Hi everyone!
I have a BTS that is trying to connect to openbsc via SCTP, but as i see it is not supported. I have attached a capture file between the core network equipment and BTS
10.0.0.7 is the IP Address of the ABIS link and port is 14597 the rest is for UMTS and LTE so please ignore it. I would be really gratefull if someone could look into this Kind thanks to everyone!
On Mon, Sep 02, 2019 at 11:55:35PM +0200, Borjan Jovanovski wrote:
Hi everyone!
I have a BTS that is trying to connect to openbsc via SCTP, but as i see it is not supported.
Interesting, SCTP on the Abis link is new for me.
openbsc (or osmo-nitb) has long been deprecated. The new programs to use are described here: https://osmocom.org/projects/cellular-infrastructure/wiki/Osmocom_Network_In...
All of our currently supported 2G BTS models connect to OsmoBSC via TCP/IP (Abis).
SCTP is supported for the A interface (between BSC and MSC), and for Iuh serving 3G cells, but not for 2G BTS to connect to the BSC.
And just to make sure we're not confusing things: since your filename is 'hnb.zip' and your pcap contains Iub Signalling, it looks to me like you are trying to connect a 3G cell? We have SCTP support for attaching hNodeB to the osmo-hnbgw -- this is not Abis, but the Iuh interface. There is no "OsmoRNC" program yet (and probably won't be any time soon), so the only way to run 3G with Osmocom CNI is to use an hNodeB femto cell that already includes the RNC and talks Iuh to osmo-hnbgw (or operate your own RNC that talks IuCS to osmo-msc and IuPS to osmo-sgsn, which has never been tested before).
I hope this clarifies things?
~N
Dear Mr. Hofmeyr,
Thank you for your kind help and support, yes it is also new to me, it is mostly used in comercial systems due to the network size and complexity, but yes i can confirm that i am talking about ABIS over SCTP. I even have some documentation about it. The device in question is a multimode (GSM,UMTS,LTE) Macrocell so the packet capture contains the following information:
10.0.0.5 LTE SCTP port 36412 10.0.0.7 ABIS over SCTP for GSM port 14597 10.0.0.8 RNC IuB SCTP Port 29169
As of now also, another question, is there an open source RNC available?
Thanks once again for the help and support!
On Tue, Sep 03, 2019 at 01:47:16AM +0200, Borjan Jovanovski wrote:
10.0.0.7 ABIS over SCTP for GSM port 14597
Hmm, wireshark shows only "DATA" there, doesn't offer decoding as any GSM protocol. Briefly skimming the raw bytes, they don't really look like Abis OML nor RSL to me.
I guess you would have to implement support from scratch using the documentation you mentioned.
As of now also, another question, is there an open source RNC available?
At least not that we know of. If you find one, shout!
~N
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Borjan Jovanovski -
Neels Hofmeyr