Return early in case the IMSI was already checked, if not we need
to look at the connection and check if the message could contain a
imsi we want/need to filter.
Return -1 if the IMSI should be filtered, 0 if the IMSI could not
be checked and 1 if the IMSI was checked and allowed to pass. In
the future this will be used to inspect every message coming by.
Only page if we have a load that is acceptable for paging. This
option is off by default, and can be enabled per bts. The idea
is that when we have no resources right now we will not page as
it will only create more RACHs and increase the load.
By default we are keeping the old behavior to always page and
only by changing a setting one is using the new behavior.
It might be that we run down to zero available slots but the BTS
might not send us a load indication. This can happen if we think
we send paging requests and the BTS disagrees and considers them
as errors and does not count the paging message.
When we drop to zero we will start a credit timer to give us extra
credit after six seconds, if we get a CCCH load indication before
we will stop the timer.
It is possible that the MSC is not sending the channel type it
needs for the operations it wants to do. Add a configuration option
to assign a TCH in case of paging any requests. It can be a good
idea to leave SDCCHs free for location updating requests and use
the TCH for SMS-MT and CC-MT.
Store the mapping from request to channel type in the GSM Network
struct as there is some policy involved with handling the request.
E.g. in a half rate network we don't want emergy calls to be getting
a TCH/F, or we want to have a different policy for early/late assignment
of phone calls. Update the table when creating the network and when
the neci is changed.
Allow the MS to use uplink discontinous transmission by
setting the right bit in the SystemInformation and set
DTXd/DTXu on the RSL channel commands.
This is configurable via dtx-used (0|1) on the network
level and still considered as experimental.
When the cell becomes visible we will be bombed with location
updating requests and to reduce the load on the network we should
assign as many channels for it as possible. During load peek it
is even more important than to have a spare voice channel and in
general the LU procedure is pretty fast.
Assume that if the MSC has assigned a timeslot/multiplex it will
also be used for the MGCP. So we just assume that it was allocated
on the BSC as well... in the worse case we will send a DLCX downstream
but it should be fine.
We are going to have more than one trunk, so all code hardcoding the
multiplex to zero must go. Avoid this kind of problem by saving the
MGCP endpoint number and comparing that.
Do not use the CI_UNUSED to decide if an endpoint is allocated
but introduce a new flag. This way only the CRCX and free_endp
play with the allocated field.
For debugging it is useful to forward (tee) UDP packets to another
system and use gstreamer to inspect the rtp stream. This is untested
code and might contain bugs.... and of course only tap your own calls.
Allow to switch to a dynamic port allocator and not reuse
the ports for a long time... This should help with a crazy
network sending two streams at the same time.
We plan to have two different ports for the network and for the
BTS to avoid detecting the BTS and to dynamically allocate the
port to have old data not go to a new socket.
common_vty.c was including bsc_nat.h which tried to
get the sccp/sccp_types.h which is not required to be
installed. Move all structs using/embedding SCCP structures
into the bsc_nat_sccp.h and include. This should fix
the compilation.
Currently every SAPI release indication will trigger the channel. It
was possible that we had SAPI=3 and SAPI=0 allocated and we tried to
release the channel by sending a RF Channel Release, the BTS answered
with a RF Channel Release ACK but also sent the SAPI Release Indication
which triggered a channel release here. So it was possible that we
would have released a newly allocated channel because of the SAPI
release of the old connection.
This code now works by releasing all SAPIs from highest to lowest,
then sending a SACH Deactivate and finally releasing the channel. This
approach is in use on the on-waves/bsc-master.
Add --enable-nat and --enable-osmo-bsc to build applications
requiring the Osmo SCCP library to be installed. We are not
using autodiscover as this is out of fashion.
This code compares the UDP sequence numbers of two RTP messages
and guesses if packets are missing. It is guessing in two ways:
1.) by default the sequence number is 0, so on the first
value we ignore the jump... we might ignore a real issue
in case of a wrap around which is easily possible as the
sequence should be a random number.
2.) the UDP stream might have been reordered on the network
and we would see the jump...
In any case these two shortcomings are acceptable for the feature
that is meant to provide some basic analysis..
Holger Hans Peter Freyther
Harald Welte