I'm rethinking my vision / use of the Mys protocol

as I have chosen a Usb gateway and mostly a communication bus in rs485 (RF is for specific cases)

MyC <---usb---> Gateway Mega2560/Gui-Oled <----RS485---> Nodes1 2 3 <---- RF ---> NodeX

• the controller in a closet
• the gateway on the desk (usb 3 meters)
• the nodes everywhere in the house (in the technical parts)

and as the "real" Node to Node doesn't work (yes a gateway is mandatory for routing)

I'll see how I'm going to do a state management.
I'm testing a feedback on the OLED display of the gateway.

an example of the sketch on the gateway of a remote node

//------ node 36 Link distant ------ 
    const byte LINKY_NODE_ID  = 36 ;  // node linky
    const byte CHILD_ID_PAPP  = 1 ;   // ID papp
    uint16_t valPAPP ;  //  variable valeur PAPP 
    
    //-------- linky papp ------------------
 if (message.sender == LINKY_NODE_ID && message.sensor==CHILD_ID_PAPP  && message.type == V_VA  ) {    // val PAPP
    valPAPP = message.getInt();
    Serial.print("val PAPP. : ");
    Serial.println(valPAPP);                     
    }
      
    //------------ OLED valeur PAPP --------------------------
 void valPaPP()
  {
  oled.set2X();           
  oled.setCursor(37,2);
  oled.print(valPAPP);
  oled.print("va  ");
  }

Gw and stick to the controller, it does not do much, it relays, it is an intermediary.
Couldn't we use the Gateway-Usb to monitor the nodes ?
of their values ? of their states ?

It is possible to fetch node/sensor values. But it is ok when you have few nodes. If your node network grows, this eats lots of your RF bandwidth. IMO, it is unnecessary to poll the values. We have a push mechanism (node sends data to MyC) and in this situation, It is not a good idea to implement pull mechanism as well (MyC asks data from from each node).

"Node down status maintained by MyC" ... yes that's a very good thing.

ideas out loud about the structure of the system:
MyC <--- Gw <--- node1 <---- node2 <--- ...etc
. the nodes give us the values of the sensors
. MyC displays or sends commands and other things

• Gw and stick to the controller, it does not do much, it relays, it is an intermediary.
  Couldn't we use the Gateway-Usb to monitor the nodes ?
  of their values ? of their states ?

The node down status maintained by MyC. If there is no data/heartbeat received from a node for a specified time. MyC assumes that the node is down and marked as down.

another example : I have a node stopped with temperature probes.

Theoretically when I restart MyC the values displayed in the list of Fields, the sensors should be at zero.
But no, they keep their last value.

why MyC will not read the values on the bus
(MyC ---> Gw ---> Nodes)

it's complicated for the values to go to zero (or other sign/value) when the system is restarted or after a last of time passed ???

thanks