The VTY code makes so many allocations that a full report is
simply too long to provide any useful information. So we sub-divide
it in multiple contexts, and report only one level deep at SIGURS1.
We also introduce SIGUSR2 for the full detailed VTY report.
Change the counters_store_db function to be a generic for_each
function taking a function pointer and data. Use that in bsc_hack
to store it to the DB.
This is removing the DB requirement and will allow to handle
the counter values in different ways without making the counter
list public.
I verified that the syncing is still taking place.
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>
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.
This allows us to block packets that we have received after the channel
is no longer being used. This is visible during handover, where we still
receive a measurement report after the MS has switched to the new channel.
This leftover measurement report then attempts to trigger another handover,
which si bogus and will fail - and thus only consumes resources.
With the new LCHAN_S_ACTIVE state, we can check for this when processing
the measurement report.
This provides two functions: get_meas_rep_avg() to obtain the sliding
window average of one particular field, and meas_rep_n_out_of_m_be()
to check if at least N out of M measurments are >= BE.
During handover, we will not send RTP frames for quite some time. However,
the way the rtp_send code is structured, it will increment the timestamp
with a fixed amount every time we send a frame, independent how much wallclock
time has actually passed.
This code is a hack to update the sequence number and timestamp in case it
seems to be wrong. It makes handover much more reliable.
Instead of passing TRAU frames down the MNCC API to the call control
application like MNCC, we now decode the TRAU frame into the actual codec
frame. We do the same with the RTP packets in case of ip.access and
thus have a unified format of passing codec data from the BTS to
an application, independent of the BTS type.
This is only implemented for V1 full-rate at the moment, and needs
to be fixed.
This introduces a new LOGP() macro together with LOGL_* definition to
support multiple log levels (severities) throughout the codebase.
Please note that the actual logging system does not use them yet,
in this patch we simply introduce the new macros at the caller site.
With this commit, we can successfully hand over a channel from one cell to
another cell. We implement asynchronous intra-BSC (but inter-BTS) handover.
Changes:
* introduce new DHO log category
* extend rsl_chan_activate_lchan() with argument for HO reference
* introduce actual minimal handover decision making in handover_decision.c
* various fixes to bsc_handover_start() in handover_logic.c
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.
Since we are keeping a bitvec of the neighbor cells, we can now use
bitvec_get_nth_set_bit() to determine the ARFCN for each reported
cell in the 04.08 MEASUREMENT REPORT.
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.
* introduce a new bitvec_get_bit_pos() function to determine the bit value
at a given position inside a bit vector
* make sure bitvec_{get,set}_bit_pos() share code as possible
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.
Code to implement handover control logic. A yet-to-be-implemented
handover algorithm will call bsc_handover_start(old_lchan, new_bts)
to start the handover process.
This introduces the signals S_LCHAN_ACTIVATE_{ACK,NACK} and
S_LCAN_HANDOVER_{FAIL,COMPL,DETECT} as well as code that actually issues
those signals. The signals are relevant for a yet-to-be-written handover
control logic.
This is needed by a yet-to-be-implemented handover algorithm, after
it has allocated a new lchan for the MS. Also missing: handling
the actual HANDOVER COMPLETE / FAIL messages in response.
This patch extends struct gsm_meas_rep into a complete structure containing all
information from both uplink and downlink measurement results/reports.
This is a first step to provide this complete measurement data as a C structure
into a to-be-implemented handover decision algorithm.
- 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.
The python script is a simple call-agent driving the
client. Currently it is sending a AuditEndpoint message
and is printing the result.
The bsc_mgcp.c is a standalone process that will implement
a MGCP Gateway for the MSC. On call handling the Call-Agent
will ask the Gateway to "CreateConnection" and then this
gateway needs to communicate with OpenBSC.
Currently CreateConnection,ModifiyConnection,DeleteConnection
and Endpoint auditing is implemented.
[mgcp] Send RSIP on start and on first receive of any message
Ignore the first request and send a RSIP. We do that because
we might tunnel UDP through some other things and have no direct
way to connect to the call-agent.
Also the transaction is not checked and we ignore the response
from the call-agent, actually we print the '200 ' or any other
value as unhandled...
[mgcp] Print the MGCP command next to the response code
This allows to see which commands were sent by the server
mgcp: Terminate it with a new line
[mgcp] Make number of endpoints static...
For now this is fixed to the number of endpoints as of the GSM
specification...
[mgcp] The endpoint names seem to be base 16... use strtoul to parse
Use strtoul to parse the base 16 number from the mgw string.
[mgcp] Log the endpoints as hex numbers...
[mgcp] Only send the RSIP on the first incoming message..
Remove call_agent option (also remove the number from the getopt
call).
[mgcp] Start couting at 1 for the mgcp
[mgcp] Slight attempt to improve the grammar of the strings
[mgcp] Share validation routines between DLCX and MDCX
[mgcp] Remove help for dead config options
[mgcp] Specify a different IN addr in the SDP records
In case of NAT traversal be able to listen on a given
interface (like 127.0.0.1) but claim to receive data
at the beginning of the tunnel.
[mgcp] Fix the static copy of the SDP file
WIP verify out factoring broken..
[mgcp] Introduce VTY to the mgcp for config file parsing...
Parse the MGCP config file via the VTY framework.
[mgcp] Handle SDP parameters through VTY..
Currently the payload type, name and rate can be specified
in the config file.
[mgcp] Add an option to bind all rtp ports early
This can be useful for testing and in deployment to make sure
no runtime resource limit can be hit.
[mgcp] Add some API doc comment
[mgcp] Convert the packets of the example server to ascii
This will allow to easily patch the call id... to run the
server in a loop and make it work with the mediagateway
[mgcp] Assign CI_UNUSED... to be more obvious...
[mgcp] Use DEBUG and not DEBUGPC and specially not printf
Improve the logging a bit in the mgcp
[mgcp] Change the fake server to change the call id
This assume the call-agent will just increment the id
as well.... this is true for our implementation
[mgcp] Generate the transaction id dynamically..
This way wireshark will be more happy about it...
[mgcp] Recognize responses from the network..
This is just recognizing the response code and
then is doing nothing with it. Also change the
script to generate response messages...
[mgcp] Improve debug messages for CRCX/MDCX..
Log on which ports the media gateway is listening
and where the other (server) gateway is located
Currently this will send a dummy inactivity test message,
there is currently no parsing or API to receive the messages.
The sequencing and credit entries are empty as sequencing
is currently not used at all.
The test is currently limited to send the message and see
if the application is crashing or not.
include/sccp/sccp_types.h contain Q.713 and GSM definitions
include/sccp/sccp.h is the application interface resembling
the esentials of the UNIX socket interface.
src/sccp.c is the actual implementation of SCCP featuring
connection and UDT1 support.
tests/sccp/sccp.c is testing connection creation and formating
of the SCCP messages used by the A-interface. And
it contains a simple fuzzing test to test the
robustnes of the implementation.
Both GSM 04.08 RR and GSM 08.58 RSL need the multirate config
in the channel modify. Place the config in the lchan, change
the gsm48 methods to not take the argument, change the RSL
implementation to make use of it with the right IE.
The other code should use the t(l)v_put routines as well but
were left untouched for now.
IPA is naming these functions CRCX, MDCX, DLCX to follow
the naming of the MediaGatewayControlProtocol. Change the
code to go from BIND to CRCX (create connection) and from
CONNECT to MDCX (modify connection).
Connect indicates that it is only possible to call it once
while it is possible to call it more than once to modify
the audio parmaters and such. So the IPA terminology is
making a bit more sense here (now that we know it).
E.g. to analyze the subscr_get/subscr_put behavior one can place
the generate_backtrace into the functions, recompile and then filter
the output with contrib/bt.py to get the function name, file and line.
On channel mode modify and assignment command when using
the a multirate code the multirate configuration must be
present in the packet.
Add a parameter and add a warning when using it in a
broken way.
Allow to handle the channel requested differently based
on the NECI value for the "paging any" case. This will allow
to open a TCH/H, TCH/F depending on the neci mode.
This allows the administrator to use the vty interface to issue a silent
call to a given subscriber by using
"subscriber extension XXXX silent call start"
and stopping that silent call with
"subscriber extension XXXX silent call stop"
This is confirmed by looking at the source of their dissector.
The length can go up to 273 bytes apparently (again, according
to the source of their dissector).
Keep track of which SAPIs have been established either by the
BTS (from the MS) or by us. This can be used by the on-waves
BSC code to figure out if a new request should be made.
Be able to send RR CHANNEL MODIFY from the BSC/MSC code
as well. Move the method that knows about the IPAccess RTP
and issues the "bind" to the utils tool
Add code to generate an assignment command for a given lchan. It
is expected that the lchan is modified already and the mode will
be picked up from their. Currently only the mandantory items
are supported.
- 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)
This patch removes the need of static global variables and introduces a new,
caller-allocated 'struct ussd_request' that needs to be passed to the various
functions.
This is needed when you need to manually parse TLV blocks
that don't follow the logic supported by tlv_parse but you
still want to rely on working code and not fiddle with details.
If we have a dynamic TCH/F / PDCH channel configuration, then
we can either ACTIVATE CHANNEL it for a TCH/F, or we need to send
this vendor-specific PDCH ACTIVATE command to use it as a PDCH.
As opposed to a fixed configuration, this allows an intelligent
BSC channel allocator to use otherwise idle channels as PDCH
as long as no more TCH's are needed.
Since TS 12.21 implements only SET ATTRIBUTE for some object classes,
ip.access had to extend it to be able to set attributes on arbitrary
objects. We now introduce a function implementing that message.
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.
Tag-variableLength-Value is an encoding scheme used in the GPRS NS
and BSSGP protocols, where the length value can be 8 or 16 bits,
depending on actual demand.
Harald Welte
Sylvain Munaut
Harald Welte