| Component | Role | Example | | :--- | :--- | :--- | | | The host behind the NAT seeking IPv6 connectivity. | Windows PC, Xbox One. | | Teredo Server | A well-known, globally reachable IPv4 host. Helps the client determine its external IPv4 address and UDP port (NAT mapping). | teredo.remlab.net | | Teredo Relay | A router that forwards IPv6 packets between the Teredo network and the native IPv6 internet. | ISP-operated or public relays. | | Teredo Host-Specific Relay | An optimization where a native IPv6 host acts as a relay for a single Teredo client. | Not common today. | 3.1 The Teredo IPv6 Address Format A Teredo client generates a routable IPv6 address ( 2001:0::/32 prefix) with embedded information:
With the accelerating global adoption of native IPv6 and superior translation mechanisms like NAT64, Teredo has reached end-of-life. It remains a footnote in networking history—a bridge that served its purpose but is now being dismantled. Organizations and users should actively disable Teredo unless a specific, non-replaceable dependency (like older Xbox gaming) exists. // Check Teredo status netsh interface teredo show state // Enable Teredo (client mode) netsh interface teredo set state client teredo protocol
// Set specific Teredo server netsh interface teredo set state server=teredo.remlab.net | Component | Role | Example | |