TTN Downlink Problems

Configuring the gateway parameters in console.thethingsnetwork.org is not as important as it appears. Here in Australia the ‘thethings.meshed.com.au’ appears to apply arbitrary filtering on our gateways. It is the only router in this region (AU_915). so from time to time when this filtering is an issue we will swap to another router. We also don’t use thethings.meshed.com.au for applications much. because integrations are not as configurable, and we have to use a ‘special’ dashboard.

So the issue here is the “frequency plan” setting seems to only be for statistics. As is the “Router” configuration. It can be set to anything, it does not appear to mean much. When set to anything you can forward packets in anywhere. and by the Things Networks own documentation. A unregistered gateway will still work. but the packets it received will be stamped untrusted.

So back to the problem. When you use ttn.opennetworkinfrastructure.org as your router. All downlink packets are enqueued against the channel plan for EU_868. When this happens the gateways here in Australia to discards the transmission. Even though the gateways frequency plan is defined correctly in the dashboard. This lets me to believe that value is only for statistics.

60c5a8fffe74d372 >< 172.20.1.55 PUSH 207 :: {"rxpk":[{"tmst":1623936916,"chan":2,"rfch":0,"freq":917.200000,"stat":1,"modu":"LORA","datr":"SF10BW125","codr":"4/5","lsnr":8.5,"rssi":-70,"size":23,"data":"AETpAdB+1bNwEQFVAAAAAAGu+9RhEKQ="}]} :: 
thethingsnetwork <> 52.169.76.203 PULL_RESP 213 :: {"imme":false,"tmst":1622032348,"freq":869.525,"rfch":0,"powe":27,"modu":"LORA","datr":"SF12BW125","codr":"4/5","ipol":true,"size":33,"ncrc":true,"data":"IAzxv/1dO/oMXS5B/Ke4zhfnBTYMQDboBpq0FuO2fphB"}} ::

The only way to overcome this problem appears to use the correct router for the region. Which for AU_915 is the infrastructure hosted by Meshed. And I guess we will have to put up with the arbitrary filtering.

Working OTAA compatible TTN Routers

au915.thethings.meshed.com.au
router.au.thethings.network
router.us.thethings.networkMake sure the gateway has min/max TX freq set. Does work-around meshed for OTAA
Working routers for AU_915
Router DNS AddressRegionRegion
thethings.meshed.com.auAUS
router.au.thethings.networkAUS
au915.thethings.meshed.com.auAU915 915-298AUS/NZ
as923.thethings.meshed.com.auAS923 – “AS1” 922-923 AUS
https://www.thethingsnetwork.org/docs/gateways/packet-forwarder/semtech-udp.html
https://www.thethingsnetwork.org/country/australia/
Router DNS AddressRegionCountry
router.eu.thethings.networkEU433 and EU863-870EU
router.us.thethings.networkUS902-928US
router.cn.thethings.networkCN470-510 and CN779-787China
router.as.thethings.networkAS923Southeast Asia
router.as1.thethings.networkAS920-923 “AS1”Southeast Asia
router.as2.thethings.networkAS923-925 “AS2”Southeast Asia
router.kr.thethings.networkKR920-923Korea
router.jp.thethings.networkAS923-925Japan
router.au.thethings.networkAU915-928Australia
ttn.opennetworkinfrastructure.orgEU433 and EU863-870Swizerland
https://www.thethingsnetwork.org/docs/gateways/packet-forwarder/semtech-udp.html

So ensure you set your router DNS entry to one that corresponds to the table above. Otherwise the things network appears to tell the gateway to TX on an out-of-band channel. and a misconfiguration on the end of the operator could mean transmitting on licensed spectrum. and potentially prosecution. Despite every other effort being made to be compliant.

I expect the only reason why the US router works is because the downlink channels match both AU_915 and US_915

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