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limiting number of DTMF signal transmitted

Hi All,

I am not sure that if it is possible or not but let me explain the situation.

The calls from PRI is forwarded to a H323  GW. IS it possible to limit the DTMF digits relayed to H323 trunk ? . For instance  for the scenario o Call – PRI – Cisco Router – H323 trunk – 3th party PBX, Is there a way to configure the PRI trunk or H323 trunk such as “ allow only 5 dtmf can be transmitted during a single call ” ? Basically the router will observe the call and the dtmfs transmitted during the call and will count it till the threshold and will not relay any more or will drop the call.

Regards ,


Everyone's tags (1)

Re: limiting number of DTMF signal transmitted

You just want to limit the number of digits passed to the 3rd party PBX?  Or are you trying to prevent users from using touch tones after they are connected to the PBX.  If it's the first, yes, there are a couple ways to do this, I think.

The first and most powerful is a translation pattern.  You can use a regular expression to add or remove digits to fir whatever your PBX requires.  However, you really need to know regular expressions, or have time to play with it, to get it to work right.

Do you know how many digits you will be receiving from the PSTN? Do you want to strip the digits from the front or rear of the number?  If it's from the front, you can use digit-strip within the dial-peer.

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