Actually there can be an arbitrary number of addresses per device, thanks to the privacy extensions. Since your “device id” is a simple derivation of your MAC address, technically you could be tracked across ipv6 networks through that.
Therefore most modern oses will create a time limited random address (within the prefix) to use. When the connections using that address have died, the address is retired. New addresses are generated on a periodic basis. So if you have long lived connections you could have several active privacy addresses at the same time.
Therefore most modern oses will create a time limited random address (within the prefix) to use. When the connections using that address have died, the address is retired. New addresses are generated on a periodic basis. So if you have long lived connections you could have several active privacy addresses at the same time.