First or later any website administrator have to combat this war, especially when your site starts to be a little bit more popular. Tipically the most common spam target at your site are:

Registration Spam

This is one of the most common target of Spam that you might see on a typical Joomla site. I have seen tons of fake accounts  this happening both by automated scripts as well as human

Forum Spam

If you have a forum on your site  you are a target for this kind of Spam. This typically contains ads text and links.

Comments Spam

If you have a comments system to allow users to post comments on articles  you are a target for this kind of Spam. This typically contains ads text and links.

Contact Spam

If you use Contact the email account are a target for kind of Spam

The SpamDog give you some weapon to fight Spam:

Passive weapon

Whenever a content or registration is sumbitted is first evaluated by specialized webservices like:ProjectHoneypot, StopForumSpam, FSpamlist, BotScout, Akismet, Mollom, Defensio, and some RBL

and only after an "ham" classification are allowed.

Active weapon

These webservices databases are updated continuosly so maybe the spammer could be trapped some days later

Here is an example on how the SpamDog  work 


Left blank for test your ip

 This test will check the IP address against several DNS based blacklists. (Commonly called Realtime blacklist, DNSBL or RBL).  If your ip has been blacklisted, some email/comment/registration you send may not be delivered.  Blacklists are a common way of reducing spam.

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