This new gprs-conf branch is intended to contain everything needed
to configure GPRS in the nanoBTS, but without implementing the SGSN/GGSN
functionality.
The SGSN/GGSN development will happen in a branch based on this branch
called "gprs-sgsn"
This library is intended to collect all generic/common funcitionality
of all Osmocom.org projects, including OpenBSC but also OsmocomBB
The library currently includes the following modules:
bitvec, comp128, gsm_utils, msgb, select, signal, statistics, talloc, timer,
tlv_parse, linuxlist
msgb allocation error debugging had to be temporarily disabled as it depends on
'debug.c' functionality which at the moment remains in OpenBSC
Some NM attributes are defined differently depending on
the BTS type. Having one big nm_att_tlvdef[] table for
all BTS types is no longer sufficient. This patch
* introduces 'struct gsm_bts_model' to describe a BTS model
* adds definitions of gsm_bts_model for BS-11 and nanoBTS
* changes the abis_nm_tlv_parse() function: include a bts pointer
Follow up on 424c4f0e29. As pointed out
by Sylvain on the mailinglist I need to remove this here as well.
Do not call db.c code from code that is located in libbsc.a
vty_interface.c is part of libbsc.a but it started to use code
which is found in db.c recently. Fork the subscriber dumping and
provide more information on the layer3+ (MSC) commands. This
is restoring the separation again.
This is the new logging architecture, including
* support for multiuple logging targets like stderr and vty
* log levels in addition to categories/subsystems
* filtering based on imsi, i.e. only see events for one subscriber
* dynamically change log level for each category for each vty
This has the advantage that counters can be added all over the code
very easily, while having only one routine that stores all of the
current counter values to the database. The counters are synced
every 60 seconds, providing relatively fine grained statistics
about the network usage as time passes by.
Tweaking theses can be useful especially tx-integer that influence
both the spread of rach attemps and the delay between two attemps.
Looking up GSM 04.08 3.3.1.1.2 & 10.5.2.29 can help determine good
values. The default are choosed with a wide spacing between attemps
(tx integer = 9 -> T=12 & S=217 (non-combined CCCH/SDCCH) or 115 (for
combined CCCH/SDCCH)). This alleviates the problem of responding to
several RACH attempts by a same MS, allocating several RF channels when
only 1 is needed.
Signed-off-by: Sylvain Munaut <tnt@246tNt.com>
We cannot support in-call handover of calls without a RTP proxy,
since at the time of the handover the SSRC, sequence number and
timestamp of the RTP frames change.
With ip.access, in case of TCH/H, we have one RTP stream for each half-slot
(lchan), not just one per on-air timeslot. This is quite different from
a classic BTS where the TRAU frames of the two TCH/H channels would be
part of the same 16k sub-slot in a E1 timeslot.
Before this commit, OpenBSC used templates for the SYSTEM INFO
1, 2, 3, 4, 5 and 6 messages. Those templates were patched in
various places to reflect the network config like ARFCN.
Now, we actually generate those SI messages ourselves, using
values from the configuration file, and even calculating neighbor
cell lists.
All bts'es that you have configured in OpenBSC will end up in
the neighbor cell list - which should be more than sufficient for
the current small-single-site networks.
- Make sure that on runtime the Radio Carrier can be
locked and unlocked. The vty code calls into the
Abis NM to lock/unlock the channel and the state is
stored there.
- Make sure that on start the Radio Carries remains
offline and we are not starting it. On start the
radio carrier is either locked or unlocked. This means
the RSL will not connect until the RF is unlocked. It
will connect then. To see RSL bringup failures one
needs to parse the RSL nack message.
- When the TRX is locked on startup the RSL link will
only be established after it will be unlocked.
In order to support multi-TRX configurations, we need to be able
to cope with multiple RSL streams (each with their own stream identifier)
inside one ip.access TCP connection.
Since this is very similar to using the TEI on a E1 line, we simply
recycle the logic and data fields that are used for the TEI.
We are using LAC=0 for remembering that a GSM subscriber is
detached. I recently added code to gsm_bts_by_lac that will
return every BTS in case the lac is 0. Harald highlightes
that we would now search for detached subscribers at every
BTS of our network which is clearly not what we want.
Introduce two defines for the two reserved LAC, add a
pointer to the specification, check that our config files
do not contain these reserved values, use the define
and change gsm_bts_by_lac to use the other define.
The LAC can be 16bit of size. the generation of the LAI, struct
gsm_subsriber and the BSC<->MSC was already using it as a
16bit (short) value.
Change struct gsm_bts to parse 16bit and change the vty configuration
parsing code to deal with a short too.
Transfering the cell_identity from BSC to MSC is required for the
on-waves.com support. Allow to set the cell_identity in the cfg
file and patch the system information tables to set it.
tmsi is four octets long, there is no need to make it a string
and then jump through hoops to convert it to a number. Keep the database
using it as a string to benefit from the NULL handling of the db.
Introduce the reserved tmsi which has all bits set to 1 according
to GSM 03.03 §2.4 and start checking for it and make sure the db
code will never allocate such a tmsi.
Harald Welte
Harald Welte
Sylvain Munaut