What is the canonical way a mesh sensor device communicates state

[James]

I've played with the Generic OnOff Model Server in a mesh network.
It seems like the way state of whether the device is on or off is communicated is through an access message with opcode corresponding to OnOff Status (0x82 0x04).

i.e a 3 byte bluetooth mesh access message of 0x82 0x04 0x01 would mean the device is on,  0x82 0x04 0x00 would mean the device is off. 

I'm interested in setting up the right/canonical way for a device to communicate presence detection to a mesh network. 
From the below link [1] I see that there is a "Presence Detected" mesh property that is predefined. 

[1] https://www.bluetooth.com/specifications/mesh-specifications/mesh-properties/

1. How would a device communicate it's presence property to participants in a mesh network? 
2. Is there a standard (interoperable) way of doing this? (And is it documented somewhere?)
    - Is it through access messages with a specific opcode? 
    - If it is, what does the parameter format look like?
    - Is the device supposed to expose it through a GATT characteristic or Service Data? 

[Hung Bui]

Hi James, 

The "presence detection" you mentioned is used for detecting if there is a person inside a room for example.

Is it that what you want to do ? Or you want to detect the presence of the mesh node ? that it's active in the mesh network ? 

If it's the latter, you should use the "heart beat" for the purpose. You can read more about heartbeat at section 3.6.7 in the Mesh profile specification v1.1 

[James]

Hi Hung Bui,

I am indeed interested in communicating that there is a person inside a room. 
Obviously if I define my own model and opcode and parameters I can have something working for myself, but I was wondering if there was a spec for that already. That is, what opcodes to use and what the parameters look like, similar to the Generic OnOff Model. 

James

[Hung Bui]

Hi James, 

The presence detection property is to be used inside a Sensor Status message (see section 4.2.14, Mes Model Specification v1.1) 

The format is defined in the section.  The property ID is in the XML link that you pointed to. 

Sensor Status has opcode 0x52.