LSOs deleted in latest browsers

Local Shared Object, sometimes referred to as SuperCookies, or Flash Cookies is used by my website to uniquely identify user's computer and prevent him/her from using same credentials on many computers. Up until very recently web browsers were unable to delete data in LSO which made it a good tool to serve my purpose. IE9, Firefox 5 and Safari now dump the LSO data when user chooses to delete the cookies/clear history. I understand the reasoning behind this, but in my case I am not secretly tracking user's data or collecting information about the user in order to exploit the personal data.

Is there a way to add my site to some sort of "LSO trusted zone" in the major browsers so they would not delete data stored in LSO by my website?

If there is, I could instruct my users to set their browser preferences accordingly. If not, I would probably have to come up with a different way to positively identi开发者_运维百科fy user's computer from a web application (maybe browser fingerprinting?). I saw some banks doing this, and when one tries to log in from a new computer a screen is displayed that "it is the first time you are using this computer to log in". I wonder how that is done, definitely not through IP, since people using the same router will have same IP (large corporations, business/home networks, library)

No, there's no way to do that. If you found one, you could find yourself subject to a class-action lawsuit.

when one tries to log in from a new computer a screen is displayed that "it is the first time you are using this computer to log in".

They're generally using LSOs for this. For those of us who routinely clear cache for test purposes, we see this message on every login.