Unable to dial Conf Call PIN from VOIP

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Jun 15th, 2010
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Some of our users call in to a Staples conference call; however, when they try the PIN number is not recognized.  I found that the VOIP tone is not recognized by all teleconference centers, so the dialed numbers are not being recognized.  Is there a way around this that anybody knows of?  We use Call Manager 5.1.2 and the majority of our phones are 7940 or 7960 using SCCP.  Not sure what other info you might need, but I'll be happy to give what I can.


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Jonathan Schulenberg Tue, 06/15/2010 - 14:25
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    2017 IP Telephony

What type of PSTN connectivity do you have? Analog, T1 PRI, etc.

SCCP uses out-of-band signaling so tracking this across the IP side should be easy: UCM SDI traces will confirm the existance or absence of the DTMF digits from the phone and to the PSTN gateway.

After that you will need to use gateway debugs to confirm that the digits are being sent out the circuit. This will depend on the circuit type and the protocol used to UCM. What siganling protocol are you using (H.323, MGCP, or SIP)?

To summarize: You need to isolate where in the network this is happening by doing some debug log reading.

gshamlian Thu, 06/17/2010 - 09:26
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Thanks Jonathan

I'm still quite new to VOIP and networking in general, so I hope you can forgive any poor questions or answers that I give.

The two branches that I tested use PRI, but some branches do have T1 connections.  I haven't been able to test the T1 branches yet to see if they are having the same problem.

Signaling protocol is H.323

I'll have to look up how to do a UCM SDI trace, those are new acronyms for me.  Everyday presents a new learning experience.


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