[OpenSIPStack] RTP Issue - opensipstack 1.1.5

[Gaurav K. <gkh...@is...>]

Hello,

 

I'm facing an issue with RTP on OpenSBC 1.1.2. My network configuration is:-

 

Xlite UA (Outbound) (.64) <--------> OpenSBC (.115) <-----------> FreeSwitch
(.57) <----------> Xlite UA (Inbound) (.57)

 

* Outbound UA is registered on OpenSBC

* Inbound UA is registered on FreeSwitch

* A route exists from OpenSBC to FreeSwitch

 

I am using:-

 

Opensipstack 1.1.5

Opensbc 1.1.2

 

I'm seeing the following errors in Level 5 log files:-

 

2007/08/07 10:46:33.745           OpalMediaThread:af4eb8           Info
RTP_UDP           Started Media Stream

2007/08/07 10:46:34.877           OpalMediaThread:aed1f8           Info
RTP       Abnormal change of sequence numbers, adjusting to expect 7614
ssrc=41

2007/08/07 10:46:35.097           OpalMediaThread:aed1f8           Info
RTP       Abnormal change of sequence numbers, adjusting to expect 7644
ssrc=41

2007/08/07 10:46:35.387           OpalMediaThread:aed1f8           Info
RTP       Abnormal change of sequence numbers, adjusting to expect 7694
ssrc=41

2007/08/07 10:46:35.698           OpalMediaThread:aed1f8           Info
RTP       Abnormal change of sequence numbers, adjusting to expect 7744
ssrc=41

2007/08/07 10:46:36.018           OpalMediaThread:aed1f8           Info
RTP       Abnormal change of sequence numbers, adjusting to expect 7793
ssrc=41

2007/08/07 10:46:36.299           OpalMediaThread:aed1f8           Info
RTP       Abnormal change of sequence numbers, adjusting to expect 7842
ssrc=41

2007/08/07 10:46:36.689           OpalMediaThread:aed1f8           Info
RTP       Abnormal change of sequence numbers, adjusting to expect 7893
ssrc=41

2007/08/07 10:46:36.980           OpalMediaThread:aed1f8           Info
RTP       Abnormal change of sequence numbers, adjusting to expect 7942
ssrc=41

2007/08/07 10:46:37.390           OpalMediaThread:aed1f8           Info
RTP       Abnormal change of sequence numbers, adjusting to expect 7992
ssrc=41

2007/08/07 10:46:37.761           OpalMediaThread:aed1f8           Info
RTP       Abnormal change of sequence numbers, adjusting to expect 8041
ssrc=41

2007/08/07 10:46:52.100           OpalMediaThread:aed1f8           Info
RTP       Abnormal change of sequence numbers, adjusting to expect 8092
ssrc=41

2007/08/07 10:46:52.400           OpalMediaThread:aed1f8           Info
RTP       Abnormal change of sequence numbers, adjusting to expect 8141
ssrc=41

2007/08/07 10:46:53.692                              Call            Info
*** DESTROYED *** SIPTimer Manager

 

The Level 5 Log & Ethereal capture on OpenSBC is attached. I'm able to hear
audio at both ends.

 

I looked up the code & found the following in rtp.cxx:-

 

      // Check for Cisco bug where sequence numbers suddenly start
incrementing

      // from a different base.

      if (++consecutiveOutOfOrderPackets > 10) {

        expectedSequenceNumber = (WORD)(sequenceNumber + 1);

                  PTRACE(1, "RTP\tAbnormal change of sequence numbers,
adjusting to expect " << expectedSequenceNumber << " ssrc=" <<
syncSourceIn);

      }

 

Is it a known issue or something which has been fixed in 1.1.7? Moreover,
when I press DTMF, I see it in Ethereal capture on OpenSBC but OpenSBC does
not seem to be detecting it. That's a different issue from the one reported
above.

 

I'll be thankful for any guidance on what's going wrong.

 

Regards,
Gaurav