA challenge. The user will be given an audio or visual CAPTCHA challenge that they must complete for the content to go live. This not only prevents unsure content from going live, but it also keeps it from being misdiagnosed and classified as spam. If spam somehow makes its way onto the site, the site can report it to Mollom for future reference and to benefit all of the sites within the network. Mollom is available in Free, Plus, and Premium.
The reCAPTCHA module is rather simple in its form but highly effective. CAPTCHA programs generate simple tests that humans can pass but most computer programs cannot. Distorted text is a common CAPTCHA example that will generate a couple of words on-screen that the user must type for acceptance.
CAPTCHA integration works well in various situations, making it an attractive service for a wide range of sites. It can prevent spam emails and comments, be used to verify submissions in online polls, protect registration on websites, and more. The reCAPTCHA service digitizes actual books and scans their text. The text is difficult for computer programs to decipher as it is placed onto an image. Adding reCAPTCHA to your site adds a solid line of defense against spambots, as it requires human input. Not only can you protect the content that gets posted on your site, but you can also protect your email address. reCAPTCHA will ask a user to solve a CAPTCHA in order to view your email address.
SpamSpan is a Drupal module that helps protect email addresses on your site from being harvested by spambots. It works by obfuscating email addresses using JavaScript. This not only protects your own email address, but also any email addresses belonging to your users that have been posted. The obfuscation of email addresses helps to promote more interaction among visitors, since the worry about email address harvesting is diminished.
SpamSpan is compatible with almost all browsers on the market. If compatibility is an issue, SpamSpan will degrade gracefully. While most email obfuscating services require that JavaScript be enabled on the client side, SpamSpan does not. It will offer a clickable link to the email address if JavaScript is enabled. If JavaScript is disabled or not supported by a browser, the email address will still be visible, but presented as user1 [at] example [dot] com.
While the obfuscation technique used by SpamSpan is not completely foolproof against harvesting, it does help, as many spambots will not attempt to collect email addresses that have been hidden using JavaScript. With that being said, SpamSpan is very concise and easy to implement. Best of all, it is free and available for personal or commercial use.
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