| IPv4 Client | IPv4 Operator AF | IPv4 Server AF | Direct communication is supported. |
| IPv4 Client | IPv6 Operator AF | IPv4 Server AF | This is a 464 use case. The ION encodes the IPv4 address using the Well Known Prefix (64:ff9b::/96). The NAT box strips the prefix and forwards the IPv4 packet. |
| IPv4 Client | IPv4 Operator AF | IPv6 Server AF | Transparent to the ION device; the operator is responsible for an IPv4 equivalent address for the IPv6 server. |
| IPv4 Client | IPv6 Operator AF | IPv6 Server AF | The ION employs the Well Known Prefix (64:ff9b::/96) for IPv4 address encoding. The ION converts the IPv4 destination to an IPv6 encoded IP for routing. |
| IPv6 Client | IPv4 Operator AF | IPv4 Server AF | DNS64 is utilized. When the operator provides DNS64, it responds with an IPv6 address containing the 64:ff9b::/96 prefix. The ION strips the prefix and sends the IPv4 packet. |
| IPv6 Client | IPv6 Operator AF | IPv4 Server AF | This scenario is transparent to ION; the operator needs an IPv4-mapped IPv6 address. |
| IPv6 Client | IPv4 Operator AF | IPv6 Server AF | Packets are dropped. |
| IPv6 Client | IPv6 Operator AF | IPv6 Server AF | NAT66 is supported using 6wind. |
| Dual-stack Client | IPv4 Operator AF | IPv4 Server AF | The client uses its IPv4 address for the connection. |
| Dual-stack Client | IPv6 Operator AF | IPv6 Server AF | The client uses its IPv6 address for the connection. |
| IPv4 Client | IPv6 Operator AF | Dual-stack Server AF | The ION uses the Well Known Prefix (64:ff9b::/96) for IPv4 address encoding. The system handles DNS and address mapping to send packets to the dual-stack server. |
| IPv6 Client | IPv4 Operator AF | Dual-stack Server AF | This requires DNS interception and will be supported in releases beyond 6.4.2. The system maps the IPv6 AAAA record to an IPv4 A record for the client. |
