Up to Pia version 5.10, the protocol port was used to determine the message type.
In Pia version 5.11 and later, all packets are sent through port 0 and always contain the NatProbeData structure.
The following version numbers are advertised during the connection request:
| Pia version | Version |
|---|
| 5.19 - 5.43 | 0 |
Probe request
Probe reply
Dummy packet
| Offset | Size | Description |
|---|
| 0x0 | 5 | “Dummy” |
NatProbeData
| Offset | Size | Description |
|---|
| 0x0 | 4 | Service variable id |
| 0x4 | 1 | Probe type (0=request 1=reply, 255=dummy) |
| 0x5 | 3 | Padding |
| 0x8 | 8 | System time (OSGetSystemTime on Wii U, nn::os::GetSystemTick on Switch) |
5.11 - 5.43: