OpenBSC April 2025

openbsc@lists.osmocom.org

9 participants
27 discussions

Possible Bug Issue - BAND_INDICATOR bit value is reversed
by Volkan Akkuş 27 May '25

27 May '25

Dear Sir/Ma'am, I kindly ask you to check on information below for a possible error. The claim is that the return bit value of the following function is reversed. It is supposed to be 1 instead of 0 and 0 instead of 1. https://gitea.osmocom.org/cellular-infrastructure/osmo-bsc/src/commit/2b718… Following sources are presented as proof for the claim. - Image_1 https://www.etsi.org/deliver/etsi_ts/145000_145099/145014/06.02.00_60/ts_14… - Image_2 https://www.etsi.org/deliver/etsi_ts/145000_145099/145014/06.02.00_60/ts_14… - Image_3 https://data.epo.org/publication-server/rest/v1.2/publication-dates/2016062… Thank you for your time and effort. Sorry if I have wasted your time. Volkan from Turkiye

3 4

dynamic traffic channels
by Neels Hofmeyr 20 May '25

20 May '25

On Tue, Jun 28, 2016 at 10:05:28AM +0200, Harald Welte wrote: > [translated from german] > is it certain that we switch a channel to PDCH only when > gprs mode != none? A TS can be GSM_PCHAN_TCH_F_PDCH; those are the only ones for which we send a PDCH ACT message. We send a PDCH ACT message - during init (CHANNEL OML's state changed to enabled -> send PDCH ACT), - and upon channel release ack when pchan == GSM_PCHAN_TCH_F_PDCH. So the question is, when we receive a channel release ack, could that be the PDCH release and we switch PDCH right back on by accident? No, because we only receive a chan rel ack when the *TCH/F* is being released. That is because the PDCH release is initiated "internally" from the PDCH DEACT, and thus this condition in common/rsl.c rsl_tx_rf_rel_ack() catches on, which existed before dyn PDCH: if (lchan->rel_act_kind != LCHAN_REL_ACT_RSL) { LOGP(DRSL, LOGL_NOTICE, "%s not sending REL ACK\n", gsm_lchan_name(lchan)); return 0; } In rsl_rx_rf_chan_rel() the rel_act_kind is set to LCHAN_REL_ACT_RSL, but not in the rsl_rx_dyn_pdch(). This is analogous to the ip.access way -- the ip.access nanobts replies to a PDCH DEACT with a PDCH DEACT ACK and doesn't send a separate channel release ack. Maybe we could set rel_act_kind to some new LCHAN_REL_ACT_IPAC_DYN_PDCH for clarity? (But we shouldn't actually send a release ack, to stay compatible.) Even though it works as-is, we should indeed add another flag check: - We do check the flags that no ACT/DEACT is already pending; - And we do send a PDCH DEACT only if ts->flags & TS_F_PDCH_ACTIVE; - But we would send a PDCH ACT despite ts->flags & TS_F_PDCH_ACTIVE. This should never happen, but it would make sense to ensure that. ~Neels

3 5

How to Uniquely Identify SCCP CO Sessions Over M3UA/SCTP?
by nmdbzk＠gmail.com 25 Apr '25

25 Apr '25

Hello community! I'm currently exploring the inspection of BSC/RNC<->MSC signaling traffic. At this stage, I'm focusing on dissecting SCCP connection-oriented (CO) signaling carried over SCTP (with multi-homing and multi-streaming) and M3UA. I'd appreciate any insights or suggestions. To uniquely identify individual SCCP virtual connections in a traffic dump, I'm using parameters like SLR/DLR (from CR, CC, DF1, RLSD, and RLC messages), along with lower-layer protocol details: SCTP ports, stream ID, M3UA OPC/DPC, and SLS. However, this parameter set doesn't always guarantee uniqueness—some SCCP connections appear to share the same values, leading to mix-ups, such as DTAP CC and SMS messages being interleaved. What additional indicators could I use to reliably distinguish SCCP connections? Or how do MSCs and BSCs typically differentiate and route them?

1 0

Bug Issue - BAND_INDICATOR bir value is reversed
by Volkan Akkuş 24 Apr '25

24 Apr '25

Dear Sir/Ma'am, I kindly ask you to check information below for a possible error. The claim is that the return bit value of the following function is reversed. It is supposed to be 1 instead of 0 and 0 instead of 1. https://gitea.osmocom.org/cellular-infrastructure/osmo-bsc/src/commit/2b718… Following sources are presented as proofs for the claim. - Image_1https://www.etsi.org/deliver/etsi_ts/145000_145099/145014/06.02.00_6…

1 0

LMSDevice / Bug 5338 : Power parameters requested before Tx Frequency
by jheyrendt.ext＠orange.com 24 Apr '25

24 Apr '25

Hi Sorry (perhaps it is not the right diffusion list) but We work with Osmocom with happyness and, after upgrading Debian packages AMD64, we encounter this error, and We can see that a bug has been opened. Do you know how to correct this ? in the configuration file ? or Do we have to wait for a package upgrade ? Many thanks in advance Best regards Yann 5338 OsmoTRX Bug New Normal LMSDevice.cpp:261 Power parameters requested before Tx Frequency was set! Providing band 900 by default... 03/11/2025 07:48 PM

1 0

Running hardware without internet- Setup information
by Ben Butter 09 Apr '25

09 Apr '25

Hello. So I'm trying to grasp all of these concepts. Is there a setup that doesn't require wifi to use for a cellular network after building setup? I want to use this without internet. Is that covered on any of your materials? Could you point me in the right direction? Would that be RAN?

3 3

[libosmocore] testsuite: 61 87 failed on s390x
by Jaroslav Škarvada 08 Apr '25

08 Apr '25

Hi, I built libosmocore head (commit 84dcf73625513af44e711b2c99e21ee2c33b7eff at that time) on Fedora 43 (rawhide) and on s390x 4 tests failed. Iit's s390x running in qemu on x86_64, but it also fails on native s390 - there I saw failures of tests 25 26 69 90 (unfortunately I don't have the log from the native run). So probably more tests can coredump, to see all the problematic tests, it would probably require running through the valgrind. I am reporting it according to the provided instructions thanks & regards Jaroslav

3 8

2026

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

OpenBSC April 2025