I'm looking for solution to identify unique users. For example: - to prevent same user to vote twice a day, or - to prevent same user to register twice a day Currently, I'm using: - IP address + cookie + storing users data to database However, there are still users with: - dynamic IP address - disabled (or deleted) cookies Are there any other data (like ServerVariables), which can help me to track them down? THNX
I don't think there's much else you can do unless you make your users create and account or log into an account on your web site first, or unless your visitors allow you to install stuff on their PC - very unlikely. Session variables would take care of a user not having cookies enabled, but only for as long as they stayed on your site, didn't restart their browser, or re-visited once the session variable had expired (default 20 minutes). There's only so much information you can capture from a brower and you're limited by what is publically available and what the visitor allows. You could set it up so that if they don't accept cookies they can't do anything but slightly sophisticated users who want to by pass this security will simply delete the cookie anyway. You could create something like an ActiveX control that captured the MAC address of their computer and you could then tie-down the users to an individual computer. The chances of them letting you install that component - zero, except for the insanely unsafe user who shouldnt be taught how to turn a PC on never mind surf the web. Back the the first paragraph - there's not really much else you can do above what you are doing already.