Unique web browser identification ID for web control panel logins in Perl

Question

Do web browsers have a unique ID that can be passed on to Perl scripts? (Like a unique serial - like products that you buy in the shop have for example)

For instanc

Answer 1

No, browsers don't have a unique ID. There is no such thing. If there were such a thing, it would be an online advertising company's dream!

That said, if you're serving up your site via HTTPS, you can issue your clients with client-side X.509 certificates. These would be cryptographically signed by your organization, so fairly unforgeable. (Though obviously if somebody had access to your client's computer they could make a copy of it - the same would be true of any browser ID number though!) Once the certificate is installed, every time the browser makes an HTTPS request to your website, your website can ask for its certificate, and this can be used to verify the user's identify.