If everything works fine at HAR, we can do the bigger/better version
at 26C3,
at least if we can somehow find more than the 2-3 nanoBTS1800 that we
currently
have - at least for a couple of days.
hi harald,
i am looking forward to be at 26C3. i doubt that we can get a frequency for a test network on the 900 band, because all frequencies are assigned to GSM operators. therefore only nanoBTS1800 can be run legaly with a test license of "bundesnetzagentur". currently the application interface does not support audio streams of the nanoBTS, so other networks (ISDN/DECT/SIP) cannot be connected yet. i would like to finish audio processing for nanoBTS. can you provide me with some pcap files? a short complete call (few seconds) of one rtp session (including setup, some spoken words, and termination) would help. also the call must be made with full rate codec, so i can test the playload on the GSM codec i have. (not the enhanced full rate codec)
regards,
andreas
On Mon, Jul 27, 2009 at 10:02:42AM +0200, Andreas.Eversberg wrote:
i am looking forward to be at 26C3. i doubt that we can get a frequency for a test network on the 900 band, because all frequencies are assigned to GSM operators. therefore only nanoBTS1800 can be run legaly with a test license of "bundesnetzagentur".
There is still the option of finding a GSM900 operator to allow us to use some of their ARFCN's - but given that the 26C3 happens at Alexanderplatz in central berlin, I think they cannot do that without actually disabling some of their own TRX's in that region, i.e. without severe impact to their own network - which they will never do. Nonetheless, we can ask.
I think we might be able to use holger + dieter + my nanoBTS 1800 at 26C3, maybe something like one on each floor.
currently the application interface does not support audio streams of the nanoBTS, so other networks (ISDN/DECT/SIP) cannot be connected yet.
yes, I'm aware of that.
i would like to finish audio processing for nanoBTS. can you provide me with some pcap files? a short complete call (few seconds) of one rtp session (including setup, some spoken words, and termination) would help.
I will prepare this for you, no problem. I have the equipment with me and will probably send another mail later tonight.
also the call must be made with full rate codec, so i can test the playload on the GSM codec i have. (not the enhanced full rate codec)
of course.
One thing that comes into my mind is that the entire TRAU frame handling (and nanoBTS RTP media handling) should be moved into its own 'media gateway' process. It would be great if you feel like doing this conversion, too.
I think once the split is implemented, the MNCC interface to the media gateway process will inevitably be more general (i.e. less E1 specific). Adding MNCC/application support for the nanoBTS would probably be easy at that point.
Running OpenBSC with BS-11 and nanoBTS at the same time should also be possible at that point, since the media gateway would already be able to do input and output of both TRAU frames and RTP.
Hi Andreas,
On Mon, Jul 27, 2009 at 07:59:01PM +0200, Harald Welte wrote:
i would like to finish audio processing for nanoBTS. can you provide me with some pcap files? a short complete call (few seconds) of one rtp session (including setup, some spoken words, and termination) would help.
I will prepare this for you, no problem. I have the equipment with me and will probably send another mail later tonight.
In fact, it was much more difficult than expected. Since I only have one nanoBTS available right now, all RTP sessions usually originate and terminate on the device itelf and you never see the RTP streams.
So I've had to add RTP/RTCP proxy functionality to OpenBSC first. Now even calls between two MS on the same BTS can be routed via the RTP/RTCP proxy (by using the new "-P" option of bsc_hack).
Using this mode, I have created a pcap file with OML+RSL bringup, followed by one call between two MS (extn. 1005 calls 1003) where all RTP/RTCP packets are visible. The call uses EFR, since that is hardcoded in many places all over OpenBSC at the moment.
The pcap file is available from http://bs11-abis.gnumonks.org/trac/attachment/wiki/nanoBTS/ipaccess-startup-...
The call content is an inquiry about the subway schedule between a male and a female speaker.
Using the rtp_proxy code as a reference, it should be relatively easy to take those RTP packets and stuff them in TRAU frames (or vice versa), or passt their content upwards to an application.
Also, we still want to see the TRAU and RTP code move into a separate process. I've tried to prepare by ths, impementing all RTP related functions in gsm_04_08 rather than abis_rsl.
Regards,
hi,
On Mon, 27 Jul 2009 10:02:42 +0200 "Andreas.Eversberg" Andreas.Eversberg@versatel.de wrote:
i am looking forward to be at 26C3. i doubt that we can get a frequency for a test network on the 900 band, because all frequencies are assigned to GSM operators. therefore only nanoBTS1800 can be run legaly with a test license of "bundesnetzagentur". currently the application interface does not support audio streams of the nanoBTS, so other networks (ISDN/DECT/SIP) cannot be connected yet. i would like to finish audio processing for nanoBTS. can you provide me with some pcap files? a short complete call (few seconds) of one rtp session (including setup, some spoken words, and termination) would help. also the call must be made with full rate codec, so i can test the playload on the GSM codec i have. (not the enhanced full rate codec)
i've been talking to the bundesnetzagentur about test frequencies and temporary event frequencies for the SIGINT in cologne. i've actually made it through the whole bureaucratic process, but they had to reject us, because we applied to late (guess it takes >2 weeks, we applied 5 days before the event ;).
they didn't sound like there's no way we can get a frequency. but they told me that we are NOT allowed to connect our network to the normal telephone network (e.g. via eventphone).
so, i might talk to the bundesnetzagentur about 26c3 if you want.
cheers, codec
On Tue, Jul 28, 2009 at 08:49:46PM +0200, codec wrote:
i've been talking to the bundesnetzagentur about test frequencies and temporary event frequencies for the SIGINT in cologne. i've actually made it through the whole bureaucratic process, but they had to reject us, because we applied to late (guess it takes >2 weeks, we applied 5 days before the event ;).
Well, the question is whether or not there is any GSM900 spectrum left that they can actually assign to you. I have spoken with the respective person at the Bundesnetzagentur, and at least for Berlin he indicated that there is absolutely no such free ARFCN that they could assign to me for a test license.
Instead, he argued we should obtain permission from one of the licensees (i.e. GSM operators) and then show that permission to the Bundesnetzagentur.
they didn't sound like there's no way we can get a frequency. but they told me that we are NOT allowed to connect our network to the normal telephone network (e.g. via eventphone).
yes, that is obvious.
so, i might talk to the bundesnetzagentur about 26c3 if you want.
Sure, feel free to do it. Talking/asking never hurst. But I think GSM900 is not going to work out. Which leaves us with GSM1800, which in turn means no BS-11.
Regards,
-
Andreas.Eversberg -
codec -
Harald Welte