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AhmedAbdulbaky
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Your End Node is Connected To the Gateway Through a Mesh Router Node

Dears,

 

If we Have a Network of 32 Nodes ( 1 Gateway and 4 Mesh Routers and 28 End Nodes) I need To Know if It is Possible To Know that Your End Node is Connected To the Gateway through Which Mesh Router Node Programatically and When it is Self Heiling  ?, is It Possible To Know this Information ?

 

 

BR

Ahmed Abdulbaky

InnoVision Systems

 

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MaLac
Posts: 49
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Re: Your End Node is Connected To the Gateway Through a Mesh Router Node

I would like to know it as well, but I have a complementary question, I'm currently testing the system with 9 nodes, all in end mode and the gateway receive data from each one. There are no sensors connected on the node for the moment, so I don't know if the data would be good, but the "link quality" variable seem to be accurate. So is there really a 8 nodes limitation ? That would be great because it will save me the trouble of powering a node externally.

 

Matt

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Ryan_S
Posts: 91
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Re: Your End Node is Connected To the Gateway Through a Mesh Router Node

Hey AhmedAbdulbaky,

 

Unfortunately, there is no method for determining which routing method is being used by each node or whether a node is communicating through certain routers. Hope this helps!

 

--Ryan S.

Applications Engineer
National Instruments
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AhmedAbdulbaky
Posts: 17
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Re: Your End Node is Connected To the Gateway Through a Mesh Router Node

Thanks Ryan,

 

But is there any Expectation For this Feature To be Added in the Future to the WSN Nodes, as the Routing Table is Something Essentail For Using this Nodes In Our Application.

 

BR

Ahmed Abdulbaky

InnoVision Systems

Mob: (+2) 01001144651 

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Ryan_S
Posts: 91
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Re: Your End Node is Connected To the Gateway Through a Mesh Router Node

Hey MaLac,

 

Parent units (Gateways or nodes configured as routers) can only communicate with up to 8 nodes. However, the configuration of a node as a router does not impact its ability to collect or transmit information. Rather, the only difference is that its communication is always on as it interacts with the nodes and the gateway. The situation you're describing is most likely falling into one of the following two categories:

 

1. One of your nodes is configured as a router. You can check the configuration of a node in Measurement & Automation Explorer.

2. The gateway is only communicating with 8 of the nodes at one time and is, at each cycle of data collection, stranding one of the nodes.

 

Your best bet, for ensuring that a node isn't stranded, would be to make one of the nodes a router. Unfortunately, this does use more of the battery life because the communication is always active. In this case you would, as you mentioned, want to externally power this node. Hope this helps!

 

--Ryan S.

Applications Engineer
National Instruments
Member
Ryan_S
Posts: 91
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Re: Your End Node is Connected To the Gateway Through a Mesh Router Node

Hey AhmedAbdulbaky,

 

Currently, I'm unaware of any intention to include a routing table as a future feature. I would strongly encourage you to submit this as a product suggestion, as described here:

 

Product Suggestion Center

http://digital.ni.com/public.nsf/allkb/EDA7C01C684ACB6286256FF0000238D5

 

Hope this helps!

 

--Ryan S.

Applications Engineer
National Instruments
Member
MaLac
Posts: 49
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Re: Your End Node is Connected To the Gateway Through a Mesh Router Node

Hi Ryan,

None of my nodes were configured as router, that was exactly the point of my experiment, I wanted to know what happen if I connected more than 8 nodes to a gateway. To be sure that a node is not stranded, I monitored the "Last packet received" variable for each of the 9 nodes, if those timestamps matched the timestamp of the gateway for every loop, that mean that no node was stranded. It seem that sometime a node was effectively stranded, maybe 5-10% of the time. I repeated the experiment with one node as a router, and I optained the same result, 5-10% of the time a node was stranded. That make me believe that in a real case some data would be lost, even if there is no more than 8 nodes connected to the gateway or through a router.

 

Thank you

Matt

Member
Ryan_S
Posts: 91
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Re: Your End Node is Connected To the Gateway Through a Mesh Router Node

Hey Matt,

 

With regards to using more than 8 nodes per parent, this may be possible and I've seen systems where this seemed to work. However, the hardware is only tested and supported for up to 8 end nodes per parent.

 

With regard to 8 end nodes being stranded when using a router and gateway, this shouldn't be occurring. Depending on your network topology, there are other possible reasons for this behavior. The following article discusses the basics of the WSN topology:

 

Wireless Sensor Network Topologies and Mesh Networking

http://zone.ni.com/devzone/cda/tut/p/id/11211

 

When the node disconnects, is it the same node, a similar rotation of nodes, or random nodes that are being stranded? When the node becomes stranded, what's it signal strength? Are each of your nodes set for the same update rate in the project? These answers may provide clues as to what is causing this behavior. Hope this helps!

 

--Ryan S.

Applications Engineer
National Instruments