I'm building a website with xhtml, css, jquery, php and mysql. In one of the webpages, I have given the option to the user to vote - there is a like and dislike button on the page, and when the user clicks the LIKE/ DISLIKE button, the counter corresponding to that item is incremented/ decremented in the database correspondingly, and then the net count is displayed beside the LIKE/DISLIKE button for that item.
Something like this:
Net Rating: 21
Like Dislike
Now, I would like to restrict the user entry, so that the user may click on the like/dislike button only once. They should not be allowed to keep clicking the like/dislike button and thus affect the count. I understand that this can be restricted by using user accounts through registration of the user and then probably using the session/cookies to monitor user activity, but then I am looking for a simpler solution which does not use session/cookies/user-registration.
Something like - capture current IP of the user, see if this IP has voted, if yes enable restriction. If this seems to be a good logic, please let me know how to capture the ip and then restrict - using jquery/php/any other technology.
Note- i use wamp (apache server with php)
thanks!