I'm building a small application that highly depends on anonymous user voting on some sort of items. It's so small that requiring registration would be tedious and could not be justified.
Anyway, I did some research on this, including a search here on stackoverflow (https://stackoverflow.com/search?q=anonymous+votes), and doesn't seem that there's a satisfying answer.
My question is: are there any security measures that I can apply to prevent gaming anonymous votes?
One thing comes to mind is CAPTCHA, but I'd like to avoid that since users will vote on multiple items in a very short period of time, and CAPTCHAs will just annoy them.
Another thing I thought of is limiting the number of votes per minutes from a single IP (in addition to a cookie), but not sure how this is going to work.
Any thoughts?
You can use the CAPTCHA once to both confirm the vote and create a session with the IP and cookie.