As I recall, this was seen as a concern in the early days so "privacy extensions" were added to the implementation standard for IPv6. Macintosh, Windows, iOS,

As I recall, this was seen as a concern in the early days so "privacy extensions" were added to the implementation standard for IPv6. Macintosh, Windows, iOS, and Android all rotate their auto-configured IPv6 addresses at a regular interval. It used to be a day but I think I've seen it as short as an hour: https://www.internetsociety.org/blog/2014/12/ipv6-privacy-addresses-provide-protection-against-surveillance-and-tracking/ https://www.internetsociety.org/blog/2014/12/ipv6-privacy-ad...