Harald Welte
c2007855ce
According to TS 24.007 Section 11.2.3.2.3, it is possible that uplink L3 messages are duplicated in some scenarios, particularly during assignment/handover procedure. To avoid L3 entities from seeing duplicated messages, there's a modulo-2 or modulo-4 message sequence counter, based on which the MSC can detect and suppress such duplicate messages. It appears that even our unit tests were wrong in that regard so far. Rather than manually adjusting each and every message, let's make sure that the sequence number generation always increments as expected, and that during matching of incoming messages, sequence numbers are masked out. Note: the tests will only pass from libosmocore Change-Id Iec875a77f5458322dfbef174f5abfc0e8c09d464 onwards, due to gsm48_hdr_msg_type() being broken in earlier versions. Change-Id: Id15e399ab7e1b05dcd426b292886fa19d36082b1 Closes: #2908 |
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contrib | ||
debian | ||
doc | ||
include | ||
m4 | ||
src | ||
tests | ||
.gitignore | ||
.gitreview | ||
.mailmap | ||
AUTHORS | ||
COPYING | ||
Makefile.am | ||
README | ||
README.vty-tests | ||
configure.ac | ||
git-version-gen | ||
osmoappdesc.py |
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