nrf9160 NB-IoT DNS failure

RE: nrf9160 NB-IoT DNS failure

Jan Tore Guggedal — Wed, 22 May 2019 07:19:53 GMT

Hi Thomas,

I got this info from an expert on the matter: ePCO is mandatory, and should be supported by the networks, but it depends on elements that in some networks have not been updated. PCO is not directly required for NB-IoT networks, but it's been in the networks since 2009, and it's supported by all NB-IoT networks and devices.

Jan Tore

RE: nrf9160 NB-IoT DNS failure

Thomas — Wed, 22 May 2019 01:15:35 GMT

Thanks Jan, Would you happen to know if they are required to support PCO as well?

RE: nrf9160 NB-IoT DNS failure

Jan Tore Guggedal — Tue, 21 May 2019 06:26:25 GMT

Hi Thomas,

Glad to hear you were able to solve the issues. Support for ePCO is a mandatory part of the 3GPP standard for NB-IoT networks, but not all networks support the feature yet.

Could you elaborate more on this topic, Martin Lesund?

Kind regards,

Jan Tore

RE: nrf9160 NB-IoT DNS failure

Thomas — Tue, 21 May 2019 01:25:15 GMT

Thanks Jan,

It didn't work when I tried that however using the AT command XEPCO solved the issue.

Would it not be better to default to PCO if not all networks support the extended protocol? Or is the extended version not compatible, and its a case of networks supporting one or the other?

RE: nrf9160 NB-IoT DNS failure

Jan Tore Guggedal — Mon, 20 May 2019 06:48:06 GMT

Hi Thomas,

Some NB-IoT networks requires you to use PCO (Protocol Configuration Options) instead of the default ePCO in the modem. You can switch from ePCO to PCO by setting

CONFIG_LTE_LEGACY_PCO_MODE=y

in your prj.conf file.

That should hopefully help with the issues you're experiencing.

Best regards,

Jan Tore