Mesh protocol!

RE: Mesh protocol!

d21d3q — Thu, 07 Jan 2016 12:18:07 GMT

Bluetooth 4.3 might have mesh implemented

RE: Mesh protocol!

David Edwin — Thu, 29 Oct 2015 08:23:21 GMT

Please use the blog post on devzone.nordicsemi.com/.../ to get a better understanding on how to get it to work. You need to use the _gatt hex files to enable mesh and GATT.

RE: Mesh protocol!

Jacksonlv — Thu, 29 Oct 2015 02:59:19 GMT

I followed the guide of github.com/NordicSemiconducto... to try the mesh with NRF51822.But there seem no discribtion about which softdevice we should use.I loaded the s110_nrf51822_7.3.0_softdevice.hex and rbc_mesh_led_example.hex to the nrf51822. I add code to let the led blink as 1s on 1s off.

while (true)
{
    sd_app_evt_wait();
			led_config(1, 0);
			led_config(2, 0);
			nrf_delay_ms(1000);
			led_config(1, 1);
			led_config(2, 1);
			nrf_delay_ms(1000);
}

And the led will blink but I can't find the Mesh GATT service using the "lightblue" APPs.

RE: Mesh protocol!

David Edwin — Thu, 18 Dec 2014 12:11:46 GMT

There is a sample mesh protocol available on the nRF51 at https://github.com/NordicSemiconductor/nRF51-ble-bcast-mesh .

RE: Mesh protocol!

David Edwin — Thu, 18 Dec 2014 12:10:40 GMT

There is a sample mesh protocol available on the nRF51 at https://github.com/NordicSemiconductor/nRF51-ble-bcast-mesh , this can be used to enhance your understanding of the mesh with BTLE. Feel free to contribute and comment.

RE: Mesh protocol!

Marty — Wed, 24 Sep 2014 18:40:06 GMT

Almost a year later, is there still no plan for a BLE mesh solution? This has become a hot topic in the IoT world.

RE: Mesh protocol!

Paul — Wed, 26 Feb 2014 17:13:52 GMT

Hi Ling

I am working on a project requiring a small scale of mesh on top of ANT+. Number of nodes is limited to 64 right now. Most of the nodes are stationary, but self-forming and self-healing is still required but seconds of time delay for these to happen is OK.

May not be a whole year, but I will definitely call 8 months is lucky!

RE: Mesh protocol!

Ling LI — Fri, 25 Oct 2013 14:59:15 GMT

@Hung: Thanks for the detailed explaination. I browsed the pdf you linked above and noticed it actually refers ANT's mesh as "static mesh" and "practical mesh".

I came to BLE from ZigBee, so I tend to equate mesh with self-forming, self-healing network with AODV style routing. My mistake :) .

RE: Mesh protocol!

Hung Bui — Fri, 25 Oct 2013 14:23:42 GMT

@Ling: You are right. I wasn't very correct to say that ANT protocol support mesh network directly, however it's pretty straight forward to implement an ANT node to relay data, which is necessary to create a "practical" mesh network.

For instance node A can setup a broadcast channel, node B can setup a receive channel and a broadcast channel, and node C can setup a receive channel. The synchronization, power management and pairing between A and B, B and C is fully handled by ANT.

However the application in each node will need to setup individual channels, and specifically node B will need to take the receive channel data from node A and write the data to its broadcast channel (this is very easy to do). Data on a broadcast channel can then be received by anyone on the same network.

The challenge here will be to inform node B that it should start to look for node A, if node C cannot receive data from node A directly.

However this might not be very difficult. For instance node C can by default be setup to try to receive data from node A, if no data is received within reasonable time node C can instead setup a broadcast channel to request anyone nearby to try to search for node A.

This can then be received by node B that by default has a receive channel open, then node B will setup a second receive channel to search for node A, once node B acquire node A, it can inform node C that it has found node A by sending data on the reverse channel back to node C. Since all channels are bidirectional this is straight forward.

Each node can setup up to 8 ANT channels, which can be a combination of receiver and broadcaster channels.

Unfortunately, at this moment, we don't have an example or app note for the implementation.

RE: Mesh protocol!

Ling LI — Fri, 25 Oct 2013 02:18:23 GMT

@Hung -- Interesting. Isn't ANT mostly a star topology consisting of HUB and SENSOR? Sure the hubs can be linked together to form a tree or mesh, but I don't know if routing protocols are available. If not, it means application still has to take care of the inter-hub communication. Could you give more information on this?

RE: Mesh protocol!

Hung Bui — Thu, 24 Oct 2013 12:19:36 GMT

@Jørgen: You can have a look at ANT protocol which does support Mesh topology. The protocol specification is provided here.

We have several product that support ANT such as the nRF24AP or nRF51422 and especially the nRF51922 that support both ANT and BLE concurrently.

RE: Mesh protocol!

Ling LI — Thu, 24 Oct 2013 07:49:32 GMT

Bluetooth 5.0 might support meshing... who knows?;)

But this is highly unlikely. The initial establishment of a mesh can take upto a few seconds before all wireless nodes have discovered their neighbors, and first data transfers will take additional penalty of initial route discovery. This is very much against the purpose of a mobile, ad-hoc networking technology which Bluetooth is known as.

Nordic may want to expand into new application spaces, i.e. wireless sensor and control network. I think their ultra-low-power radio when combined with energy harvesting will be appreciated in many applications. Right now, Bluetooth is the mass market, and BLE is the largest jewel on the crown. So I won't hold my breath.

RE: Mesh protocol!

Jörgen — Thu, 24 Oct 2013 06:26:05 GMT

It would be nice if nordic add support for it to make there products even more attractive.

RE: Mesh protocol!

Ling LI — Wed, 23 Oct 2013 23:23:08 GMT

Given BLE's asymmetric roles and S110's limitation, it's very difficult to do multi-hop on top of it.

If you want to use the nRF51 chip with some other symmetrical, non multi-hop protocol stack, yes, it's possible to do some data forwarding in the application. Don't underestimate the difficulty of a full mesh routing solution; you can waste a whole year on it. Tree routing is better if your application can tolerate higher latency. It's much simpler. The one used in ZigBee 2006 and non-PRO version of ZigBee 2007 is a good reference. Even so, you're likely to spend a few months.

Practical suggestion: stay away from wireless mesh protocol designs unless it's your job. Use ZigBee or other mature protocols with such capability. They often come free with the chip, with documentation and support.

RE: Mesh protocol!

Jörgen — Wed, 23 Oct 2013 18:16:09 GMT

It also support Gazell so some other 2.4GHz protocol would be possible.

RE: Mesh protocol!

syntroniks — Wed, 23 Oct 2013 18:05:38 GMT

Bluetooth low energy does not support any mesh networking or packet forwarding.