[cisco-voip] SIP Trunk for ISP's - DTMF SIP Notify

[Ryan Ratliff]

What phones do you have?  Most of them do in fact support RFC2833.
Additionally, using g.711 for rtp the software MTP resources on your CUCM can convert the dtmf just fine.

Even if you are using g729 you can use a software MTP on the router acting as your CUBE to do the necessary dtmf conversion which doesn't require any hardware DSPs.

-Ryan

On Jun 1, 2010, at 4:34 PM, Paul van den IJssel wrote:

> Hi Guys,
>  
> Currently I'm testing a SIP Trunk with our ISP. Everything is working fine but I don't get the DTMF to work. This because my SCCP phones only support OOB DTMF. So to get it to work with SIP RFC2833 (in-band) I need an expensive transcoder. But now we've set the SIP Trunk to SIP Notify (out-band) which should work with the IP Phones OOB, but all I get is 'SIP/2.0 403 Forbidden'.
>  
> How do I get this to work without the use of a hardware Transcoder?
>  
> Best regards,
>  
> Paul van den IJssel
> Digacom
> _______________________________________________
> cisco-voip mailing list
> cisco-voip at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-voip