RE: Bluetooth Mesh vs Thread in low power sensor network

Hung Bui — Thu, 15 Nov 2018 09:49:00 GMT

Hi Mateusz,

1. It will be a full LPN example and a precompiled Friend node.

2. It's theoriticaly possible to change PHY to run Mesh however for now it's not covered in the spec and you won't be able to qualify your product. So testing is ok , production not yet.

RE: Bluetooth Mesh vs Thread in low power sensor network

Mateusz Gancarczyk — Thu, 15 Nov 2018 07:04:59 GMT

Thanks for great answer!

Two more question:

1. In the next SDK will be full example of LPN and friendship device?
2. Can I run Bluetooth Mesh with Bluettoth 5.0 Long Range ( x8 ) mode?

RE: Bluetooth Mesh vs Thread in low power sensor network

Hung Bui — Tue, 13 Nov 2018 14:49:39 GMT

Hi Mateusz,

1. When friend node fails, the LPN by not able to talk to its friend will start looking for new friendship. What would be lost here would be the messages for the LPN that the friend node cached.

If the Low Power node does not receive a response within the ReceiveWindow, it should resend the Friend Poll message. It is recommended to resend this message 3 times, which assures a good balance between reliability and power consumption.
If no response has been received to multiple Friend Poll messages before the PollTimeout timer expires, the friendship is terminated. The Low Power node may repeat the Low Power establishment operation.

(Section 3.6.6.4.2 in Mesh Spec v1.0)

2. It's coming in the next SDK, at least the LPN . Should be available by the end of this month.

3. Yes it can find a new parents, but same as Friendship termination, the cached messages may be lost.

4. It's hard to say pretty much depends on the operation of your network. It's more about which technology fit more into your application. Mesh is a flooding mesh when Thread is a routed mesh. Thread has IPv6 to each nodes.

5. In thread the router does the provisioning to join a node to the network. Each network has a leader to provision the routers.

Regarding the low power option, there are many alternative to achieve low power besides the Low Power Node and Friendship solution.

- You can just put a normal node to sleep, it may miss packets send to it, but if it's simply a temperature sensor for example, we just need to receive data from it.

- Or you can make your device to advertise normal BLE advertising packet, and define a protocol in your normal mesh node to forward those packet into mesh, this is what we have in the Enocean energy harvesting light switch example.

- Another option is to configure your device as a GATT client proxy, to connect to a Proxy. This way you just need to maintain a normal BLE connection.