I don't know of any ISP that will give you a public ipv4 address for free.
More interesting is windows 11 auto configuring ipv6. Does you pc have a public ipv6 address starting with 2:: or fe80:: link local address?
Quick ipv6 crash course. Instead of DHCPv4 (there is DHCPv6 but it's optional) being required for address configuations, ipv6 uses somting called Stateless address Autoconfiguration (SLAAC). Normaly your router sends out Router advertizments packets and this tells devices about the default gateway, public prefix, dns etc... and pc will generate a public ip of (64 bit public prefix):(64 bit random number).
It seems like Windows 10 and eariler will not do ipv6 unless your router advertises it.
TL;DR learning ipv6 is easier than disabling it at this point
>I don't know of any ISP that will give you a public ipv4 address for free.
There probably isn't an ISP that gives out *static* public IPv4 addresses for free, but any ISP that supports IPv4 without CGNAT will give out public IPv4 addresses by definition. The two I've used in the US (Frontier, now Ziply) certainly do.
I suppose "for free" is a relative term, since no ISP I have will give me IP service for free either. However none of the residential ISPs available to me in my section of the US will offer a discount to not give me a public IPv4 address, so I think that counts as getting one "for free"?
More interesting is windows 11 auto configuring ipv6. Does you pc have a public ipv6 address starting with 2:: or fe80:: link local address?
Quick ipv6 crash course. Instead of DHCPv4 (there is DHCPv6 but it's optional) being required for address configuations, ipv6 uses somting called Stateless address Autoconfiguration (SLAAC). Normaly your router sends out Router advertizments packets and this tells devices about the default gateway, public prefix, dns etc... and pc will generate a public ip of (64 bit public prefix):(64 bit random number).
It seems like Windows 10 and eariler will not do ipv6 unless your router advertises it.
TL;DR learning ipv6 is easier than disabling it at this point