relay node in mesh

RE: relay node in mesh

arpita — Wed, 08 May 2019 09:39:52 GMT

i have taken 2 servers with same group address. server1 is in range to client, server2 is out of range.

now i want to control server2 which is out of range to the client. how to do this.

RE: relay node in mesh

awneil — Wed, 08 May 2019 09:30:11 GMT

[quote userid="78547" url="~/f/nordic-q-a/46810/relay-node-in-mesh/185879"]i am trying same as saral is doing[/quote]

Perhaps some background reading will help - especially in understanding the terminology:

https://devzone.nordicsemi.com/f/nordic-q-a/45818/about-mesh-network/180515#180515

RE: relay node in mesh

tesc — Wed, 08 May 2019 09:21:23 GMT

Hi,

You bind the same application key to client and server. Then you either:

configure the client to publish to the server unicast address, or
configure the client to publish to a group address and configure the server to subscribe to that same group address.

After that, whenever the client publishes a message that message should propagate through the network and reach the server.

All you need to do is the configuration in the "ends" (client and server.) How the message is relayed is automatically handled by the network. Both clients and servers can act as relay nodes. The relay feature is not related to mesh models.

Regards,
Terje

RE: relay node in mesh

arpita — Wed, 08 May 2019 09:13:38 GMT

even i am trying same as saral is doing. i have the same question what is publication and source address to give if i want to relay from one server to another with "nrf mesh mobile app".

RE: relay node in mesh

tesc — Tue, 07 May 2019 16:09:27 GMT

Hi,

Have you tested this with the light switch example, in particular followed the section Testing the example thoroughly?

First get the example up and running, and confirm that you get communication through multiple hops with the configuration set up by the static provisioner. (Or, with the configuration described in the "Evaluating using the nRF Mesh mobile app" if instead you use the nRF Mesh app for the provisioning.)

When that one is working properly you can have a look at how to configure the nodes differently in order to suit your particular scenario of one button (node A) controlling two lights (node B and node C).

Regards,
Terje

RE: relay node in mesh

ps_anu — Sat, 04 May 2019 05:27:09 GMT

yes i have tried. but i am not getting message to node c . Tell me how to do this in nRF mesh app or using provisioner . please guide me

Thanks in advance

RE: relay node in mesh

tesc — Fri, 03 May 2019 13:30:38 GMT

Hi,

[quote user="saral"]i want to transmit the data for a long distance so that my destination node will be not dependent on source node.[/quote]

And that is exactly what Bluetooth mesh does, without any configuration. The message will take multiple hops until it has spread through the whole network. (Up until a configurable maximum number of hops known as the Time To Live (TTL), ranging from one to 127 hops.)

Regards,
Terje

RE: relay node in mesh

awneil — Fri, 03 May 2019 10:15:20 GMT

[quote userid="74848" url="~/f/nordic-q-a/46810/relay-node-in-mesh/185085"]this is the algorithm i want to do[/quote]

So you are trying to develop your own Mesh protocol, then?

Because what you describe is not how BLE Mesh works!

Perhaps you should investigate (some of) the other Mesh Network standards (eg, Zigbee, Thread) before re-inventing this wheel?

https://www.google.com/search?q=comparison+of+sensor+mesh+networks

[quote userid="8164" url="~/f/nordic-q-a/46810/relay-node-in-mesh/185101"]What is the motivation for wanting to control the forwarding of messages? What do you get from that, what is your end goal[/quote]

Indeed!

http://www.catb.org/esr/faqs/smart-questions.html#goal

RE: relay node in mesh

ps_anu — Fri, 03 May 2019 09:39:05 GMT

By this ,i can achieve longer distance node . i want to transmit the data for a long distance so that my destination node will be not dependent on source node.

RE: relay node in mesh

tesc — Fri, 03 May 2019 09:09:46 GMT

Hi,

If you want to send one message to two nodes, then you can use a group address. Configure the client to publish to the group address. Configure the two servers to subscribe to the group address.

In Bluetooth mesh you don't have control of the specifics regarding where messages travel, as awneil has explained very well already. What is the motivation for wanting to control the forwarding of messages? What do you get from that, what is your end goal?

Regards,
Terje

RE: relay node in mesh

ps_anu — Fri, 03 May 2019 08:27:36 GMT

please have a look below , this is the algorithm i want to do

Each node acts as both a transmitter and a receiver.
Each node wants to forward every message to every one of its neighbors except the source node.
want to forward the message from one node to the nearest node which is in range

how to do this ?

RE: relay node in mesh

awneil — Fri, 03 May 2019 08:13:50 GMT

[quote userid="74848" url="~/f/nordic-q-a/46810/relay-node-in-mesh/185019"]Then how can we do managed flooding ?[/quote]

You don't!

The mesh stack manages that for you. That is what the mesh does.

Just like you don't specify the path that your IP packets take from your computer to the Nordic website and back - that is all handled by the Internet. That is what the Internet does.

And just like you don't specify the path that a phone call takes when you call someone on your phone - the phone network takes care of that. That is what the phone network does.

RE: relay node in mesh

ps_anu — Fri, 03 May 2019 01:28:18 GMT

As per you said :

You don't control the routing within the mesh

Then how can we do managed flooding ? In our case C is not in the range of A . B is in range of A. We should achieve like A ----- B-------C

RE: relay node in mesh

awneil — Thu, 02 May 2019 18:08:49 GMT

[quote userid="74848" url="~/f/nordic-q-a/46810/relay-node-in-mesh/184985"]Do you understand my question[/quote]

No: your question doesn't really make sense - as tesc says, you don't control the routing within the mesh

RE: relay node in mesh

ps_anu — Thu, 02 May 2019 17:07:08 GMT

Thank you for your response tesc. Do you understand my question. Actually I want to send the message from A (client ) ----B (server 1which acts as relay node) ------C ( server 2). I want to do hopping from one node to another and so on and should reach the destination .how to do publish /subscribe ?

I know only Unicast address of each device .. which address I should give for subscribe. Can you clearly explain me

Thanks in advance

RE: relay node in mesh

tesc — Thu, 02 May 2019 15:37:14 GMT

Hi,

In Bluetooth mesh you never think about what route a particular message will take through the network. All you need to do for messages to reach their destination is to provision all the nodes into the network. Then everything will work as long as the network is contiguous (and as long as the path that a message must take is shorter than the configured time to live.)

For configuration, node A should publish to the address of node C or to a group address that node C subscribes to. It should also use an application key. If you used a group address, then node C must subscribe to that group address. Node C must also use the same application key.

Regards,
Terje