OsmocomBB MNCC socket implementation without LCR

Gerard Pinto gerardfly9 at gmail.com
Mon Mar 27 09:11:29 UTC 2017


Hi Herald,

Thanks for the quick response! My apologize for the delay - I was close to
get it working so wanted to put a mail after.
GSM_TAP was the key - Thank you for this help. External CC works well now.

There was no way I could figure it out, if I hadn't enabled GSM_TAP.
It said "Invalid mandatory information"
Just  compared mncc with internal and external CC - Debugged a little
further and realized 1 of the fields of bearer_cap was missing!

mncc-python is good - I read your blog. Made some changes (socket path).
Although it does fail with "Invalid mandatory information" - bearer cap
missing. I will have to look again at the code.


*Just an off topic Question*.
Osmo-sim-auth and pysim both same projects right?
Reason I asked since, I wrote all SIM API's in osmo-sim-auth and was
planning to push upstream and then realized there is a project pysim which
has all of that ?

Thanks,
Gerard


On Fri, Mar 17, 2017 at 8:49 AM, Harald Welte <laforge at gnumonks.org> wrote:

> hi Gerard,
>
> On Fri, Mar 17, 2017 at 02:47:18AM -0700, Gerard Pinto wrote:
> > I have been working with Layer23 stack of OsmocomBB since a couple of
> > months.
> > I decided to try MNCC socket interface without LCR (I'm aware there is an
> > implementation embedded in LCR gsm-ms).
>
> Just a quick note: There's mncc-python at
> http://git.osmocom.org/mncc-python/ which you can use to interface from
> external programs/scripts, if you'd like.
>
> > Problem: I'm unable to make a call on live network, although it does
> channel
> > allocation, ciphering etc.
> > Flow:
> > 1. Create MNCC struct and write on to the osmocomBB socket
> > 2. OsmocomBB parses it well and request for channel, ciphering mode, init
> > MM, sending SETUP etc works great.
> > 3. However, in response to step.2 after sending SETUP it returns with
> (ms 1)
> > Received 'RELEASE_COMPL' in CC state INITIATED. Why does it release CC?
>
> It would be best if yo could include GSMTAP protocol traces of such
> situations, so one can analyze what happens.
>
> Also, you can compare the traces of working (no mncc?) and non-working
> (mncc) cases.
>
> Regards,
>         Harald
> --
> - Harald Welte <laforge at gnumonks.org>
> http://laforge.gnumonks.org/
> ============================================================
> ================
> "Privacy in residential applications is a desirable marketing option."
>                                                   (ETSI EN 300 175-7 Ch.
> A6)
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.osmocom.org/pipermail/baseband-devel/attachments/20170327/5d08ccd3/attachment.html>


More information about the baseband-devel mailing list