01-10-2018 09:50 AM - edited 03-17-2019 11:55 AM
I have a standard setup:
CUCM <=> CUBE <=> ITSP
In my CUBE's config, I have:
voice service voip
address-hiding
dtmf-interworking rtp-nte
mode border-element
allow-connections sip to sip
...
voice class codec 1
codec preference 1 g711alaw
...
And all my dial-peers have:
dial-peer voice XXXX voip
voice-class codec 1
dtmf-relay rtp-nte
...
I would assume that this means CUBE will force DTMF to be RFC 2833 (along with G7.11 a-law audio codec).
But if CUCM has no MTP configured on the trunk, DTMF does not work. With a call from CUCM to the ITSP, in the CUBE debugs I see:
007441: Jan 10 17:30:05.662: //177692/E42212000000/SIP/Info/info/2080/sipSPI_ipip_store_channel_info: negotiated dtmf not available, using dialpeer config dtmf = 6
And DTMF spectacularly fails to work. But G.711 a-Law works a treat.
If I set the Early Offer support on the SIP Profile for the trunk in CUCM to be "Best Effort (no MTP)" then DTMF works wonderfully.
006741: Jan 10 17:19:42.009: //177607/70333A000000/SIP/Info/info/32/sipSPIDoDTMFRelayNegotiation: RTP-NTE DTMF relay option
Simple question: Why?
If I've specified RFC 2833 DTMF everywhere in CUBE, surely it should negotiate it with all endpoints, regardless of whether they are using early or late offer media?
Thanks,
Gordon.
01-10-2018 08:51 PM
01-11-2018 06:10 AM
Does the DTMF fail to work on inbound or outbound calls? if inbound what system is it hitting that requires DTMF input? Unity, CCX, CVP, etc?
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