Forum OpenACS Q&A: Re: How to uniquely identify user's PC without using IP address?

A colleague and I came up with a simple solution using Javascript. It works by including on the login page a JavaScript file stored locally on the PC. The machine name is hard-coded into the script, and the script creates a hidden input in the login form containing that machine name, which is passed to the login program. I then store the machine name as a session property. A call to ad_get_client_property gives the machine name.

Thanks to everyone for their help.