Hello Holger,
On Mon, 19 Apr 2010 12:37:12 +0800, "Holger Freyther" <zecke(a)selfish.org> wrote:
>
> The other problem is with the 20 paging requests every two seconds I'm
> creating a RACH DoS for my BTS to a point that I think (didn't bother to
> do the easy math, and I don't have the spec here right now) we have two
> MS picking the same random number. At least the symptom is that even if
> we assign a channel, it gets closed down with a RF Failure.
I wonder how frequently it happens with 20 MS that a RACH is sent on the
same frame and with the same random number. There are at least 16 possible
random numbers for the "Answere to Paging" Channel Request and there are
27 frames in the MF to chooses from (in the "Combined Configuration").
Do you use the same phones for testing and does the RF Failure happen
frequently (this probably would mean a bad random number generator in
this phone firmware) ? Also I would expect that two RACH burst will
disturb each other, at least in a testing environment where all the
MS have the same distance to the BTS and send with the same power.
Best regards,
Dieter
--
Dieter Spaar, Germany spaar(a)mirider.augusta.de
Quoting "Andreas.Eversberg" <Andreas.Eversberg(a)versatel.de>:
hye andreas,
> output of "misdn_info"
Found 2 ports
Port 0 'mISDN_l1loop.1': TE/NT-mode PRI E1 (for phone lines & E1 devices)
30 B-channels: 1-15 17-31
B-protocols: RAW HDLC X75slp
--------
Port 1 'mISDN_l1loop.2': TE/NT-mode PRI E1 (for phone lines & E1 devices)
30 B-channels: 1-15 17-31
B-protocols: RAW HDLC X75slp
> /usr/local/lcr/interface.conf
# The MSN numbers will equal the subscriber number.
[GSM]
gsm
nt
layer1hold no
layer2hold no
tones yes
earlyb no
channel-in free
channel-out any
nodtmf
# Hint: Enter "lcr interface" for quick help on interface options.
# Add your interfaces here:
[Ext]
extern
portnum 0
[Int]
extension
msn 200,201,202,203
portnum 1
nt
> /usr/local/lcr/openbsc.cfg (or whatever your config file name is
> defined in gsm.conf)
!
! OpenBSC configuration saved from vty
!
password foo
!
line vty
no login
!
network
network country code 1
mobile network code 1
short name OpenBSC
long name OpenBSC
timer t3101 10
timer t3113 60
bts 0
type nanobts
ip.access unit_id 1801 0
band GSM1800
location_area_code 1
training_sequence_code 7
base_station_id_code 63
trx 0
arfcn 514
max_power_red 20
timeslot 0
phys_chan_config CCCH+SDCCH4
timeslot 1
phys_chan_config SDCCH8
timeslot 2
phys_chan_config TCH/F
timeslot 3
phys_chan_config TCH/F
timeslot 4
phys_chan_config TCH/F
timeslot 5
phys_chan_config TCH/F
timeslot 6
phys_chan_config TCH/H
timeslot 7
phys_chan_config TCH/H
and here is the content of the /usr/local/lcr/gsm.conf
# LCR GSM options
#################
# Enable debugging of OpenBSC library.
# Refer to OpenBSC project for debugging options.
# By default, debugging is turned off.
#debug DRLL:DCC:DMM:DRR:DRSL:DNM:DSMS:DMNCC:DMNSMS:DPAG:DMUX:DMEAS
# Two Loopback interfaces for audio transfer between OpenBSC and mISDN.
# The first interface must provide B-channelis for each call mobile call.
# The seond interface links them to LCR.
# Use 30 B-channels unless you need more due to many TRXs.
# -> Load with: "modprobe mISDN_l1loop pri=1 nchannel=30"
# By default "mISDN_l1loop.1" and "mISDN_l1loop.2" is used.
#interface-bsc mISDN_l1loop.1
#interface-lcr mISDN_l1loop.2
# Give openbsc.cnf config file
# It will be located at /usr/local/lcr by default.
config /opt/openbsc/src/openbsc.cfg
# Give database of Home Location Register (HLR)
# HLR stores all subscribers. It will be used to grant access to the network.
# It is an Sqlite3 database. Refer to OpenBSC project for handling.
# The database is located at /usr/local/lcr by default.
hlr /opt/openbsc/src/hlr.sqlite
# To keep layer 2 connection to BS11 when quitting, use this option.
# It is only usefull for developing. TRX will stay on.
# Also changes in frequency, mcc, mnc, lac while keeping layer 2 will cause
# malefunction of BSC.
# Warning: Keeping layer 2 link may prevent emergency calls. (See below)
#keep-l2
# Shutdown on emergency calls:
# This option will prevent a shutdown if an emergency call is received. In
# case of an emergency, a mobile phone may log onto you GSM network and may
# use it to set up an emergency call.
# The received emergency call will have 'emergency' as dialed number. But this
# number can't be dialed on PSTN networks without chaning.
# If you disable shutdown, be sure to provide routing of emergency calls to
# emergency facility. If you can't do that, don't touch it!
#no-emergency-shutdown
# Write BTS-Link traffic to PCAP file.
#pcapfile pcap
>
> it seems that you hook twice on some interface. are you using
> asterisk also (in conjunction with chan_lcr)?
yes i'm using it also
>
> regards,
>
> andreas
>
> p.s. please discuss this in the mailing list (see
> openbsc.gnumonks.org), so other users may have the same problems in
> the future. there are not many installations with LCR and openbsc.
>
>
>
>
> -----Ursprüngliche Nachricht-----
> Von: Fabrice Ismael Poundeu Tchouatieu
> [mailto:fabrice.poundeu@smail.inf.fh-bonn-rhein-sieg.de]
> Gesendet: Mittwoch, 21. April 2010 14:14
> An: Andreas.Eversberg
> Betreff: running lcr with openbsc and nanoBTS
>
> Quoting "Andreas.Eversberg" <Andreas.Eversberg(a)versatel.de>:
>
> hye Andreas,
>
> i'm trying to get lcr working with openbsc and nanoBTS. To be able to
> come through this i have some questions:
>
> First when i start lcr i have the following following error-informations:
>
> ** LCR Version 1.7
>
> DB: Database initialized.
> DB: Database prepared.
> ERROR Port 1 already in use by LCR. You can't use a NT port multiple times.
> LCR 1.7 started, waiting for calls...
> ERROR (in main() line 447) LCR was stalling 2.25 seconds
>
> but lcr seems to work actually. Is that the normal way it works or it
> there something wrong? I have nothing else running on LCR.
>
> When i then try to set a call, lcr break out with the following information:
>
> layer3_thread read socket error No space left on device
>
> I don't known how many space is needed therefore, or in which folder
> or directory this space should be available. But the drive is quite
> empty. there is so much space available on it!
>
> Also can you send me an example of a working dialplan and sip.conf to
> enable the routing of gsm calls??
>
> thanks and best regards!!
>
> --
> Fabrice Ismael Poundeu Tchouatieu
>
> ----------------------------------------------------------------
> This message was sent using IMP, the Internet Messaging Program.
>
>
>
--
Fabrice Ismael Poundeu Tchouatieu
----------------------------------------------------------------
This message was sent using IMP, the Internet Messaging Program.
Hi!
I've been offered a 'developer room' at FrOSCon 2010 (http://www.froscon.de/)
which will be at FH Bonn-Rhein-Sieg (http://www.fh-brs.de/) in Sankt Augustin
from August 21/22 this year.
Before sending a response, I would like to inquire whom of you would actually
have any intention of visiting this conference and spending time in the
developer room to work on OpenBSC or OsmocomBB ?
I think the idea is great to meet some of you guys [again], not only at the
annual CCC congress in winter. But there is little point for me to go there if
there is no interest from the wider project community.
Please provide your feedback ASAP.
--
- Harald Welte <laforge(a)gnumonks.org> http://laforge.gnumonks.org/
============================================================================
"Privacy in residential applications is a desirable marketing option."
(ETSI EN 300 175-7 Ch. A6)
Hello Holger,
On Tue, 20 Apr 2010 10:42:34 +0800, "Holger Freyther" <zecke(a)selfish.org> wrote:
>
> What happens is that the IMMEDIATE ASSIGNMENT does not make it to the
> phone fast enough and the same MS is sending another RA and we assign
> another channel.
>
> The root causes consist of various issues:
> - Our delay in src/input/ipaccess.c does not help, removing it
> is breaking the rugby sized BTS though..
> - Our paging layer sends the paging command in bursts... we
> should have an even distribution of them.
> - We have some NM attributes to play with.
>
> I am going to poke this some more.
I sometimes had the same problem in the past even with a single MS. If
you want to play with the parameters which control sending the RACH
burst, you can try the configuration commands "rach tx integer" for
the number of slots used to spread retransmission or "rach max
transmission" for the number of retransmitted burst. Of course in
a perfect world OpenBSC should work with all possible configurations.
Best regards,
Dieter
--
Dieter Spaar, Germany spaar(a)mirider.augusta.de
Hi all,
I will implement the following changes on the on-waves/bsc-master branch
and if no one is screaming move them over to master shortly afterwards.
Right now I'm experiencing the following problem. When enabling the RF
on the BTS hordes of MS come to the network for Location Updating
Requests and the SDCCHs are close to 100% loaded, now I want to send a
SMS to every new Subscriber welcoming it (ideally one would do it during
the LU but... well... it does not). To deliver the SMS we need to page
the SMS and currently we are paging 20 MSs during 2 seconds.
The first problem is that the nanoBTS can not handle this load for a
long time, it is sending CPU Overload and as of GSM 08.58 we should
handle it by throttling the transfer but well that is not implemented.
The other problem is with the 20 paging requests every two seconds I'm
creating a RACH DoS for my BTS to a point that I think (didn't bother to
do the easy math, and I don't have the spec here right now) we have two
MS picking the same random number. At least the symptom is that even if
we assign a channel, it gets closed down with a RF Failure.
So here is my problem:
- Remove the notion of paging slots... the nanoBTS is not
even sending the load indication anyway.
- Look at free channels (ignoring the requested channel at
first... something we need to fix later) and have a config
switch like.. only page if the cell is like 50% loaded or
such. I will figure out the details while doing the changes.
The other reason to write this mail is, I think it is pretty interesting
to see how our experiments from the congress look different to what I
was seeing due way more paging going on.
regards
holger
Hi!
I've been working on a set of patches to enable configuring the nanoBTS
to not only support GPRS but also EDGE. After some testing, I've merged
them into the master branch.
In order to enable EDGE, you need to use 'gprs mode egprs'.
Also, you still need an external SGSN or use the gprs-sgsn branch (which has
been rebased). Your phones should then show 'E' instead of 'G'.
I haven't actually benchmarked the transfer speed, i.e. if it really is giving
the expected performance improvement.
Regards,
Harald
--
- Harald Welte <laforge(a)gnumonks.org> http://laforge.gnumonks.org/
============================================================================
"Privacy in residential applications is a desirable marketing option."
(ETSI EN 300 175-7 Ch. A6)
Hi guys
I have been looking through the SMS functionality of openBSC and I can see that the HLR / SMS database uses an sender_id (a secondary key of the Subscriber database). Is it possible to send SMS messages with an alpha originator i.e. from a string of text up to 11 characters?
I also noticed that using the telnet interface, the command to send a SMS does not leave a trace in the sql database.
Thanks, Stuart
Hello
I am interested in buying a BS-11 or nanoBTS for testing..
I tried contacting ip.access but they demand a spectrum license...:(
Does anybody have some for sale?
Sent from my iPhone