SLM 2.4.0 + RAI

[Ofir_A]

Hi, 

We want to use RAI with SLM FW and not sure how to add it
I've read some tickets regarding it but still no walkthrough.

Here are the steps we do now:

1. Receive GPS fix

2. Connect to out server

3. Send data and GPS

4. Check shadow

5. Close connection

6. Send Sleep=2 command

After the sleep command there is a time when the modem is still active and consuming power, and when the network is release the current drops to what it should be (happen the same with PSM or EDRX)

We want to know how to add the RAI (in code or AT commands) that immediate after Sleep=2 the modem will go idle 

Any guide regarding this issue?

We connect with MQTT (LTE-M)

[Øyvind]

Hello! 

I've read some tickets regarding it but still no walkthrough.

No, there is no good walk-through, there is this blog post on DevZone  Maximizing battery lifetime in cellular IoT: An analysis of eDRX, PSM, and AS-RAI .

We want to know how to add the RAI (in code or AT commands) that immediate after Sleep=2 the modem will go idle 

There are two possible ways to enable RAI:

1. %XRAI = "CP-RAI" (only for NB-IoT, but not a really useful feature in practice)
2. %RAI = "AS-RAI" (Release 14 feature, saves a lot of power consumption by skipping the rrc inactivity timer)

When we are talking about RAI we are referring to the release 14 feature (enabled by %RAI)

You should be able to use AT command Release assistance indication %RAI to enable RAI on your device. And you can test this with a simple sample that my colleague Charlie made here.

Let me know how that works for you. 

Kind regards,
Øyvind

[Ofir_A]

Øyvind said:

When we are talking about RAI we are referring to the release 14 feature (enabled by %RAI)

You should be able to use AT command Release assistance indication %RAI to enable RAI on your device

I've already tried this with no effect

we don't know how and where to add the socket so I can inform it is the last message.

We do send sleep=2 when we finished so I want it to send the RAI too.

Øyvind said:

And you can test this with a simple sample that my colleague Charlie made here.

It is not relevant, we use TCP

[Øyvind]

Ofir_A said:

It is not relevant, we use TCP

The test would possibly confirm that you are able to enable RAI on your device i.e. that the network does allow RAI. 

Ofir_A said:

I've already tried this with no effect

Please provide a modem trace for our modem team to look at. 

Thank you. 

Kind regards,
Øyvind

[Ofir_A]

Øyvind said:

Please provide a modem trace for our modem team to look at. 

It's a little problematic with our product to get modem trace
will check something with the SW engineer and let you know on sunday

[Øyvind]

Yes, that is true. Hope that you are able to get one in an easy manner. You could also the sample that I suggested with the nRF9160DK, this should at least provide information on the network when using the same SIM card.

-Øyvind

[Achim Kraus]

> we don't know how and where to add the socket so I can inform it is the last message.

If you use the "serial_lte_modem" that app maintains the socket for you.

With "AT#XSOCKETOPT" (see the documentation there) you should the be able to "set SO_RAI_LAST" or "set SO_RAI_NO_DATA".

> We do send sleep=2 when we finished so I want it to send the RAI too.

Enter "sleep=2" is not related to RAI and so that doesn't set the socket opt for you.

[Achim Kraus]

> It's a little problematic with our product to get modem trace

> Yes, that is true.

Our customers do not need to know which RAI is supported

I guess, this is simply an wrong assumption by Nordic. Not only here or in the referenced topic, the question is frequently, if AS-RAI or CP-RAI is supported by the network.

Instead of asking for traces, wouldn't it be ways easier to report that to the user's application?

[Øyvind]

Achim Kraus yes, you have been discussing this topic for a while and we understand that you are not happy in how we handle certain aspects of our features and documents. In this case I'm not asking for which is supported but rather if RAI is supported in the network. For the case of our users we hope that our documentation is relevant and updated for their use-case, and we constantly providing feedback to our R&D department for improvements and bug fixes.

[Achim Kraus]

> In this case I'm not asking for which is supported but rather if RAI is supported in the network.

There is no big difference to report "AS-RAI:" => "supported" / "not supported" by the network, or "AS-RAI", CP-RAI" and "No-RAI" supported by the network. But the later will help all.

And for now, nothing is reported, because someone decided "customers do not need to". But the customers here in the forum seems to need it ;-).