Get unique value of a user other than IP
<p>I am developing a PHP application, only used by our employees in 3 diff locations. I want a when, whom, where log.  I am getting only 3 unique IPs, since all of them using internet via proxy and chrome browser mostly. Is there any other unique value other than IP or Browser info? that should be record by javascript or PHP.  I know there is a security problem of getting computername or local ip, but please suggest and anyother solutions.</p>

<p>Waiting for your valuable suggestions</p>
