Sending SMS in PDU mode fails.

[Daniele Palmas]

2017-08-07 11:04 GMT+02:00 Aleksander Morgado <aleksander at aleksander.es>:
>>>>>>> I can confirm that LE866-SV1 uses Telit custom 3GPP2 PDU format: there
>>>>>>> should be a PDU example in the AT commands user guide (see +CMGS
>>>>>>> 3GPP2), while EU variants use 3GPP.
>>>>>>
>>>>>> Thanks for the information. Then it is expected that the USA version (the
>>>>>> one I reported) does not work with ModemManager because it uses 3GPP2 PDU
>>>>>> format? Or is this format also supported in ModemManager?
>>>>>>
>>>>>
>>>>> My understanding is that it is currently not supported in ModemManager.
>>>>>
>>>>
>>>> But... https://cgit.freedesktop.org/ModemManager/ModemManager/tree/src/mm-sms-part-cdma.c
>>>>
>>>> The issue here is that the message isn't formatted as 3GPP2/CDMA
>>>> because the modem is actually an LTE modem (i.e. 3GPP). As soon as a
>>>> modem is 3GPP, we use the 3GPP format, see:
>>>> https://cgit.freedesktop.org/ModemManager/ModemManager/tree/src/mm-base-sms.c#n311
>>>>
>>>> The question now would be, is this something that happens to all
>>>> US-version Telit modems?
>>>
>>> As far as I know this happens only for Verizon customization that uses
>>> SMS over IMS with 3GPP2 pdu.
>>>
>>>> Isn't this actually a bit weird, given that
>>>> the LE866-SV1 is actually LTE-only (i.e. 3GPP-only, not 3GPP2)?
>>>
>>> Looks like a carrier requirement for SMS.
>>>
>>
>> See also Reinhard's comment about this:
>>
>> https://lists.freedesktop.org/archives/modemmanager-devel/2016-January/002468.html
>>
>
> Interesting... I now wonder how we can setup all this to work
> automatically, if at all possible. We don't have any carrier-specific
> customization right now anywhere. Maybe some user specified parameter
> asking for a specific type of PDU to generate?
>

For this specific scenario would it be a too ugly hack blindly
re-trying with 3GPP2 if 3GPP fails and then storing the setting if
successful?

Unfortunately the result code is not helpful here (CMS ERROR: 41 that
is temporary failure), but this could be something Telit specific...

Or maybe we can let each plugin take care of this: for Telit modems
probably we can think of checking some substring in the model name
(e.g. -SV or -NV). Maybe other modems have a similar rule or some
custom AT command that can be checked for that.

Just throwing some ideas, not sure how much they make sense..

However a more generic way to address carrier customization issues
could be helpful for other scenarios.

Daniele

> --
> Aleksander
> https://aleksander.es