MDL-Error in case of OsmocomBB+OpenBTS

Pavel Baturko pabftk at gmail.com
Fri Jan 11 07:33:36 UTC 2013


Hi,

Erich, I'm using OpenBTS with USRP B100 & SBX.

I encountered new problem, maybe it's similar to initial problem.
Calls and MO SMS works fine (not in 100%, but it's ok). But MT SMS
does not work (actually I received only 1 SMS from many attempts).
Mobile log (error part, from line 454):
<0001> gsm48_rr.c:429 new SAPI 3 link state idle -> established
<000e> gsm48_rr.c:5042 Radio link SAPI3 is established
<0005> gsm48_mm.c:3911 (ms 1) Received 'RR_EST_IND' from RR in state
wait for network command (sapi 3)
<0001> gsm48_rr.c:662 MON: f=50 lev=>=-47 snr= 0 ber=  0 LAI=001 01
0001 ID=0001 TA=3 pwr=19 TS=0/0
<0001> gsm48_rr.c:2864 MEAS REP: pwr=19 TA=3 meas-invalid=0
rxlev-full=-47 rxlev-sub=-47 rxqual-full=0 rxqual-sub=0 dtx 0 ba 0
no-ncell-n 0
<0001> gsm48_rr.c:4767 Indicated ta 3 (actual ta 3)
<0001> gsm48_rr.c:4769 Indicated tx_power 19
<0001> gsm48_rr.c:4767 Indicated ta 3 (actual ta 3)
<0001> gsm48_rr.c:4769 Indicated tx_power 19
<0001> gsm48_rr.c:4984 MDL-Error (cause 4) ignoring
Dropping frame with 71 bit errors
<0001> gsm48_rr.c:4767 Indicated ta 3 (actual ta 3)
<0001> gsm48_rr.c:4769 Indicated tx_power 19
<0001> gsm48_rr.c:662 MON: f=50 lev=>=-47 snr=10 ber= 42 LAI=001 01
0001 ID=0001 TA=3 pwr=19 TS=0/0
<0001> gsm48_rr.c:2864 MEAS REP: pwr=19 TA=3 meas-invalid=0
rxlev-full=-47 rxlev-sub=-47 rxqual-full=0 rxqual-sub=0 dtx 0 ba 0
no-ncell-n 0
<0001> gsm48_rr.c:3389 channel release request with cause 0x62
<0001> gsm48_rr.c:355 new state dedicated -> release pending

In trace (from packet 5509):
BTS send SABM
MS receive SABM
MS respond with UA
BTS receive UA
BTS send I frame
MS receive SABM (extra message?)
MS respond with UA
BTS receive UA
BTS send DM (disconnect request? because of extra UA respond from MS?)
BTS send Channel Release
after that MS receive I frame and send RR with ack but as I understand
this does not matter because of Chan Release..

Thanks,
Pavel

On Thu, Jan 10, 2013 at 6:02 PM, Erich Dachleger <edachleger at yahoo.com> wrote:
> What do you use to generate the network?
> The osmocombb-phone or other bts?
> cheers
> Erich
>
> ________________________________
> Fra: Pavel Baturko <pabftk at gmail.com>
> Til: baseband-devel at lists.osmocom.org
> Sendt: Mandag, 7. januar 2013 21.04
> Emne: MDL-Error in case of OsmocomBB+OpenBTS
>
> Hi list,
>
> I'm trying to connect my OsmocomBB phone to OpenBTS and I always got
> MDL-Error in mobile app log when MS trying to perform LU.
> Part of log (full mobile log in attach):
> <0001> gsm48_rr.c:355 new state connection pending -> dedicated
> <0005> gsm48_mm.c:3911 (ms 1) Received 'RR_EST_CNF' from RR in state wait
> for RR connection (location updating) (sapi 0)
> <0005> gsm48_mm.c:404 starting T3210 (loc. upd. timeout) with 20.0 seconds
> <0005> gsm48_mm.c:924 new state wait for RR connection (location updating)
> -> location updating initiated
> <0001> gsm48_rr.c:4984 MDL-Error (cause 3) ignoring
> <0001> gsm48_rr.c:4987 MDL-Error (cause 3) aborting
> <0001> gsm48_rr.c:355 new state dedicated -> idle
>
> In wireshark trace (from OpenBTS, attached) I see that MS sends LURequest
> (packet 359) and BTS responds with LUAccept (packet 440) but MS never
> receive this message because of error.
>
> As I understand this is "unsolicited UA response" from 08.58 (9.3.22) but I
> do not know how to fix that or properly debug.
> I'm using latest sylvain/testing and official OpenBTS 2.8. "Usual" (not with
> OsmocomBB) phones works with OpenBTS fine and OsmocomBB phones works fine
> with "usual" (not OpenBTS) networks.
>
> Thanks,
> Pavel
>
>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: mt_sms_fail.zip
Type: application/zip
Size: 122646 bytes
Desc: not available
URL: <http://lists.osmocom.org/pipermail/baseband-devel/attachments/20130111/77a3728e/attachment.zip>


More information about the baseband-devel mailing list