Sending data from EndDevice1 to Gateway to EndDevice2 without backhaul

End Devices (Nodes)
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Hello… Newbie question… We are considering LoRa and LoRaWAN for a multi sensor project with 5 to 30 end devices. I understand that end device to end device connections are not supported. My question is can data be sent from one end device to another using a COTS gateway alone or must data go through a gateway AND an application server?

Here’s our situation… About 90% of the data on the network will be sent from remotely powered End Device 1 to other battery/solar powered End Devices. The remaining 10% will be End Devices sending data through the gateway to the application server via cellular backhaul. If the 90% of data must also go through the cellular backhaul the cost of cellular data and possibly latency become a factor.

As mentioned earlier we’d like to use a COTS gateway, however if the above description is not reasonable, we may be able to develop a custom gateway using a device like the SX1302 with our ED1 but naturally that complicates the project which we’d like to avoid.

Thanks.

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In theory you could re-write elements of the gateway packet forwarder software or some models of gateways you can run a network & application server.

But anything like that is off topic for this forum I’m afraid, we are all about LoRaWAN through TTN.

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LoRaWAN is designed for device to application communication, not for device to device. While it is possible to implement logic on the gateway to facilitate this it would still not be a great fit for LoRaWAN.

Keep in mind LoRa devices burn a considerable amount of energy while in receive mode, in the order of ten-twenty milliamperes which is usually not a great fit for battery/solar operation. To reduce energy consumption LoRaWAN nodes usually only listen for a few moments after a transmission, this allows operating multiple years with a battery, but only if you’re not transmitting often (transmission consumption is up to 150mA)
All in all not a great match for device (via gateway) to device communication.

For custom solutions based on Lora you might want to ping @cslorabox.

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descartes… I follow you. Thanks for the reply.

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Kersing… Thanks for the response and I will reach out to @cslorabox. I think we would be ok in regards to managing power as on wakeup, the node sends out message that it is awake which in effect is a request for data from the controller which is co-located with a customized gateway. The controller replies with the data. Then the end node makes a measurement and sends that to TTN.
I won’t keep pushing this here as I seem to be off topic for this forum and don’t want to wear out my welcome.

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