Changing default TC link key in ZBOSS

RE: Changing default TC link key in ZBOSS

mmmark84 — Mon, 13 Sep 2021 06:59:05 GMT

Thank you for your answer. I think we are going to change the way we use our installations, based on this information.

RE: Changing default TC link key in ZBOSS

Marjeris Romero — Fri, 10 Sep 2021 10:53:06 GMT

Hi again,

To summarize my previous answers:

For centralized networks ZBOSS uses global link key defined with ZB_STANDARD_TC_KEY, set by default to ZigbeeAlliance09. There is no API to configure this, it will require the ZBOSS libraries to be recompiled.

An unique link key can be generate in a similar way when using install codes, but indeed this seems to be a Zigbee 3.0 feature.

For distributed networks you can set a custom distributed link key by calling zb_zdo_set_tc_standard_distributed_key().

These are the only 3 types of link keys we support with the ZBOSS stack. I think this is in accordance to the Zigbee Base Behaviour Specification (section 6.3 Link Keys).

RE: Changing default TC link key in ZBOSS

mmmark84 — Wed, 01 Sep 2021 05:40:04 GMT

We use TC for random network keys and use a pre-configured unique link key for every installation (coordinator/end device combi)

I have read the part about the install codes, but that is a zigbee 3.0 spec option. The xbee's we have installed, can not use zigbee 3.0 as far as I know (only the newer xbee 3 devices can).

RE: Changing default TC link key in ZBOSS

Marjeris Romero — Tue, 31 Aug 2021 14:09:49 GMT

Hi Mark,

Do you know if the Xbee devices form a centralized or a distributed network?

For distributed networks we have the following API function zb_zdo_set_tc_standard_distributed_key() to set a custom distributed key.

For centralized network is my understanding that the TC is responsable for establishing a random network key for each device as they join, using the default global link key or from a pre-configured unique link key derived from "install code".

We have support for using "install code" for deriving a pre-configured TC link ke using the install code API.

Take a look at the 'Security' section in the Zigbee stack API overview in the infocenter.

These are the methods supported in our stack.

RE: Changing default TC link key in ZBOSS

mmmark84 — Mon, 30 Aug 2021 05:40:41 GMT

The default link key yes, that shall be ZigBeeAlliance09. It also is allowed (zigbee spec) to use a pre-configured unique link key, that is known by the trust centre and joining node.

I am trying to use a preconfigured key instead of the defined ZigBeeAlliance09 default key for joining.

It seems to me that bit is not supported at the moment?

RE: Changing default TC link key in ZBOSS

Marjeris Romero — Fri, 27 Aug 2021 14:06:52 GMT

Hi,

I don't have experience with Xbee modules but from the Zigbee specification: "The default value for the centralized security global trust center link key shall have a value of 5A 69 67 42 9923 65 65 41 6C 6C 69 61 6E 63 65 30 39 (ZigBeeAlliance09)."

The define ZB_STANDARD_TC_KEY in zb_config_common.h is a pre-compiled parameter and is set to this value based on the Zigbee specification, it's not possible to change.

Best regards,

Marjeris