Pia Protocols > Mesh Protocol

Protocol Port	Description
0	Unreliable
1	Reliable

Message Type	Description
0x01	Join request
0x02	Join response
0x04	Leave request
0x08	Leave response
0x10	Destroy mesh
0x11	Destroy response
0x20	Update mesh
0x21	Kickout notice
0x22	Dummy message
0x23	Dummy ack
0x24	Connection failure notice
0x40	Greeting
0x41	Migration finish
0x42	Greeting response
0x44	Migration start
0x48	Migration response
0x49	Multi migration start
0x4A	Multi migration rank decision
0x80	Connection report
0x81	Relay route directions

The following version numbers are advertised during the connection request:

Pia version	Version
5.19 - 5.20	0
5.21 - 5.27	1
5.28 - 5.29	2
5.30 - 5.43	3

Join request

Up to 5.10:

Type	Description
Uint8	Message type (1)
Uint8	Station index
Uint16	Padding (always 0)
StationAddress	Station address
Uint32	Ack id

5.11 - 5.18:

Type	Description
Uint8	Message type (1)
Uint8	Station index
Uint32	Ack id

Join response (success)

If the join response is too big to be sent in a single packet it is split into fragments.

Up to 3.10:

Type	Description
Uint8	Message type (2)
Uint8	Number of stations in mesh, including joining station
Uint8	Index of host station
Uint8	Index of joining station
Uint8	Number of fragments
Uint8	Fragment index
Uint8	Number of station info entries in current fragment (N)
Uint8	Base index of station info in current fragment
StationInfo (xN)	Station info list
Uint32	Ack id

4.8 - 4.10:

Type	Description
Uint8	Message type (2)
Uint8	Number of stations in mesh, including joining station
Uint8	Index of host station
Uint8	Index of joining station
Uint8	Number of fragments
Uint8	Fragment index
Uint8	Number of station info entries in current fragment (N)
Uint8	Base index of station info in current fragment
Uint8	Maximum number of stations in first mesh
Uint8	Maximum number of stations in second mesh
Uint16	Padding
StationInfo (xN)	Station info list
Uint32	Ack id

5.18

Type	Description
Uint8	Message type (2)
Uint8	Number of stations in mesh, including joining station
Uint8	Index of host station
Uint8	Index of joining station
Uint8	Number of fragments
Uint8	Fragment index
Uint8	Number of station info entries in current fragment (N)
Uint8	Base index of station info entries in current fragment
Uint8	Maximum number of stations in first mesh
Uint8	Maximum number of stations in second mesh
Uint8	Maximum number of stations (total)
Uint8	Padding
Uint32	Update counter (incremented on each mesh update)
StationInfo (xN)	Station info list
Uint32	Ack id

Join response (denying)

Offset	Size	Description
0x0	1	Message type (2)
0x1	1	Always 0
0x2	1	Always 0xFF
0x3	1	Always 0xFF
0x4	1	Reason

Leave request

Offset	Size	Description
0x0	1	Message type
0x1	1	Station index
0x2	2	Padding
0x4	8	StationAddress

Leave response

Offset	Size	Description
0x0	1	Message type
0x1	1	Station index
0x2	2	Padding
0x4	8	StationAddress

Destroy request

Offset	Size	Description
0x0	1	Message type
0x1	1	Station index
0x2	2	Padding
0x4	8	StationAddress

Destroy response

Offset	Size	Description
0x0	1	Message type
0x1	1	Station index

Update mesh

Because this message is sent through the reliable mesh protocol it does not need to be split into fragments like the join response.

Offset	Size	Description
0x0	1	Message type
0x1	1	Number of stations
0x2	1	Host index
0x3	1	Always 0
0x4	4	Update counter (incremented on each mesh update)
0x8	1	Number of fragments
0x9	1	Fragment index
0xA	1	Number of station info entries in current fragment
0xB	1	Base index of station info entries in current fragment
0xC		StationInfo entries

StationInfo

Up to 5.9:

Type	Description
StationConnectionInfo	Connection info
Uint8	Station index
	Padding such that the size becomes a multiple of 4 bytes.

5.10 - 5.18:

Offset	Size	Description
0x0	0x3E	StationLocation. If it takes up less than 0x3E bytes the remaining bytes are filled with 0's.
0x3E	1	Station index
0x3F	1	Padding