20 Apr
2020
20 Apr
'20
6:02 p.m.
Hi all,
I am new to the use of the Osmocom project, it is indeed a very nice job.
I am currently trying to set up a configuration with a Asterisk PBX server and I have 2
questions:
1/ RTP configuration
The SIP part (sip-connector vs Asterisk connection) works well so far, the communication
starts but with no audio.
I noticed that the RTP flux is sent to localhost instead of my server address (set as
remote in sip-connector.cfg) and I was wondering if there is any possibility to send the
RTP flow to an address which is not localhost ?
sip
local 0.0.0.0 5069
remote 127.0.0.1 5060
2/ codec issue
In a configuration where all the Osmocom servers (MSC, MGW, BSC…) and Asterisk are on the
same machine, it got a message from my asterisk server, saying that no codec can be found
to start a communication. By default, the wiki/manuals states that gsm has to be used but
perhaps I am missing something in the BSC configuration, especially in the codec choice.
<--- SIP read from UDP:10.184.10.162:5069 --->
INVITE sip:899@127.0.0.1:5060 SIP/2.0
Via: SIP/2.0/UDP 10.184.10.162:5069;rport;branch=z9hG4bKpe1UXZU1amUja
Max-Forwards: 70
From: <sip:422@0.0.0.0:5069>;tag=vyQKX32r72ZyQ
To: <sip:899@127.0.0.1:5060>
Call-ID: cd65c5a0-fdbf-1238-51a9-000c29cfd753
CSeq: 949096397 INVITE
Contact: <sip:10.184.10.162:5069>
User-Agent: sofia-sip/1.12.11devel
Allow: INVITE, ACK, BYE, CANCEL, OPTIONS, PRACK, MESSAGE, SUBSCRIBE, NOTIFY, REFER,
UPDATE
Supported: timer, 100rel
Content-Type: application/sdp
Content-Length: 133
v=0
o=Osmocom 0 0 IN IP4 127.0.0.1
s=GSM Call
c=IN IP4 127.0.0.1
t=0 0
m=audio 4016 RTP/AVP 3
a=rtpmap:3 GSM/8000
a=sendrecv
<------------->
--- (13 headers 8 lines) ---
Sending to 10.184.10.162:5069 (no NAT)
Sending to 10.184.10.162:5069 (no NAT)
Using INVITE request as basis request - cd65c5a0-fdbf-1238-51a9-000c29cfd753
No matching peer for '422' from '10.184.10.162:5069'
== Using SIP RTP CoS mark 5
Got SDP version 0 and unique parts [Osmocom 0 IN IP4 127.0.0.1]
Found RTP audio format 3
Found audio description format GSM for ID 3
[2020-04-20 17:38:19] NOTICE[14918][C-00000015]: chan_sip.c:10957 process_sdp: No
compatible codecs, not accepting this offer!
Thanks for your help
Laurent