1. Tunnel IngressTunnel Egress IPv4 Network 192.0.2.1192.0.2.2 Src: 192.0.2.1 Dst: 192.0.2.2 Proto: 41 IPv4 Header V6 Header

2. 20 02 c0 00 02 01 IPv4 address 6to4 IPv6 /48 prefix 192. 0. 2. 1 163248

3. IPv4 Network 6to4 Site 6to4 tunnels

4. 2001 0000 c000 0201 48a3 ec77 5edc IPv4 Teredo Server address Teredo /128 address 192. 0. 2. 1 1632 64 IPv4 Teredo Client NAT Flagxntl UDP Portxtnl IPv4 address 10. 1. 2. 3 80 96 5000 1 (Cone) XOR ffff XOR ffff random padding

5. Teredo Client IPv4 Network IPv6 Network Restricted NAT TEREDO SERVER TEREDO RELAY IPv6 host 1 2 3 4 5 6 7 8 9 1. Teredo ICMPv6 Echo Request from Teredo Client to Server 2. Forwarded IMCPv6 Echo Request from Server to Host 3. IMCPv6 Echo Reply from Host to Relay 4. Teredo bubble from Relay to Server 5. Teredo bubble from Server to Client 6. Teredo bubble from Client to Relay 7. Forwarded Teredo ICMPv6 Echo Reply from Relay to Client 8. Initial packet Teredo-tunnelled from Client to Relay 9. Forwarded initial packet from Relay to host