In many cases we actually want a name / unique ID for the lchan,
not just for the on-air timeslot... especially in SDCCH/8 case,
where 8 SDCCHs share one timeslot...
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>
This implements the handover algorithm (and associated parameters)
as described in Chapter 8 of the book "Performance Enhancements in
a Frequency |Hopping GSM Network" by Thomas Toftegard Nielsen and Jeroen
Wigard.
The parameters such as averaging windows are configured in struct
gsm_network. We keep some state to trakc up to 10 neighbors as
they are being reported from the MS.
This has so far only been tested in a network with two BTS that
have each other as neighbor. Networks with morge neighbors might
encounter bugs.
We will need this for the actual handover algorithm implementation, as we will
only know the current BTS and the BCCH ARFCN of the strongest cell in the
measurement reports. Using this new function, we can resolve the matching
gsm_bts.
We use a 1024-bit-sized bitvec to generate the BA and neighbor frequency list.
This bitvec is still generated from the list of all BTS's inside the BSC, but
this patch is the first step to generalize this, i.e. generate arbitrary
neighbor lists.
- 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.
- Improved handling of extension-number string (as per review)
- Guard against a buffer-overflow if mobile sends a too-long USSD
- declare some function-parameters const
- fix gsm_ts_name function to display the right BTS number (bts->nr rather than bts->bts_nr)
Supporting GPRS means we have a number of additional OML objects to
deal with. We need to extend our gsm_bts structure to at least
include the nm_state for each of those objects.
Add support for 1900 nanoBTS by using unified bts_type
GSM_BTS_TYPE_NANOBTS for 900, 1800 and 1900 versions.
Reduce the nanoBTS enum values to one and derive the
version from the user supplied band. In the future we
might want to do auto band detection.
The configuration file needs to be changed to refer
to nanobts instead of nanobts900/nanobts1800.
Signed-off-by: Mike Haben <michael.haben@btinternet.com>
Signed-off-by: Holger Hans Peter Freyther <zecke@selfish.org>
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.
For the on-waves.com MSC case we want to page every BTS reached
of the network. Our gsm_subscriber entry does not have a LAC
entry set and defaults to zero. Use the reserved 0x0000 to
indicate that we want to use every bts in the network.
This will influence the paging code to start and stop paging.
* add bts->band field plus corresponding VTY and commandline argument
* add trx->nominal_power and trx->max_power_red fields
* add rsl_chan_bs_power_ctrl() to control TRX RF power for a given TS
* add rsl_chan_ms_power_ctrl() to control MS RF power for a given lchan.
This is Harald's reworked MNCC base, slowly heading towards integration
into master. The key changes are:
* provide much more structure to the data in gsm_mncc
* encode_* and decode_* functions now take a structure rather than tons
of individual arguments (whose order nobody can remember)
* make sure we don't have copies of the same code everywhere by introducing
mncc_set_cause() and mncc_release_ind()
* save horizontal screen space if possible
* make sure we break lines > 80 characters
Harald Welte (local)
Harald Welte
Sylvain Munaut