There is an interesting discussion about spam and OpenID going on at Matt Mullenweg's blog. The discussion was triggered by the policy decision of social bookmarking site Magnolia to restrict signups to OpenID users. According to the site, 75% of new accounts were being created at Magnolia by spammers using automated tools (our friends the 'spambots'). They say that by restricting access to OpenID users, the rate of spam-account creation decreased. In the discussion, there is a lot of talk about whether OpenID should be used to fight spam, and whether it could be an effective spam-fighting tool in the long term.
Here are my thoughts. Spammers can create OpenIDs too, and a single sign-on system might be many a spammer's wet dream. It gives them easy access to millions of sites in one fell swoop.
Now, OpenID by itself can't prevent spam. All it does is provide a globally unique identifier for any given user on the planet. This is where a tool like Mollom comes in. At Mollom we're already maintaining an internal reputation for each OpenID account we encounter while assessing submitted content. Combine an identity system (OpenID) with a reputation system (Mollom) and it becomes a lot easier to separate spam users from non-spam users. Simon Willison said it best: "a trust system requires identity first". A globally unique identifier combined with reputation tools give us a powerful weapon to fight website spam. OpenID's attribute exchange might become Mollom's best friend ...
Similarly, Tim Berners-Lee is experimenting with combining FOAF ("friend of a friend") and OpenID to fight spam: you can only comment on Tim's blog if you are no more than a certain number of degrees of friendship away from him. Of course, it is a widely accepted theory that we are only six degrees away from everyone in the world so I do wonder how effective this would really be in the long run.
It is still early days in these debates and experiments, but for now, Mollom can already protect your login and submission forms with an image or audio CAPTCHA.
Either way, it is an interesting discussion that makes you wonder. Where will OpenID be in 3 years? Where do you think the website spam problem will be in 3 years? How will this affect online communities?
I have my own thoughts and predictions and it was one of the principal reasons for co-founding Mollom ...
— Dries Buytaert