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Neels Hofmeyr 986fe7ed18 store classmark in vlr_subscr, not conn
Store all Classmark information in the VLR.

So, we now always know the Classmark 1 (mandatory IE for LU). This is visible
in the msc_vlr_tests -- they no longer indicate "assuming A5/1 is supported"
because classmark 1 is missing, because we now know the Classmark 1.

Rationale:

During Location Updating, we receive Classmark 1; during CM Service Request and
Paging Response, we receive Classmark 2. So far we stored these only for the
duration of the conn, so as soon as a LU is complete, we would forget CM1.

In other words, for anything else than a LU Request, we had no Classmark 1
available at all.

During Ciphering Mode Command, we rely on Classmark 1 to determine whether A5/1
is supported. That is moot if we don't even have a Classmark 1 for any CM
Service Request or Paging Response initiated connections.

The only reason that A5/1 worked is that we assume A5/1 to work if Classmark 1
is missing. To add to the confusion, if a phone indicated that it did *not*
support A5/1 in the Classmark 1, according to spec we're supposed to not
service it at all. A code comment however says that we instead want to heed the
flag -- which so far was only present in a Location Updating initiated
connection. Now we can make this decision without assuming things.

This got my attention while hacking on sending a BSSMAP Classmark Request from
the MSC if it finds missing Classmark information, and was surprised to see it
it lacking CM1 to decide about A5/1.

Change-Id: I27081bf6e9e017923b2d02607f7ea06beddad82a
2018-09-17 01:12:13 +02:00
contrib Install systemd services with autotools 2018-09-10 16:10:06 +02:00
debian Install sample cfg file to /etc/osmocom 2018-09-12 18:49:29 +02:00
doc Install sample cfg file to /etc/osmocom 2018-09-12 18:49:29 +02:00
include store classmark in vlr_subscr, not conn 2018-09-17 01:12:13 +02:00
m4 move openbsc/* to repos root 2017-07-12 23:17:10 +00:00
src store classmark in vlr_subscr, not conn 2018-09-17 01:12:13 +02:00
tests store classmark in vlr_subscr, not conn 2018-09-17 01:12:13 +02:00
.gitignore Remove local libgsupclient; Use libosmo-gsup-client from osmo-hlr 2018-08-05 11:20:21 +02:00
.gitreview update .gitreview to new repo url 2017-08-08 17:26:28 +02:00
.mailmap add .mailmap file for mapping git author name/mail in shortlog 2016-08-08 17:40:28 +00:00
AUTHORS move openbsc/* to repos root 2017-07-12 23:17:10 +00:00
COPYING move openbsc/* to repos root 2017-07-12 23:17:10 +00:00
Makefile.am Install systemd services with autotools 2018-09-10 16:10:06 +02:00
README rewrite README 2017-09-06 16:33:41 +02:00
README.vty-tests Remove obsolete ./configure option 2017-11-29 14:24:54 +00:00
configure.ac Install systemd services with autotools 2018-09-10 16:10:06 +02:00
git-version-gen git-version-gen: Don't check for .git directory 2018-07-24 18:05:46 +02:00
osmoappdesc.py doc/examples: add detailed cs7 config examples 2017-09-07 03:10:36 +02:00

README

About OsmoMSC
=============

OsmoMSC originated from the OpenBSC project, which started as a minimalistic
all-in-one implementation of the GSM Network. In 2017, OpenBSC 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. Before, it was
the libmsc part of the old OsmoNITB. Since a true A interface and IuCS for 3G
support is available, OsmoMSC exists only as a separate standalone entity.

OsmoMSC exposes
- GSUP towards OsmoHLR (or a MAP proxy);
- A over IP towards a BSC (e.g. OsmoBSC);
- IuCS towards an RNC or HNB-GW (e.g. OsmoHNBGW) for 3G voice;
- MNCC (Mobile Network Call Control derived from GSM TS 04.07);
- SMPP 3.4 (Short Message Peer-to-Peer);
- The Osmocom typical telnet VTY and CTRL interfaces.

Find OsmoMSC issue tracker and wiki online at
https://osmocom.org/projects/osmomsc
https://osmocom.org/projects/osmomsc/wiki