Difference between link-local and global link addresses in ISATAP

Any IPv6 adapter should always have two IP addresses if you're using it for internet traffic - your link-local address and your global address.

Your global address is world-routable, so anyone anywhere in the world can see that IP address (although of course, there should be a firewall between you and them to stop them from actually accessing you).

Your link-local address is just for your local area network. Consider it the equivalent of a 192.168.0.1 or 10.1.1.1 address. They are not routable, and can be used for internal communications, so that if your world-routable prefix changes, you don't have to update all your IP references to internal IP addresses.

The only functional difference is that your link-local address is not routable, and your global address must be routable. There are issues where non-routable global addresses have been allocated (via DHCPv6) for whatever reason, your computer THINKS it has a routable IPv6 address when it doesn't, and then all your IPv6 connectivity breaks.

_{I also notice that your global IP address has been assigned manually with a dot-decimal address, which makes me wonder if your IPv6 network is configured correctly as it's obviously not using auto-config with RA announcements)}