IMS: Function difference between MRFC and MRFP components of Media Resource Function ?

Question

Is it mandatory to establish a separate default bearer to exchange IMS signaling messages between UE and IMS network nodes ? Can't internet default bearer be used for the same ?

Answer 1

MRF is made of two components named as MRFC (Media Resource Function Controller) and MRFP (Media Resource Function Processor). MRFC is mainly responsible to manage available MRFP resources, it provides abstraction to AS from the MRFP resources.
MRFP interprets and process the commands sent by the AS. Manage the media stream and perform the media processing.