Device-to-Device Service¶
The simplest service is a connection between two devices. There is no network layer, so the connection is only used for APDUs. The NPCI provides priority, but other fields such as the DNET/DLEN/DADR and SNET/SLEN/SADR are absent.
After authentication, if the server does not provide the Device-to-Device Service then it will send a Service Request Result with the error code NO_DEVICE_TO_DEVICE_SERVICE.
Protocol Data Units¶
There is only one kind of packet between the client and server, and once the session is established, the two end points are peers.
Device-to-Device Request¶
This packet is sent by client or the server to its peer.
| Field | Size | Description |
|---|---|---|
| BSLV Type | 1-octet | Streaming BACnet (value = X‘82’) |
| BSLV Function | 1-octet | Device-to-Device Request (value = X‘05’) |
| BSLV Length | 2-octets | Length |
| Payload | variable | Application PDU |