alt Hacker NewsIf your ISP issues an IPv6 address, isn't that pretty much game over for anonymity/uniqueness?
Replies
tke248 • today at 7:14 PM
A VPN or Tor swaps it out entirely, which your browser fingerprint survives. It is a strong identifier, not a permanent one.
Not usually, if you're comparing it to IPv4. Many ISPs give each customer a persistent IPv4 address that doesn't tend to change over time. Because most people use NAT (internal IP address != external IP address), a server you connect to can't identify the specific computer or device.
With IPv6, it's true that in many cases servers will see you as connecting from the specific IPv6 address of your computer/device. However, IPv6 addresses contain many parts, like:
where the left part is basically the equivalent of the unchanging IPv4 address you got from the ISP, and the right part identifies your specific device. But in most OSes the right part is randomly generated and changes on some cadence (e.g. daily).So in many cases, the ability for a server to individually fingerprint your device solely based on the IP address is roughly equivalent between IPv4 and IPv6. (This isn't the case if the ISP does CGNAT on IPv4, where you're sharing your IPv4 address with many customers - this would be similar in magnitude to a VPN in terms of the ability for a server to fingerprint you based on IP.)