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Thiago Gandara

Problem to make call from SCCP to SIP

Hi voice team,

     Outside calls arrive at extension cisco, but when the cisco extension will transfer the external call to an SIP extension, the connection is dropped.

Follow the debug, i test calling the number 4199298275 (mobile) to extension 7060 (cisco), and extension 7060 try to transfer to extension 7062 (sip), but when the person answers the call, it drops.


configure transcoder and check

But the transcorder is already configured.

Hi Thiago,

For such issues, it's always best to provide details like versions and the call flow. From what I see from the trace file, the call flow looks like this (correct me if I'm wrong):

PSTN -- H323 Gateway -- CUCM -- IP Phone 1 (SCCP)


                                   IP Phone 2 (SIP)      

I see the following in the SDI file:

09:41:57.136 |MediaManager(111412)::wait_AuConnectRequest, CI(28219037,28219042), capCount(1,0), mcNodeId(0,0), xferMode(7,16), reConnectType(0), mrid (0, 0) IFCreated(1 1) proIns(52795 25483), AC(1,0) party1DTMF(1 1 0 1 0) party2DTMF(1 2 101 0 0),reConnFlag=0, connType(3,3), IFHand(0,0),MTP(0,0),MRGL(af3fcea5-f224-2e5a-6ab5-1c9901bc5d41,af3fcea5-f224-2e5a-6ab5-1c9901bc5d41) videoCap(0 0), mmCallType(0),FS(0,0) IpAddrMode(0 0) aPid(1, 177, 73627), bPid(1, 68, 31606) EOType(0 0)|1,100,220,1.5231046^^*

The 2 Call Identifiers are the final legs which need to be joined i.e. the original H323 leg and the SIP leg. However, you can see that there is a DTMF mismatch. H323 leg can do OOB while SIP leg can do RFC2833. Hence MTP is required. UCM tries to invoke MTP:

09:41:57.136 |MediaManager(111412)::isMTPNeededForDTMF, isMTPNeeded(1)|1,100,220,1.5231046^^*

09:41:57.137 |MediaResourceManager::waiting_MrmAllocateMtpResourceReq CI=28219045, Count=2|1,100,220,1.5231046^^*

09:41:57.140 |MediaResourceCdpc(28863)::createLookupTbl Name=MTP_2 Cepn=8744afa4-c5d9-4531-a071-a01fd086f49a Weight=0 Group=0 Counter=0|1,100,220,1.5231046^^*

09:41:57.140 |MediaResourceCdpc(28863)::createLookupTbl Name=XCODER Cepn=37196750-73be-d7dc-ab80-34afddf5a41e Weight=0 Group=2 Counter=4|1,100,220,1.5231046^^*

However, both of them fail to get allocated due to device cap mismatch.

MTP_2 error:

09:41:57.140 |MediaTerminationPointControl(1)::getResourcesAllocated -- No matching caps for either side A or side B, MTP not allocated|1,100,220,1.5231046^^*

XCODER error:

09:41:57.141 |MediaTerminationPointControl(12)::waiting_AllocateMtpResourceReq - ERROR out of resource|1,100,220,1.5231046^^*

I would suggest checking and making sure that the region setting between the H323 gateway and MTP_2 as well as SIP Phone and MTP_2 is set to the same codec. In this case, it seems to be negotiating G729 codec which is possibly why the software MTP is not getting allocated. It tries XCODER but also fails. I would also doublecheck your xcode / hardware MTP to make sure it is configured properly, is registered and has enough sessions to support this call.




Hi, i do another test,i test calling the number 4199298275 (mobile) to extension 7060 (cisco), and extension 7060 transfer to extension 7062 (sip) whitout consult, and its works, but with consult don´t work.

The region is set to use G.711.

Hi Thiago,

Please refer to my analysis. It is clearly a DTMF mismatch between the 2 call legs which is resulting in UCM trying to invoke MTP. Please make sure you have tried the things suggested by me and let me know how it goes.



Ok, i will do this, then i tell you.

Hi Thiago,

                    IF possible, please provide the trace for the successful call, thanks



Follow the debug, the same numbers are used.

Hi Thiago,

Apologies for the delay, The call is failing for the same reason, i dont see the call is successful, please provide the MTP and Xcoder configuration on the gateway side. What is the codec configured for MTP ?





is it CUCM or CME?

both are registered with same CUCM if it CUCM?

both are in the same location or differrent location?

both phones are using same codec?

answer these questions please!

and configure region to use the same codec if it is different location

Its a CUCM, both are registered in the same CUCM, both are in the same location, but i dont know how codec SIP Phone use.

Hi  Thiago,

please allocate a MTP in region "RegionB=IT7 Brasilia" to the SIP phone and try

09:41:57.140 |MediaTerminationPointControl(12)::getResourcesAllocated -- Logging RegionA=IT7 Pinhais Caps and MTP/XCoder Region=IT7 Pinhais Caps|1,100,220,1.5231046^^*

09:41:57.140 |MediaTerminationPointControl(12)::getResourcesAllocated -- Logging RegionB=IT7 Brasilia Caps and MTP/XCoder Region=IT7 Pinhais Caps|1,100,220,1.5231046^^*



Hi, how can i configure this?

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