DTMF Relay Issue

[StewieGriffin]

 Hi,

Having the issue with DTMF relay in according the following scheme: PSTN > Voice GW (MGCP) with ISDN PRI > CUCM 8.x > CUCX 9.1
CUCX has IVR AutoAttendant with the ability (via 'Get Digit String' and 'Call Redirect' steps) of extension/dn dialing.

The issue is external (PSTN) calling party's DTMF input is in most cases doesn't get into CUCX app.
If the same app is addressed from internal phone all works like a charm and stable. So it is hardly can be UCCX side.

I've used 'debug voip ccapi inout' in the beginning of dialing extension process.
Sometimes after dialing I get the following event for voice gateway (this output is for '2' was pressed):

Jan 20 16:12:45.804 MSK: //4684/D70BB10A88FE/CCAPI/cc_api_call_digit_begin:
   Destination Interface=0x48BB1030, Destination Mask=0x1, Destination Call Id=4685,
   Source Call Id=4684, Digit=2, DigitBeginFlags=0x1,
   Rtp Timestamp=0x61388EB9, Rtp Expiration=0x0
Jan 20 16:12:45.840 MSK: //4684/D70BB10A88FE/CCAPI/cc_api_call_digit_end:
   Destination Interface=0x48BB1030, Destination Mask=0x1, Destination Call Id=4685,
   Source Call Id=4684, Digit=2, Duration=80,
   Xrule Calling Tag=0, Xrule Called Tag=0, Digit Tone Mode=DTMF
   
But most of times after pressing any digit I don't get such an event.

This makes me think about DTMF relay instability issue. Which is probably relevant of using narrowband g729 codec.
All prompts for IVR app are recorded using g729 coding.
Also it is strange that after call completion dtmf relay mode is changed to in-band. As for active call it was out-of-band.

#sh run | i dtmf|package
mgcp dtmf-relay voip codec all mode out-of-band
mgcp package-capability rtp-package
mgcp package-capability sst-package
mgcp package-capability pre-package
mgcp package-capability fm-package
no mgcp package-capability res-package

<!--- While call is active

#show call act vo id 1AEB | i mf|Rate
tx_DtmfRelay=out-of-band
TxComfortNoisePak=0
RxComfortNoisePak=0
CoderTypeRate=g729r8
CoderTypeRate=g729r8

#show call hist vo br id 1AEB

1AEB : 4703 -1961823676ms.4697 +-10 +28280 pid:0 Originate
 dur 00:00:28 tx:1342/26802 rx:1355/27100 10  (normal call clearing (16))
 IP <cucx-ip-addr>:29682 SRTP: off rtt:0ms pl:24260/20ms lost:1/1/0 delay:60/60/80ms g729r8 TextRelay: off
  media inactive detected:n media contrl rcvd:n/a timestamp:n/a
  long duration call detected:n long dur callduration :n/a timestamp:n/a

1AEB : 4702 -1961823676ms.4698 +0 +28290 pid:0 Originate
 dur 00:00:28 tx:1398/27922 rx:1355/37940 10  (normal call clearing (16))
 Telephony 0/2/0:15 (4702) [0/2/0.1] tx:28010/28010/0ms g729r8 noise:-84dBm acom:45dBm
  long duration call detected:n long dur callduration :n/a timestamp:n/a

<!--- After call is dropped from the far-end

#show call hist vo id 1AEB | i mf|Rate
tx_DtmfRelay=inband-voice
CoderTypeRate=g729r8
CoderTypeRate=g729r8

Any help will be highly appreciated.

[StewieGriffin]

 Guys,

Any suggestions? Or it'll be simplier go to g.711 codec.. =)

[Ayodeji Okanlawon]

Stewie,

There are two things you can do..

1. add dtmf package to your mgcp config

mgcp package-capability dtmf-package

2. configure mgcp dtmf to use low bit rate codcec

mgcp dtmf-relay voip codec low-bit-rate mode out-of-band

3. Once you have done the above two, reset mgcp with no mgcp/mgcp

test again and send us

debug mgcp packets

[StewieGriffin]

Ayodeji,

Ok. Before any suggested changes config from CUCM and MGCP gw were the following:

#sh run | i dtmf|package
mgcp dtmf-relay voip codec all mode out-of-band
mgcp package-capability rtp-package
mgcp package-capability sst-package
mgcp package-capability pre-package
mgcp package-capability fm-package
no mgcp package-capability res-package

+ CUCM (see the screenshot CUCM-MGCPGW-Config-PSCL).

The problem persists. Then

#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
(config)#mgcp package-capability ?
  as-package      Select the Announcement Server Package
  atm-package     Select the ATM Package
  dtmf-package    Select the DTMF Package
  fm-package      Select the FM Package
  fxr-package     Select the FXR Package
  gm-package      Select the Generic Media Package
  hs-package      Select the Handset Package
  it-package      Select the IT Package
  line-package    Select the Line Package
  mdr-package     Select the MDR Package
  mf-package      Select the MF Package
  pre-package     Select the PRE Package
  res-package     Select the RES Package
  rtp-package     Select the RTP Package
  script-package  Select the Script Package
  srtp-package    Select the SRTP Package
  sst-package     Select the SST Package
  trunk-package   Select the Trunk Package

(config)#mgcp package-capability dtmf-package ?
  <cr>

(config)#mgcp package-capability dtmf-package
(config)#
(config)#mgcp dtmf-relay voip codec low-bit-rate mode out-of-band
(config)#
(config)#no mgcp
WARNING: no mgcp: Teardown MGCP application may take a while to clean up resources
(config)#
Jan 22 15:43:27.638 MSK: %MGCP_APP-6-MGCP_SHUTDOWN_COMPLETE: MGCP Shutdown has completed
(config)#
(config)#mgcp
(config)#
(config)#end

#sh run | i dtmf|package
mgcp dtmf-relay voip codec low-bit-rate mode out-of-band
mgcp package-capability rtp-package
mgcp package-capability sst-package
mgcp package-capability pre-package
mgcp package-capability fm-package
no mgcp package-capability res-package

#wr
Building configuration...
[OK]
#

Test - the problem persists (see debug output from file 'debug.txt').
Seems every test call attempt different digits of the same extension are relayed but always incomplete.

Call history shows all my attempts were using inband-voice.

#show call hist vo | i mf        
tx_DtmfRelay=inband-voice
tx_DtmfRelay=inband-voice
tx_DtmfRelay=inband-voice
tx_DtmfRelay=inband-voice

[Ayodeji Okanlawon]

Stewie,

Sorry for the late reply..

Having looked at the logs and description there are few pointers as to what is going on here..

1. We could be looking at a dsp issue/tone generation issue

2. IOS bug that is mgcp related

To look further lets ensure that the digit are been generated by the gateway please send the ff:

debug vpm signal

debug vtsp tone

debug mgcp packet

NB: Do you hear the tones on the phone when you dial them?

[StewieGriffin]

 Ayodeji,

Yes, I hear the tones when I dial them.

It seems only 'debug mgcp packets' generates output (there is no output at all for vtsp & vpm only debug) and I've attached its corresponding data.
Actually for dialing 20055 extension we've got the following result:

1st attempt - only 20 were relayed
2nd attempt - only 05 were relayed
3rd attempt - only 205 were relayed

#debug vtsp tone
This CLI command is now 'debug voip vtsp tone'

#debug voip vtsp tone
voip vtsp tone debugging is on
#debug vpm signal
Voice Port Module signaling debugging is enabled
#debug mgcp packet
Media Gateway Control Protocol packets debugging for all endpoints is on

#sh deb              
VTSP:
  debug voip vtsp tone is ON (filter is OFF)
Voice Port Module signaling debugging is on
MGCP:
  Media Gateway Control Protocol packets debugging is on

#sh ver | i IOS    
Cisco IOS Software, 2800 Software (C2800NM-ADVIPSERVICESK9-M), Version 12.4(24)T6, RELEASE SOFTWARE (fc2)
#sh inv | i chassis
NAME: "2851 chassis", DESCR: "2851 chassis"

[Ayodeji Okanlawon]

Hi Stewie,

Lets try this..

debug vtsp dsp.

I just want to ensure that the vtsp module is sending the digits to the gateway after it has received them. So we can narrow down where the issue is.

I don't just want to jump to any conclusions. I am leaning towards upgrading the ios on the gateway but lets see I we see anything on this debug first

[StewieGriffin]

 Ayodeji,

Voice gateway always keeps silence for this debug either for successfull or unsuccessfull relays.
 
#debug vtsp dsp
This CLI command is now 'debug voip dsm dsp'
#debug voip dsm dsp
DSP Stream Manager dsp debugging is on

#sh deb
DSM:
  debug voip dsm dsp is ON (filter is OFF)

[Ayodeji Okanlawon]

Can you upgrade IOS

[StewieGriffin]

 Ayodeji, Abdel,
 
Can you recommend which IOS version to prefer? Current release:

#sh ver | i IOS    
Cisco IOS Software, 2800 Software (C2800NM-ADVIPSERVICESK9-M), Version 12.4(24)T6, RELEASE SOFTWARE (fc2)
#sh inv | i chassis
NAME: "2851 chassis", DESCR: "2851 chassis"
#sh ver | i bin         
System image file is "flash:c2800nm-advipservicesk9-mz.124-24.T6.bin"

I've also made a check against Cisco Download Software section and found the following:

12.4 - 12.4.25g(MD) [c2800nm-advipservicesk9-mz.124-25g.bin]
12.4T - 12.4.24T8(ED) [c2800nm-advipservicesk9-mz.124-24.T8.bin]

ISR's DRAM/Flash config is 256/128 and abovementioned are good with this.

Also I've changed GW's parametr 'Type Of DTMF Relay' on CUCM from 'Out of Band' to 'Current GW Config' with GW reset.
Its config didn't changed after that and stays the same. Problem also persists.

#sh run | i dtmf|package
mgcp dtmf-relay voip codec low-bit-rate mode out-of-band
mgcp package-capability rtp-package
mgcp package-capability sst-package
mgcp package-capability pre-package
mgcp package-capability fm-package
no mgcp package-capability res-package

[abdel-moniem]

Hi Stewie

My first choice would have been to go to the later 15.1 M release, but as the constrain in your DRAM/FLASH, I would believe 12.4T - 12.4.24T8(ED) [c2800nm-advipservicesk9-mz.124-24.T8.bin] could be tried first to see if the problem still persist .

Thanks

MonieM

[StewieGriffin]

 Abdel, Ayodeji,

Current time I'm running on 12.4.24T8(ED) [c2800nm-advipservicesk9-mz.124-24.T8.bin].
Unfortunately the problem still persist.

Can you, please, advice next steps in troubleshooting this issue.

[StewieGriffin]

Gentlemen,

Any ideas? Thank you.

[abdel-moniem]

Hi Stewie

I have reviewed the original traces one more time and I can see some of the digits get sent Out-of-band, but some might not be, in which it is a suspect in the firmware interpertation of the digits or DSPs. I see also the negotiation accepts the NSE in-band DTMF relay, could you inforce it int he configuration and negotiate only inband and see if this will make any difference.

You can choose NSE or NTE-GW.

mgcp dtmf-relay voip codec all mode nse

or

mgcp dtmf-relay voip codec all mode nte-gw

and collect same debugs please

[StewieGriffin]

Abdel,

Niether of the two did not resolve the issue which is the same.

debug voip vtsp tone
debug vpm signal
debug mgcp packet