CC2652P: How to avoid PanId configuration and Join a trusted network anyway

Roberto Nucera

Part Number: CC2652P
Other Parts Discussed in Thread: Z-STACK, SYSCONFIG,

Good morning.

I'm scanning without luck the docs of both Z-Stack and Zigbee2Mqtt, which i'm using for my gateway instances.

I would (if possible) to avoid the configuration of panId and channels on my Zigbee devices and coordinators (on Z2M instances), making the devices able to choose between at least 2 coordinators in the area without restrictions.

I successfully reach this goal if i set PanId to 0xFFFF on both sides, so the coordinator randomizes it and the devices do not care. Idem for the Channels, where the coordinators choose the best and devices follows.

I know it may be not the best practice and i loose a couple of seconds in the pairing procedure, but this can save me a LOT of time in configuring the PanId and channels to everyone.

So, the devices scan for any available network on any channel and join it...

How can i make sure that my devices connect to a trusted network of mine?

I tried changing the network key on Z2M instance and restart the coordinator with the new key, but the devices connect successfully anyway even without the new key updated.

Any advice would be really appreciated.

Roberto

over 2 years ago

+1 Ryan Brown1 over 2 years ago

TI__Guru**** 217867 points

Hello Roberto,

Here is a Zigbee Security Features SimpleLink Academy Lab that you might find useful. I don't fully understand the use case as described but it is possible to set the Pan ID to 0xFFFF, Primary Channels to all frequencies, and TC Link Key to a different pre-determined value in SysConfig or with the MT API. Setting a new TCLK should make it more difficult for unwanted devices to join since they will not be able to obtain the network key. Of course the TCLK would have to be aligned on all devices and cannot be certified by the Connectivity Standards Alliance as it breaks the Zigbee Specification (hence would be a proprietary Zigbee network). You may also need to use a timer to constantly re-enable permit joining if you want it on at all times, otherwise the network will be closed for joining after BDBC_MIN_COMMISSIONING_TIME expires.

Regards,
Ryan

0 Roberto Nucera over 2 years ago in reply to Ryan Brown1

Intellectual 265 points

Good morning Ryan.

The hint is for sure the correct one. My use case is just that i need to create a proprietary Zigbee network setting a custom TCLK.

Now, i successfully managed to set a custom TCLK in my zigbee routers and end-devices by sysconfig, but i'm struggling to find where to change it on the ZNP coordinator.

I use Zigbee2Mqtt to handle the ZNP flashed CC2652P coordinator, but the only key that i could modify by the Z2M frontend is the ''network key'', no luck for the Trust Center one.

So i'm searching inside the MT interface APIs docs for the suitable command to set my custom TCLK inside the coordinator, without luck so far.

How can i search for it?

+1 Toby over 2 years ago in reply to Roberto Nucera

TI__Mastermind 35030 points

Hi,

Roberto Nucera said:
Now, i successfully managed to set a custom TCLK in my zigbee routers and end-devices by sysconfig

The ZNP example also has a .syscfg file, where you can configure the TCLK like you've done for routers and end-devices.

To create a custom MT command, you can use the MT_APP_FUNC:

https://e2e.ti.com/support/wireless-connectivity/zigbee-thread-group/zigbee-and-thread/f/zigbee-thread-forum/927794/mt-command

https://dev.ti.com/tirex/content/simplelink_cc13xx_cc26xx_sdk_6_40_00_13/docs/zigbee/Z-Stack%20Monitor%20and%20Test%20API.pdf

Thanks,
Toby

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CC2652P: How to avoid PanId configuration and Join a trusted network anyway