VoIP
The core network of VoIP can be IMS/SIP Server/NGN
If IMS is used, SBC will process the SIP signal. If the voice call is initiated, SBC will trigger PCRF to initiate the voice dedicated bearer setup.
If SIP server/NGN is used, SBC act as SIP proxy and no Rx interface between PCRF and SBC, so the PGW should support dynamically triggering the setup of the VoIP dedicated bear by detect the packets with special UDP ports.
VoLTE
The core network of VoLTE is IMS
If the voice call is initiated, SBC will trigger PCRF to initiate the voice dedicated bearer setup
