Does 3CX IPPBX support 180 ringing with SDP?

[Grace Liu]

After we register one sip account(Non 3CX certification) into 3CX IPPBX, the 3CX web client calls out to my mobile through sip account, when my mobile starts to ring, the web client does not hear any ringback tone. But when we call out to another one mobile number(we do not change any settings), if another one mobile starts to ring, the web client can hear the ringback tone.

So we make the captures in 3CX IPPBX when we call out, and we make a comparison between two outbound calls. We find that when 3CX IPPBX receives the 180 ringing with SDP, the web client will not hear any ringback tone:

When 3CX IPPBX receives the 180 ringing without SDP, the web client will hear the ringback tone.

Can we know whether 3CX IPPBX supports 180ringing with SDP?

Thanks
Regards
Grace

 

[YiannisH_3CX]

Hi @Grace Liu

3CX does support 180 ringing with SDP. However if we receive a 180 Ringing with SDP we then expect audio to be sent from the provider. If the provider is not sending the ringing audio after the 180 Ringing with SDP then the caller will not hear any ringback.
From the screenshot is not clear if the provider is sending audio to the PBX but I do not see any RTP going to the PBX.

 

[Grace Liu]

Hello @YiannisH_3CX

Thanks for your explanation, and I get it.
We will check it with the sip provider.

Thanks
Regards
Grace