IT notes

ipv6 tunnelbroker

6in4 6in4 uses tunneling to encapsulate IPv6 traffic over explicitly-configured IPv4 links. The 6in4 traffic is sent over the IPv4 Internet inside IPv4 packets whose IP headers have the IP protocol number set to 41. https://en.wikipedia.org/wiki/6in4 “6to4” is a tunneling method that is only interesting for reaching IPv6-only services. And 6to4 makes sense only if one has a public IPv4 address. As a rule, you only need to enable “6to4” if you want to access services that are only IPv6.