if router has NJ=ff and coordinator NJ=0 are new devices connected to the router seen by the Coordinator?

Question

I am fiddling with pan_id=0 for a HA devices and was just wondering. It seems like a good practice to not use FF (always allow joining) so you don't grab HA devices that are not yours

Answer 1

Any node that is on the network can be seen by any other node within the network.

You can set the NJ to any value between 0 - 0xFF. When less than FF, it allows joining for a period of time.

You can also enable or leave joining at FF and then change it to 0 once all of the desired devices have joining. You can also use the NJ value to control who an end device joins with. By setting NJ to 0 one say the Coordinator and leaving NJ to a value other than 0, I can allow an end device to join the router. Yet as it is on the network then, any other node within the network can still access it.

Comments

thanks, I have also run some tests.  And it does look as I will need to "turn on and off" node join time (NJ) when ever adding HA devices. I'm just worried as HA becomes more popular HA devices may join with the wrong network if they both have a NJ on with any of the routers or Coordinators.