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gerrit.osmocom.org / osmo-msc / ba4d682b705c0f0793caa287e784d044f3eb12a0
commitba4d682b705c0f0793caa287e784d044f3eb12a0[log] [tgz]
authorKeith Whyte <keith@rhizomatica.org>Sun Jul 03 04:12:58 2022 +0100
committerkeith <keith@rhizomatica.org>Mon Oct 03 19:16:14 2022 +0000
tree299d5d0c6db1c2c73d577399797ef6e597c9cffb
parenteab86612d3966399f58c936b661244f1568bd139 [diff]
Change CC_CAUSE returned on unanswered MT Call

The timer "mgw X2" (RTP stream establishing timeout)
is set by default to 30 seconds.
When an MT call is ringing and remains unanswered, it
is this timer that will expire, and the call is terminated.

Up to now this results in a CC_CAUSE of Resource Unavailable
and if osmo-sip-connector is in use, the SIP agent will
get 503 Service Unavailable.
While "resource unavailable" may be technically correct, in
that the MGW did not return an rtp stream in time, returning
"No User Responding" (resulting in SIP 480) is probably a
more accurate description of what actually happened,
allowing the switch to inform the caller.

Change-Id: I4a9cfc388ec9ecb743d154a114a6db638eac4701
1 file changed
tree: 299d5d0c6db1c2c73d577399797ef6e597c9cffb
  1. contrib/
  2. debian/
  3. doc/
  4. include/
  5. m4/
  6. src/
  7. tests/
  8. .gitignore
  9. .gitreview
  10. .mailmap
  11. AUTHORS
  12. configure.ac
  13. COPYING
  14. git-version-gen
  15. Makefile.am
  16. osmoappdesc.py
  17. README.md
  18. README.vty-tests
  19. TODO-RELEASE
README.md

osmo-msc - Osmocom MSC Implementation

This repository contains a C-language implementation of a GSM Mobile Switching Centre (MSC) for 2G (GSM) and 3G (UMTS). It is part of the Osmocom Open Source Mobile Communications project.

OsmoMSC exposes

  • A over IP towards BSCs (e.g. OsmoBSC): 3GPP AoIP or SCCPlite
  • IuCS over IP towards RNCs / HNBGW (e.g. osmo-hnbgw)
  • The Osmocom typical telnet VTY and CTRL interfaces.
  • The Osmocom typical statsd exporter.

OsmoMSC implements

  • mobility management
  • call control (either via built-in MNCC handler or external osmo-sip-connector)
  • USSD (exposed via GSUP)
  • SMS (either via built-in SMSC or external via GSUP)

Homepage

You can find the OsmoMSC issue tracker and wiki online at https://osmocom.org/projects/osmomsc and https://osmocom.org/projects/osmomsc/wiki.

GIT Repository

You can clone from the official osmo-msc.git repository using

    git clone https://gitea.osmocom.org/cellular-infrastructure/osmo-msc

There is a web interface at https://gitea.osmocom.org/cellular-infrastructure/osmo-msc

Documentation

User Manuals and VTY reference manuals are [optionally] built in PDF form as part of the build process.

Pre-rendered PDF version of the current "master" can be found at User Manual as well as the VTY Reference Manual

Mailing List

Discussions related to osmo-msc are happening on the openbsc@lists.osmocom.org mailing list, please see https://lists.osmocom.org/mailman/listinfo/openbsc for subscription options and the list archive.

Please observe the Osmocom Mailing List Rules when posting.

Contributing

Our coding standards are described at https://osmocom.org/projects/cellular-infrastructure/wiki/Coding_standards

We us a gerrit based patch submission/review process for managing contributions. Please see https://osmocom.org/projects/cellular-infrastructure/wiki/Gerrit for more details

The current patch queue for osmo-msc can be seen at https://gerrit.osmocom.org/#/q/project:osmo-msc+status:open

History

OsmoMSC originated from the OsmoNITB project, which started as a minimalistic all-in-one implementation of the GSM Network. In 2017, OsmoNITB had reached maturity and diversity (including M3UA SIGTRAN and 3G support in the form of IuCS and IuPS interfaces) that naturally lead to a separation of the all-in-one approach to fully independent separate programs as in typical GSM networks.

OsmoMSC was one of the parts split off from the old openbsc.git.