session - What is a reliable method to record votes from anonymous users, without allowing duplicates -

First of all, I searched as the best and read all the questions that were appropriate, but nothing special It was not answered from This is not a duplicate, not a fixture.

Obviously, if anonymity is allowed on a website, then there is no idiot to stop a person from voting more than once.

However, I am thinking that with the experience someone can help me in tracking a completely unique visitor and coming in a reliable manner to vote against those credentials.

Currently, I am ensuring that only one vote per item / session combo, it has been easily affected by restarting the browser, changing browsers / computer, or clearing your session data. goes.

The recording against the IP seems to be the next reasonable solution but I am surprised that it will be very false positive (Many people

whether there is a middle ground or some other method / combination What I see?

I would rather take more data about the session without asking the question All (directly with browser, OS, installed plugins, version numbers, IP addresses etc.) and this hash.

Record hash and raise a counter If you want multiple votes allowed, please include a timestamp (daily, hourly etc.) in salt to make the time for malls sensitive, make 5 votes per day.