Media Gateway Control Function (MGCF) provides the following functions:
Media Gateway (MGW) provides the following functions:
Transport Signaling Gateway (TSG) provides the following functions:
Multimedia Resource Function (MRF) provides the following functions:
The S-CSCF, possibly in conjunction with an application server, shall determine that the session should be forwarded to the PSTN. The S-CSCF will forward the Invite information flow to the Breakout Gateway control function (BGCF) in the same network. The BGCF selects the network in which the interworking should occur based on local policy. If the BGCF determines that the interworking should occur in the same network, then the BGCF selects the MGCF which will perform the interworking, otherwise the BGCF forward the invite information flow to the BGCF in the selected network. The MGCF will perform the interworking to the PSTN and control the MGW for the media conversions.