I've just implemented a provider model for the CAPTCHA used in the Blog Comment Form and Email Contact form. I'm sure you are all familiar with the use and purpose of CAPTCHAs in reducing comment spam. As spammers get ever more sophisticated we seem to need ever stronger measures to defend against their spam. So I figured by implementing the provider model it will be easier for new CAPTCHAs to be used in mojoPortal over time as they become needed or available. You can select which CAPTCHA to use in Site Settings.

Currently I have implemented 3 providers.

The Simple Math Captcha:

The Subkismet Captcha:

and finally

reCAPTCHA, from Carnegie Mellon

The idea of reCAPTCHA is to use the human effort in solving the CAPTCHA to help improve the quality of books scanned with optical character recognition by finding and fixing the mistakes. To use reCAPTCHA you need to get an account and set the private and public keys in mojoPortal Site Settings.

As you can see I've updated this site to the latest code from svn and using reCAPTCHA for this blog.

For reCAPTCHA I used the Controls by Adrian Godong and Joseph Hill from here:

http://recaptcha.googlecode.com/svn/trunk/recaptcha-plugins/dotnet

I'll leave it to someone else if they want to implement a provider for HotCaptcha ;-)