Hello,
I have one voting website, but very simple, so some one can vote and vote again, and stil count.
Maybe some one know how to protect this feature so one visitor could make voting just for 5 at one time, and will automatic disable after 5 vote up until the next 30 minutes.

I'm really need this code.

Thank you very much
edwin

There are 2 ways that I can think of off the top of my head to do this. One way is to use cookies to remember that a user has already voted. However, users can easily overcome this by simply deleting their cookies and re-voting. This will, however, prevent them from spamming submit a thousand times.

The second way (and more complicated) is to get a user's IP address when they submit their vote. You can store their IP address in a database and if they try to vote again, simply remind them that they have already voted.

You can find information about cookies all over the internet and the same for retrieving and storing IP addresses.

thank you very much, I will try to search internet. Will come back again after searching.

By IP won't be as helpful as you might think -- some large companies change the IP from page call-to-page call. Requiring users to be logged in is the best protection you can have for not allowing repeat voting.

Sorry, I'm really newbie.
How I can setup to be logged between models and voters?
I think this idea really genious, to give them form to fill out with their name, address and email when upload photos and vote.
I can send you upload.php file to be more clear? Or you can give me simple instruction about this?

Please help me with more detail, I'm really needed this information
Sorry for my broken english.

Why not simply ask whoever developed the site code?

They are the ones who would know HOW to integrate any such mechanism.

Ohh...thanks for the information.
Would you tell me where I can hire someone with this project?
many thanks.

http://www.webmaster-talk.com/marketplace

Working solution based on cookies is to accept the vote only if *proper cookie* is set and ignoring the vote in all other cases. Though such an approach will ignore something like 1% visitors which are too paranoid.

I've been working on a simple voting system so I solved this problem with checking IP and using time period for the same IP. Because there are many visitors using the same IP(depends on ISP) so just blocking IP is not a great solution.

Thanks for you all.
Until now I don't know what the best to make like this, also how I can setup my site to protect from spam voters.