Osmocom's Base Station Controller for 2G mobile networks
https://osmocom.org/projects/osmobsc
526b4a5f35
In case a given channel combination contains a CBCH, it replaces sub-slot 2 with a CBCH, i.e. we must not attempt to allocate the same for SDCCH. On timeslot initialization, immediately place such an lchan FSM into new state LCHAN_ST_CBCH, so that it never appears unused and never is picked during lchan_select(). Also set lchan->type = GSM_LCHAN_CBCH. Verified by configuring CBCH timeslots and watching 'show lchan summary'. Immediately after RSL and OML are up, these pchan types show lchan 2 in state CBCH: BTS 0, TRX 0, Timeslot 0 CCCH+SDCCH4+CBCH, Lchan 2, Type CBCH, State CBCH - L1 MS Power: 0 dBm RXL-FULL-dl: -110 dBm RXL-FULL-ul: -110 dBm BTS 0, TRX 0, Timeslot 1 SDCCH8+CBCH, Lchan 2, Type CBCH, State CBCH - L1 MS Power: 0 dBm RXL-FULL-dl: -110 dBm RXL-FULL-ul: -110 dBm With a 'phys_chan_config ccch+sdcch4+cbch' and three phones simultaneously requesting USSD, I see: BTS 0, TRX 0, Timeslot 0 CCCH+SDCCH4+CBCH, Lchan 0, Type SDCCH, State ESTABLISHED - L1 MS Power: 14 dBm RXL-FULL-dl: -53 dBm RXL-FULL-ul: -47 dBm BTS 0, TRX 0, Timeslot 0 CCCH+SDCCH4+CBCH, Lchan 1, Type SDCCH, State ESTABLISHED - L1 MS Power: 30 dBm RXL-FULL-dl: -47 dBm RXL-FULL-ul: -47 dBm BTS 0, TRX 0, Timeslot 0 CCCH+SDCCH4+CBCH, Lchan 2, Type CBCH, State CBCH - L1 MS Power: 0 dBm RXL-FULL-dl: -110 dBm RXL-FULL-ul: -110 dBm BTS 0, TRX 0, Timeslot 0 CCCH+SDCCH4+CBCH, Lchan 3, Type SDCCH, State ESTABLISHED - L1 MS Power: 16 dBm RXL-FULL-dl: -47 dBm RXL-FULL-ul: -47 dBm With 'phys_chan_config SDCCH8+CBCH' and three phones simultaneously attaching, I see: BTS 0, TRX 0, Timeslot 1 SDCCH8+CBCH, Lchan 0, Type SDCCH, State WAIT_RLL_RTP_ESTABLISH - L1 MS Power: 0 dBm RXL-FULL-dl: -110 dBm RXL-FULL-ul: -110 dBm BTS 0, TRX 0, Timeslot 1 SDCCH8+CBCH, Lchan 1, Type SDCCH, State WAIT_RLL_RTP_ESTABLISH - L1 MS Power: 0 dBm RXL-FULL-dl: -110 dBm RXL-FULL-ul: -110 dBm BTS 0, TRX 0, Timeslot 1 SDCCH8+CBCH, Lchan 2, Type CBCH, State CBCH - L1 MS Power: 0 dBm RXL-FULL-dl: -110 dBm RXL-FULL-ul: -110 dBm BTS 0, TRX 0, Timeslot 1 SDCCH8+CBCH, Lchan 3, Type SDCCH, State WAIT_RLL_RTP_ESTABLISH - L1 MS Power: 0 dBm RXL-FULL-dl: -110 dBm RXL-FULL-ul: -110 dBm i.e. in all cases the CBCH lchan remains occupied and is not allocated as SDCCH. Detaching and re-attaching the BTS reliably brings back the CBCH state. Also verified that changing the osmo-bsc config from telnet vty and dropping oml followed by the BTS re-attaching brings back the CBCH state. Change-Id: I2bafc5f696e818e38f8907ad0c8f38494df0623d |
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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 OsmoBSC ============= OsmoBSC 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. OsmoBSC was one of the parts split off from the old openbsc.git. Before, it worked as a standalone osmo-bsc binary as well as a combination of libbsc and libmsc, i.e. the old OsmoNITB. Since the standalone OsmoMSC with a true A interface (and IuCS for 3G support) is available, OsmoBSC exists only as a separate standalone entity. OsmoBSC exposes - A over IP towards an MSC (e.g. OsmoMSC); - Abis interfaces towards various kinds of BTS; - The Osmocom typical telnet VTY and CTRL interfaces. Find OsmoBSC issue tracker and wiki online at https://osmocom.org/projects/osmobsc https://osmocom.org/projects/osmobsc/wiki OsmoBSC-NAT is a specialized solution to navigating RTP streams through a NAT. (Todo: describe in more detail)