Issue with transcode and MTP con CUCM

[quytx]

Hi all

I am using UCCX and i have a problem when connect trunk to Telco. They use codec g711ulaw and g711alaw together. When call in, they send g711alaw codec and i have a problem with voice oneway. When i  enable MTP on configuration trunk on CUCM. Voice 2 way ok. But i cant call out . When i disable MTP, i can call out but will have a issue voice oneway call in for codec. The telco cant change only one codec. When call out, CUCM will send codec g711ulaw. Can you help me ?

Thanks

[quytx]

Please help me :(

[Jonathan Schulenberg]

You should not need MTP Required as CUCM should detect the mismatch between CCX CTI Port and the codec offered by the carrier to invoke the MTP automatically.

As for the inability to call out when the MTP is engaged, the only way to troubleshoot this is to look at logs. Personally, I would start at CUBE since it will let you see both “sides” of the SIP dialog and who decided to tear down the call. If you see the call never made it to CUBE or that CUCM decides to abort you would want to move your attention to the CUCM SDI/SDL traces.

[quytx]

Hi Jonathan
Thank you very much. But if i not accept MTP will voice oneway when agent pick up call. When call in i can hear the IVR but when press number to meet agent will have a issue voice one way. hmm. can u troubleshoot with me together ?.I will post log in here
Thanks

[quytx]

To day, when i change not active MTP and call not call out. hmm. i am checking with telco.This is my log from CUBE. please help me check it

IP CUCM : 10.111.182.50

IP CUBE : 10.111.182.58

IP TELCO : 125.235.28.182

Thanks

[Jonathan Schulenberg]

Did you read this log yourself and draw any conclusions or hypothesis on what is happening?

It appears the first outbound call begins on line 4339 from CUCM 10.111.182.50 to CUBE 10.111.182.58, calling number 5601, called number 0359108974, call ID a68aa980-d061fae8-4c6690-32b66f0a.
This appears to match incoming dial peer 1000 and outgoing dial peer 2011.
CUBE sends that call to the ITSP starting on line 4584 from 14.177.64.96 to 125.235.28.182, calling number 02466648888, called number 0359108974, call ID D6AE4C7F-8FDE11E9-A1BAAAED-A173211D.
The ITSP responds on line 4655 with a 100 Trying so we know they got the INVITE. This message was received at 02:31:25.892.
The next message in the ITSP-facing SIP dialog is received on line 6709 at 02:33:25.846, exactly two minutes later, as a 408 Request Timeout. CUBE relays this fatal error response back to CUCM.

Looking solely at this debug I would say your carrier owes you an explanation for where the remaining provisional responses are (e.g. 180 Ringing) as well as the 200 OK if the call actually connected. The next thing you would have owed that dialog is an ACK (assuming the missing 180 message didn't require PRACK) after receiving the 200 OK; presumably the 408 error is them giving up on that expected response from you. Since you have a working example to compare with that may offer additional clues.

[quytx]

To day, when i change not active MTP and call not call out. hmm. i am checking with telco.This is my log from CUBE. please help me check it

IP CUCM : 10.111.182.50

IP CUBE : 10.111.182.58

IP TELCO : 125.235.28.182

Thanks