OsmoBSC is an implementation of a GSM BSC (Base Station Controller), i.e. it offers
  • an A-bis interface towards the BTSs
  • an A-over-IP (AoIP) interface towards an MSC (e.g. OsmoMSC).
  • an Media Gateway Control Protocol (MGCP) interface towards a MGW (e.g. OsmoMGW for handling the RTP user plane (voice call codec frames)

History / Naming / SCCPlite

Until 2017, we used to have an osmo-bsc part of the old openbsc.git repository which implemented a smaller sub-set of the BSC functionality with an SCCPLite based A interface. This legacy program is now called osmo-bsc-sccplite and continues to be available for legacy users. However, it is not actively developed anymore.

OsmoBSC in the Osmocom architecture

Signaling Plane only

Signaling + User (Media) Plane

BTS Support

OsmoBSC supports currently all BTSs running the OsmoBTS software (such as sysmoBTS), as well as ip.access nanoBTS devices. Other Abis/IP devices may be supported.

Support for legacy E1/T1 TDM based BTSs (like those supported by OsmoNITB is on the roadmap.

Binary Packages

Osmocom provides binary packages for several flavors of Debian and Ubuntu GNU/Linux on a variety of architectures (i586, x86_64, armhf, armv7l). Unless you are a software developer interested in developing on Osmocom, it is recommended you use those packages instead of building from source.

For more details see Binary_Packages

User Manuals

Source code

The source code is available from (module osmo-bsc).

Public read-only access is available via

git clone git://

You can browse it via cgit:

Contributions are welcome via Gerrit.

Test Suite

We have a TTCN-3 test suite as part of our Titan_TTCN3_Testsuites

Contact / Getting Help

Contact us via the openbsc@ mailing list, see Mailing Lists.

You can file issues (bugs / feature requests) using the redmine project you're currently viewing.

Authors / Credit

The old OsmoBSC-SCCPlite was created by Holger Freyther based on the earler OpenBSC/OsmoNITB code by Dieter Spaar, Harald Welte, Holger Freyther and contributors.

3GPP AoIP support was developed by sysmocom. Today, OsmoBSC is maintained by Harald Welte and his team at sysmocom.