Hi,
On Tue, Sep 18, 2018 at 10:10 PM Harald Welte <laforge(a)gnumonks.org> wrote:
Hi Lorenzo,
FYI, even the (to me hyper-modern) Samsung Galaxy S5 decodes the messages
here.
I mostly work with >= 10 year old feature phones during development, as
their UI
is inside the baseband processor and closer to what happens on the GSM
protocol side
than all the smartphones that go via AT-commands or QMI.
I think the main issue is that Samsung switched baseband after the S5. I
tested just now on the S7 and it's not working.
Anyway, the
location update procedure is
successfully completed in all three phones I've tested.
that's great and confirms the related bug is fixed.
You can add iPhone7 and Galaxy S7 to the list of phones that can
successfully complete the location update procedure, with the SDCCH4+CBCH
configuration. On the other hand, on a very old Huawei LUA-L21 I'm not even
able to receive the BCCH, my cell is not present in the list. I'm not 100%
sure that's related to osmocom stack here, this phone is in a really bad
shape overall, but it works without CBCH.
I'm not sure why that is. One thing to try is to
use CBCH on SDCCH/8, and
also
to ensure that those very same phones with their firmware/software and
configuration
will show SMSCB on other/production GSM networks (in 2G-only mode!!).
I'm pretty much sure that my iPhone8, Honor 9 and Galaxy S7 can receive
broadcast notifications, because I get them during network tests for floods
and other calamities in my country. However, I never checked if they're
delivered through Paging Type 1 rest octets or through SMSCB, so this might
make a difference. And to be honest I don't remember if I was in 2G only
mode or not, but they test them once per month, so in about 2 weeks I can
check this :)
The OsmoBTS implementation of CBCH is very conservative.
* it doesn't use the optional DRX cycle
* it doesn't use the optional extended CBCH
* it definitely sends the blocks at the right time in the multiplex as per
TS 05.02,
I verified this several times
I'm going to retest all my mobile phones with the SDCCH8+CBCH configuration
and see if this makes a difference. I will let you know.
Unfortunately I don't have any pre-iPhone era phones that still work beside
my Samsung, so I cannot test anything else for a "positive" result.
Thanks!
Regards,
Lorenzo