The following operating systems use IPv6 privacy extensions by default:
All versions of Windows after Windows XP
All versions of Mac OS X from 10.7 onward
All versions of iOS since iOS 4.3
All versions of Android since 4.0 (ICS)
Some versions of Linux (and for others it can be easily configured)
Sure you could track such IPs by looking at routing paths/the subnet prefix but that's not different than IPv4. If you posit that a dynamic IPv4 is completely random you might be surprised, it's just drawn from a small pool that at some point has to be routed for packets to reach it, and even then it's not updated that frequently (usually on router reboot). Comparatively, privacy IPv6 addresses get rotated very frequently (can't recall but could very well be 15min)
You can have multiple IPs per interface, e.g typically:
https://datatracker.ietf.org/doc/html/rfc4941The following operating systems use IPv6 privacy extensions by default:
Sure you could track such IPs by looking at routing paths/the subnet prefix but that's not different than IPv4. If you posit that a dynamic IPv4 is completely random you might be surprised, it's just drawn from a small pool that at some point has to be routed for packets to reach it, and even then it's not updated that frequently (usually on router reboot). Comparatively, privacy IPv6 addresses get rotated very frequently (can't recall but could very well be 15min)