Background: I recently came across a child porn website and by US law I am obliged to report it. I've decided to collect evidence for a formal report; however, I don't want to reveal my identity due to the fear of retaliation.
To collect evidence, I make some new accounts with new browser cookies and new IP address. But the website's admin manually identifies those accounts as smurfs. I am in fear that my identity is still exposed.
Question: besides IP address and some browser cookie, what else is usually collected by a website that can help their admin to identify me?