When receiving and parsing RTP audio, how do I differentiate between the various payload types that all use the same dynamic payload type in the RTP header? For example, I've got both Speex and iLBC packets coming in and both specify payload type 97 in the RTP header. How else can I tell them apart?
Payload types 96-127 fall under dynamic payload types (see RFC3551), which means that you'll need the SDP if you want more information about the media type.