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RightFax dtmf with cisco IOS

Unanswered Question
Apr 25th, 2012
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I have RightFax (OpenText) server integrated as H323 gateway with cisco call manager 8.6. The problem is, if someone call from outsides and hearing the fax greeting to enter the fax number when trying to press any digit its not accepting any DTMF, i did some debugging please, check the attached file.

Please could someone check the file if its blocking the DTMF or not.

your help is appreciated.



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CHRIS HABBERJAM Tue, 05/01/2012 - 09:28
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First thing to check is that under the dial-peer make sure you have the following command:

dtmf-relay h245-alpanumeric

Then try again and see if the DTMF tones are sent to Rightfax.


marmugam Tue, 05/01/2012 - 11:50
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++ The attached debugs only voip dialpeer debugs.

++ Check with Rightfax server what is accepted dtmf method whether use rfc_2833/ or outofband.

++ h323 oob has two options, h245-alphanumeric and  h245-signal.

++ Make sure the calls is not hitting default incoming dial-peer, as it doesnt support dtmf-relay, if the call is coming from PSTN, then it should be ok.

++  What is Complete e2e call flow.

++ Currently, CUCM  suppresses 2833 negotiation when none of the call parties is SIP endpoint in the same CUCM machine if this is the case, then CCM will try to invoke a MTP. So make sure outgoing dial-peer is configured without RFC_2833. And configure same OOB dtmf methods in the Right fax server for h323. If rfc_2833 is mandatory, then you need to have appropriate MTP configured in the MRGL of h323 GW.

Here are the topologies where CUCM does not negotiate 2833
Non-SIP endpoint <------> non-SIP endpoint
Non-SIP endpoint <-------> H323 ICT trunk
Where “non-SIP” includes SCCP, H323 GW, H323 endpoint, MGCP GW.




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