Codecs report

[Yankovskyi]

Hi all.

There are cluster CUCM 7.1.3. and three AS 5350.(SIP)

In our cluster is one default Region with g711 codec. All inbound and outbound calls pass excellent.

But it is a problem with recorder server (ZOOM). There are 1-2 calls per day which are not recorded and have status "Different codecs in each stream".

We can see this status in ZOOM recorder server.

I have checked all settings on CUCM and AS, everywhere is g711 ulaw codec.

But ZOOM support insist on settings wutj codecs in CUCM.

I can't catch this problem call, because it's very a a little amount of this calls and I don't know when this call will be.

My question is next:

how  can I see what codecs was used in calls? In the past calls?

I can't find it in CDR and RTMT.

Thanks!!!

[Chris Deren · Accepted solution]

Region configuration in CUCM does not imply specific codec, but rather a maximum codec that can be negotiated, so if you have region with G711 to other region or within itself and a call comes from device that attempts to negotiate at G729 for example, since G729 is lower rate it will be allowed.  Review your configuration on the GW to ensure you do not have any dial-peers configured with G729 or no codec applied or codec class as the default IOS codec is G729.

HTH, please rate all useful posts!

Chris

[Yankovskyi]

Thanks  for explanation,

I have checked configuration on the GW. There was voice-class codec with three codec: G711ulaw G711alaw and G729.

I have left only G711 ulaw. Now I will observe.

Chris could you explain more about codecs:  Is there possible that call has different codecs for each stream?? I can't imagine how.

Can we see what codecs was in past calls in CDR??

Thank

[Chris Deren]

When you say different codecs for each stream, I am assuming you are not talking about one call but different calls, if so it is possible if the calls come from different sources or route to different destinations if G729 is allowed along the path and negotiated, however the voice-class codec prioritizes the codecs. As of CUCM 9.0 you can build similar prioritization via "codec preference":

http://www.cisco.com/en/US/docs/voice_ip_comm/cucm/rel_notes/9_0_1/delta/CUCM_BK_N38FD301_00_new-and-changed-information_chapter_01.html#CUCM_RF_C0735CE6_00

As to CDR it should show negotiated/used codec for each call.

HTH,

Chris

[Yankovskyi]

sorry, I am saing about different codecs in one calls, is it possible?

There is such error for not recorded call in ZOOM. I can attach screenshot if you want.

When I didn't see this error, I had thought that a call can negotiate only one codec type for two stream.

[Chris Deren]

No, you will not see each side of the conversation with different codec. I would contact the ZOOM application developer and have them explain it to you.

Chris

[Yankovskyi]

I have attached screenshot with problems records, you can see this problem status

Thank you very much!!!

I will ask ZOOM developer.

[will.alvord]

This looks like what you're running into:

https://supportforums.cisco.com/thread/2031749

I believe you said that you're using g711 ulaw everywhere, but what about on the trunk to the call recording server?

Edit: I meant to point out that apparently the error message about the codec mismatch on the different streams means that the phone negotiated a different codec on the call recording server stream than the actual call endpoints did.

[Yankovskyi]

Thanks for link.

There is very similar situation, but it is one distinction. We use SPANless recording server. IP Phones don't use BIB function. They don't send any RTP to recording server. They don't know anything about recording server.

CUCM Publisher sends jtapi information to ZOOM. ZOOM gets RTP from SPAN port.