Audio – Correlating multiplex RTP streams with SIP-SDP in VoIP

I try to understand more about RTP multiplexing, i. H. Where a single RTP session defined by its 5-tuple is used to send more than 1 RTP media streams. I've read that this can happen in cases like teleconferencing where there are multiple cameras and all audio / video streams are sent in one RTP session. In such cases, the SDP BUNDLE function can be used to identify the RTP streams.

My question is do / can we also multiplex RTP in VoIP, where there are several calls from several callers and callers? If so, how do we correlate the individual audio / video streams with the caller pair? Are there multiple SDP packets due to the multiple calls? What would the SDP look like in this case?