A Teredo relay potentially requires much network bandwidth. Also, it must export (advertise) a route toward the Teredo IPv6 prefix (2001::/32) to other IPv6 hosts. That way, the Teredo relay receives traffic from the IPv6 hosts addressed to any Teredo client, and forwards it over UDP/IPv4.

コンピュータネットワークにおいて、Teredo とはIPv6移行技術の一つである。 IPv4を用いてインターネットに接続可能であるが、通信経路のどこかに IPv6 を理解しない通信機器が存在するために IPv6 ネットワークと直接接続ができないホストに対し、完全な IPv6 接続を提供する。 Disable IPv6 Windows 10: 3 Methods to Disable IPv6 in Nov 26, 2019 IPv6 Day - Teredo Servers

IPv6 - Cisco

Sep 02, 2019 5 Methods to Fix Xbox Teredo Is Unable to Qualify in Check Xbox Networking. You should know that the system settings of Windows 10 contain gaming …

RFC 4380 - Teredo: Tunneling IPv6 over UDP through Network

Sep 02, 2019 5 Methods to Fix Xbox Teredo Is Unable to Qualify in Check Xbox Networking. You should know that the system settings of Windows 10 contain gaming … enable teredo, IPv6 - Microsoft Community